Association between Grit at the Start of Residency and Depressive Symptoms at the End of Residency Among Postgraduate Year 1 Medical Residents in Japan: A Longitudinal Study

Association between Grit at the Start of Residency and Depressive Symptoms at the End of Residency Among Postgraduate Year 1 Medical Residents in Japan: A Longitudinal Study | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Research Article Association between Grit at the Start of Residency and Depressive Symptoms at the End of Residency Among Postgraduate Year 1 Medical Residents in Japan: A Longitudinal Study Toshinori Nishizawa, Nobutoshi Nawa, Yu Akaishi, Eriko Okada, and 3 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-6631869/v1 This work is licensed under a CC BY 4.0 License Status: Published Journal Publication published 19 Jul, 2025 Read the published version in BMC Medical Education → Version 1 posted 10 You are reading this latest preprint version Abstract Background Grit, defined as perseverance and passion for long-term goals, played an essential role in academic success and resilience in the medical profession. Previous cross-sectional studies indicated an association between higher grit and lower depressive symptoms among medical residents. However, no longitudinal studies examined whether grit was associated with later depressive symptoms during residency training. This study explored the association between grit at the start of a job and depressive symptoms at the end of the first-year postgraduate (PGY1) residency among Japanese medical residents. Methods This longitudinal study analyzed data from all first-year postgraduate residents at Tokyo Medical and Dental University in Tokyo, Japan, from 2021 to 2023. We administered surveys at the start of the first-year postgraduate residency and again at the end. We measured grit using the Japanese version of the Short Grit Scale (Grit-S) and assessed depressive symptoms with the Center for Epidemiologic Studies Depression Scale. We examined the association between grit at the baseline and depressive symptoms at the end of the first-year postgraduate residency using Poisson regression with robust error variance analysis. Results Of the 146 residents, 28 (19.2%) exhibited depressive symptoms at the end of first-year postgraduate residency. After adjusting for baseline depressive state, age, sex, graduated university, sleeping hours, and training program, a one-unit increase in Grit-S score was associated with a 42% lower risk of depressive symptoms at the end of the first-year postgraduate residency (relative risk [RR]: 0.58; 95% confidence interval [CI]: 0.37–0.88). Furthermore, the Grit-S subscales, perseverance of effort and consistency of interest, were all associated with a lower risk of depressive symptoms (RR: 0.68; 95% CI: 0.48–0.96, RR: 0.70; 95% CI: 0.49–0.99, respectively). Conclusion This study demonstrated that higher grit at the start of residency was significantly associated with a lower risk of depressive symptoms among Japanese medical residents by the end of their first postgraduate year. Grit depressive symptoms depression medical resident longitudinal study Figures Figure 1 Introduction The medical profession is inherently stressful, with a high prevalence of depression, burnout, and other mental health issues [ 1 , 2 ]. Resident physicians, in particular, are at an elevated risk of developing depressive symptoms due to their recent transition from medical student to resident physicians, and lack of communication skills, medical knowledge, and experience [ 3 ]. In a large cross-sectional survey in Japan, 22.6% of first-year postgraduate (PGY1) residents had new depressive symptoms after 3 months of training [ 4 ]. Residents having depressive symptoms tend to make more medical errors than those without​​ [ 3 , 5 , 6 ]. Thus, it is crucial to identify residents at risk of depression to provide preventive and timely support. Grit is the passion and perseverance for long-term goals, as coined and defined by Angela Duckworth [ 7 ]. Grit has garnered significant attention in the medical literature for its positive association with academic achievement, career success, and psychological well-being, as well as its negative association with depression, burnout, and residency attrition [ 8 ]. In Japan, our previous cross-sectional study has shown that PGY1 residents with high grit scores have lower depressive symptoms compared to those with lower scores at the beginning of a job [ 9 ]. Our other cross-sectional study also reported that the Grit total score and two subscales, such as perseverance of effort and consistency of interest scores, were inversely associated with depressive symptoms in medical students [ 10 ]. The cross-sectional study from the USA showed that among surgical residents, high grit was inversely associated with depression as well as positively predictive of psychological well-being [ 11 ]. Although several studies have demonstrated the association between Grit and depression among resident physicians [ 9 , 11 ], there is a lack of longitudinal studies. Cross-sectional studies provide valuable insights, but in a cross-sectional design, there is the potential for reverse causality, with individuals with higher depressive symptoms responding lower on grit score. Longitudinal studies will allow researchers to examine whether grit at the start of residency is associated with lower levels of depression later, after adjusting for depressive symptoms present at the beginning of residency. This can inform the development of targeted interventions to support residents' well-being. This study aims to fill the gap in the literature by conducting a longitudinal study that examine the association between grit at the start of residency and depressive symptoms at the end of the PGY1 residency among first-year medical residents in Japan. Methods Study Participants We conducted this longitudinal cohort study at Tokyo Medical and Dental University (TMDU) in Tokyo, Japan. The study initially recruited all PGY1 residents (N = 284) who joined the TMDU resident program in 2021, 2022, and 2023​​. We performed the baseline online survey approximately at the start of the PGY1 residency in April. We conducted the follow-up survey at the end of the PGY1 residency in March. The online survey, administered in Japanese, included items assessing Grit using the Japanese version of the Short Grit Scale (Grit-S) [ 12 ], depressive symptoms using the Japanese version of the Center for Epidemiologic Studies Depression Scale (CES-D) [ 13 ], and other covariates, all adapted from a prior cross-sectional study [ 9 ]. Japanese residency programs provide a comprehensive 2-year training experience that requires all residents to rotate through major specialties at approved hospitals throughout Japan. The TMDU residency program is divided into mainly two distinct types. Program 1 provides PGY1 training in TMDU Hospital, an academic medical center and tertiary emergency medical facility, and PGY2 training in a community-based hospital. Program 2 provides PGY1 training in a community-based hospital and PGY2 training in TMDU Hospital. This program has been a standard practice since 2004​​ [ 14 ]. We conducted this study in accordance with the Declaration of Helsinki, which was approved by the Institutional Review Board of Tokyo Medical and Dental University (IRB approval number M2019-283). We obtained informed consent from all participants before participation in the study​​. We excluded residents who did not consent or failed to complete all of the surveys. Therefore, residents who participated in this study have no missing values in this study. Grit At the start of the PGY1 residency, we measured grit among PGY1 residents using the Japanese version of the Grit-S, which was verified for factor structure, reliability, and validity among 1043 Japanese university students [ 12 ]. Grit-S was designed as a modified version of the original Grit Scale [ 15 ] and consisted of eight items using a five-point Likert scale ranging from 1 to 5 [ 16 ]. Final scores were added up for each question and divided by the number of questions, ranging from 1 (not at all gritty) to 5 (extremely gritty). The scores of the two subscales, namely the perseverance of effort and consistency of interest, consist of four items with similar score ranges of the total grit score. Grit-S was validated for internal consistency, test–retest stability, and predictive validity of this scale [ 16 ]. Cronbach’s alpha of our study was 0.75, 075, and 0.65 for Grit-S, perseverance of effort, and consistency of interest scores, respectively. The continuous Grit-S, perseverance of effort, and consistency of interest scores were used for the analysis. The Grit-S was measured at the baseline survey ​. Depressive Symptoms We measured depressive symptoms using the Japanese version of the CES-D [ 13 ], which was validated using the original CES-D, a widely recognized scale for assessing depressive symptoms over the past week [ 17 ]. We defined a score of ≥ 16 on the CES-D as indicative of depressive symptoms [ 18 ] and utilized the scale as a categorical variable in the analysis​​​​. In a validation study of the Japanese version of the CES-D, a cut-off score of 16 demonstrated a sensitivity of 88.2% and a specificity of 84.8% [ 13 ]. We collected the CES-D by administering online surveys at two time points (at the start and the end of the PGY1 residency). Covariates We collected several covariates from the basic data at the start of the PGY1 residency, including demographic variables such as age, sex, start year of training, type of training program, and name of graduated university. We obtained the type of residency program to see if the PGY1 training environment is different TMDU hospital from community-based hospital. The name of the graduated university was identified to assess familiarity with the training environment, as residents who graduated from TMDU are more familiar due to their clinical clerkship at TMDU hospital. In addition, lifestyle factors were collected from the online baseline survey at the start of the PGY1 residency, including average sleeping hours on weekdays, smoking habits (categorized as never, past smoker, or current smoker), drinking habits (categorized as never, only a few times a month, or more than a few times a week), frequency of eating breakfast (categorized as every day, more than several times a week, or less than a few times a week), and frequency of exercise within the last month (categorized as almost never, less than a few times a week, or more than several times a week). Statistical Analysis We calculated descriptive statistics for all variables to compare differences between groups. We used Poisson regression with robust error variance to evaluate the association between baseline grit scores and the presence of depressive symptoms at the end of PGY1. In addition, we also evaluated the association between the Grit-S subscales, perseverance of effort and consistency of interest, and the presence of depressive symptoms at the end of PGY1. We adjusted for potential confounders, including baseline depressive state, age, sex, university attended, average weekday sleeping hours, ​​and type of residency program [ 9 , 19 ]. We presented the results as relative risk (RR) with 95% confidence interval (CI), and statistical significance was set at a p-value of < 0.05. We conducted all analyses using Stata version 17.0 (Stata Corp LLC, College Station, TX, USA)​​. Results As shown in Fig. 1 , between April 2021 and March 2024, 284 PGY1 residents joined the TMDU resident program. Residents who disagreed to participate in the study (N = 2), who had no response at the baseline survey (N = 50) and at the follow-up survey (N = 73), and who had missing value at the baseline survey (N = 9) and at the follow-up survey (N = 4) were excluded from the study. As a result, 146 residents were included in the analysis. As shown in Table 1 , among 146 residents, 28 (19.2%) residents were categorized as depressed group at the end of the PGY1 residency. The Grit-S score at the baseline was significantly lower in the depressed group (mean: 2.96 ± 0.55) compared to the non-depressed group (mean: 3.31 ± 0.59). Regarding Grit-S subscales, the perseverance of effort score of the depressed group was significantly lower than that of the non-depressed group (3.25 ± 0.68 vs. 3.58 ± 0.69). The consistency of interest score was significantly lower in the depressed group (mean: 2.66 ± 0.62) compared to the non-depressed group (mean: 3.03 ± 0.75). Additionally, a higher percentage of residents in the depressed group were identified as depressed at baseline (50.0%) compared to the non-depressed group (14.4%). Table 1 Characteristics of study participants. Depressed N = 28 (19.2) Non-Depressed N = 118 (80.8) p-value Age (years), mean (SD) 25.2 (1.33) 24.9 (1.92) 0.440 Sex, n (%) Male 18 (64.3) 67 (56.8) 0.469 Female 10 (35.7) 51 (43.2) Start year of training, n (%) 0.809 2021 9 (32.1) 40 (33.9) 2022 7 (25.0) 23 (19.5) 2023 12 (42.9) 55 (46.6) Graduated university, n (%) 0.936 TMDU 14 (50.0) 58 (49.2) Others 14 (50.0) 60 (50.8) Type of residency program 0.371 Program 1 11 (39.3) 36 (30.5) Program 2 17 (60.7) 82 (69.5) Marriage, n (%) 0 (0) 5 (4.2) 0.583 Presence of family living together, n (%) 1 (3.6) 20 (17.0) 0.078 Weekday sleeping hours, mean (SD) 7.26 (1.22) 7.32 (0.90) 0.764 Smoking habits, n (%) 0.051 Never 27 (96.4) 109 (92.4) Past smoker 0 (0) 9 (7.6) Current smoker 1 (3.6) 0 (0) Drinking habits, n (%) 0.066 Never 6 (21.4) 16 (13.6) Only a few times a month 18 (64.3) 60 (50.9) More than a few times a week 4 (14.3) 42 (35.6) Frequency of eating breakfast, n (%) 0.454 Every day 21 (75.0) 78 (66.1) More than several times a week 2 (7.1) 21 (17.8) Less than a few times a week 5 (17.9) 19 (16.1) Frequency of exercise within the last month, n (%) 0.143 More than several times a week 3 (10.7) 33 (28.0) Less than a few times a week 11 (39.3) 33 (28.0) Almost never 14 (50.0) 52 (44.0) Grit-S, mean (SD) 2.96 (0.55) 3.31 (0.59) 0.005 Perseverance of Effort, mean (SD) 3.25 (0.68) 3.58 (0.69) 0.023 Consistency of Interest, mean (SD) 2.66 (0.62) 3.03 (0.75) 0.016 Depressed at baseline, n (%) 14 (50.0) 17 (14.4) < 0.001 Bold indicates p < 0.05. As shown in Table 2 , the crude analysis revealed an association between a one-unit increase in the Grit-S score at baseline and a 53% reduction in the risk of having depressive symptoms at the end of PGY1 (RR: 0.47; 95% CI: 0.29–0.74). After further adjusting for depressive symptoms at baseline, age, sex, graduated university, weekday sleeping hours, and type of residency program [ 9 , 19 ], a one-unit increase in the Grit-S score was associated with a 42% reduction in the risk of having depressive symptoms (RR: 0.58; 95% CI: 0.37–0.88). Table 2 Adjusted relative risk ratio for association between depressed state at the end of PGY1 and Grit-S score. Crude Adjusted Relative risk 95%CI Relative risk 95%CI Grit-S 0.47 0.29–0.74 0.58 0.37–0.88 Adjusted for depressed state at baseline, age, sex, graduated university, weekday sleeping hours, and type of residency program. Bold indicates p < 0.05. As shown in Table 3 , the crude analysis indicated that a one-unit increase in the perseverance of effort score was associated with a 39% reduction in the risk of having depressive symptoms at the end of PGY1 (RR: 0.61; 95% CI: 0.41–0.89). Similarly, the crude analysis showed that a one-unit increase in the consistency of interest score was significantly associated with a 43% reduction in risk (RR: 0.57; 95% CI: 0.39–0.83). Furthermore, after further adjusting for depressive symptoms at baseline, age, sex, graduated university, weekday sleeping hours, and type of residency program [ 9 , 19 ], the perseverance of effort score was significantly associated with a lower risk of having depressive symptoms (RR: 0.68; 95% CI: 0.48–0.96), as well as the consistency of interest score (RR: 0.70; 95% CI: 0.49–0.99). Table 3 Adjusted relative risk ratio for association between depressed state at the end of PGY1 and Grit-S subscale scores. Crude Adjusted Relative risk 95%CI Relative risk 95%CI Perseverance of effort 0.61 0.41–0.89 0.68 0.48–0.96 Consistency of interest 0.57 0.39–0.83 0.70 0.49–0.99 Adjusted for depressed state at baseline, age, sex, graduated university, weekday sleeping hours, and type of residency program. Bold indicates p < 0.05. Discussion In this longitudinal study, we found that higher baseline grit scores among PGY1 residents were significantly associated with a reduced risk of developing depressive symptoms by the end of their PGY1 residency. This association remained significant even after adjusting for baseline depressive symptoms and other covariates such as age, sex, university attended, average weekday sleeping hours, and type of residency program. Our findings were consistent with the previous cross-sectional studies suggesting a protective effect of grit against depressive symptoms in Japan and the USA [ 9 , 11 ]. Our previous cross-sectional study indicated that after adjusting for age, sex, graduated university, and weekday sleeping hours, Japanese PGY1 residents with higher grit scores reported lower levels of depression at the time of the job start (adjusted odds ratio, 0.37; 95% CI, 0.19–0.74) [ 9 ]. The cross-sectional study from the USA also showed that among surgical residents, grit was significantly inversely predictive of depression (coefficient (b) for the total grit score = − 0.28, p < 0.01) after adjusting for age, gender, ethnicity, and marital status [ 11 ]. Moreover, the longitudinal study from the USA indicated that grit at baseline was significantly associated with lower rates of burnout six months later than those with less grit after adjusting for gender and baseline burnout among surgical residents (b = − 0.20, p = 0.01) [ 20 ]. However, no longitudinal studies examined whether grit was associated with later depressive symptoms during residency training after adjusting for baseline depression. Because there is the potential for reverse causality in a cross-sectional design, our longitudinal study adds to the literature by demonstrating that higher grit serves as a predictor of one-year-later depressive symptoms in a clinical training setting. The following pathways may explain how high grit serves as a protective factor against depressive symptoms. First, occupational stress mediates the relationship between grit and depression [ 21 ]. Individuals with high levels of grit can recover from negative emotions to positive emotions faster [ 22 ], have lower psychological exhaustion [ 20 ], and use a negative event as an opportunity for growth more [ 21 ]. Also, individuals with high levels of grit may know how to cope in a stressful environment and have increased psychological security [ 23 ]. This can reduces interpersonal stress, thereby resulting in less risk for depression [ 23 ]. Second, presence of meaning in life may mediate the association between grit and depression [ 24 ]. Individuals with high levels of grit are more likely to realize that life is meaningful and to stay motivated in looking for the meaning of their lives, and are therefore less likely to experience maladaptive emotional states. Third, mindfulness may mediate the association between grit and subject well-being [ 25 , 26 ]. Individuals with high levels of grit have higher levels of mindfulness, which might have been protective against depressive symptoms. Future research should examine whether occupational stress, presence of meaning in life, and mindfulness mediates the association between grit and depressive symptoms among medical residents, which we were not able to evaluate in this study. Finally, we found that two subscales of grit were inversely associated with depressive symptoms. These results were consistent with cross-sectional study that showed Grit-S subscales, perseverance of effort and consistency of interest, were significantly associated with lower depressive symptoms among Japanese medical students after adjusting for sex, age, and survey year [ 10 ]. Our study adds to the literature by demonstrating the association using longitudinal design. While perseverance of effort may be associated with academic engagement, subjective well-being [ 27 ], and authentic pride [ 28 ], consistency of interest may be associated with reduced psychological distress [ 29 , 30 ]. These results underscore the importance of fostering both subscales of grit to reduce the risk of developing depressive symptoms. Our study has important strengths. This is the first longitudinal study to evaluate the impact of grit on one-year later depressive symptoms after adjusting for baseline depressive states and other covariates. However, there are several limitations to consider. First, the study was conducted at a single institution, which may limit the generalizability of our results to other residency programs. Second, self-reported measures of grit and depressive symptoms could introduce response biases, such as social desirability bias, impacting the validity of the data collected. Third, the type of the residency program was adjusted, but this study could not assess the training details. Finally, we utilized a self-administered questionnaire and identified residents who had a CES-D score of 16 or higher, categorized as positive for depressive symptoms. It is important to note that this does not mean a formal diagnosis of depression. Implications In this study, we demonstrated that low grit scores at the start of a job were significantly associated with depressive symptoms at the end of the PGY1 residency. Residency program directors should evaluate grit scores for resident physicians at the start of employment and closely follow residents with low grit scores. Providing interventions such as resilience training [ 31 , 32 ], mentorship programs [ 33 ], and periodic psychological assessments for residents with low grit may be beneficial in supporting residents' mental health. These proactive approaches may enhance individual well-being and improve overall residency program outcomes by reducing attrition rates and improving clinical performance. Conclusion In conclusion, low grit scores at the start of a job were significantly associated with one-year-later depressive symptoms at the end of the PGY1 residency among Japanese PGY1 residents. These findings suggest that grit is an important protective factor against depressive symptoms among resident physicians. Further research is needed to examine whether interventions aimed at increasing grit during residency training can prevent depressive symptoms and other mental health problems among resident physicians. Abbreviations PGY1: first-year postgraduate; TMDU: Tokyo Medical and Dental University; Grit-S: Short Grit Scale; CES-D: Center for Epidemiologic Studies Depression Scale; RR: relative risk; CI: confidence interval. Declarations Ethical approval and consent to participate This study was approved by the Institutional Review Board of Tokyo Medical and Dental University (IRB approval number M2019-283). We obtained informed consent from all participants before participation in the study. We conducted this study in accordance with the Declaration of Helsinki. Consent for publication Participants were made aware of the purpose of the research and how their data would be used, ensuring their confidentiality and anonymity throughout the process. By agreeing to participate, the participants also consented to the publication of the study’s findings. Availability of data and materials Data from this study will be available on reasonable request from the corresponding author. Competing interests The authors report no conflict of interest. Funding This work was supported by Ministry of Health, Labour and Welfare Research Grant Number 24AC1002. The grant was awarded to MY. Contributions NN, YA, EO, AK, and MY acquired and designed the study. TN analyzed the study and drafted the work. NN substantively revised the study. TF and MY approve the submitted version and agree to be personally accountable. All authors read and approved the manuscript. Acknowledgements We are grateful to staffs at Department of Professional Development, Institute of Science Tokyo Hospital for assisting with survey collection. Author information Authors and Affiliations Department of Medical Education Research and Development, Institute of Science Tokyo, Tokyo, Japan Toshinori Nishizawa, Yu Akaishi, Eriko Okada, Ayako Kashimada, & Masanaga Yamawaki Department of Public Health, Institute of Science Tokyo, Tokyo, Japan Toshinori Nishizawa, Nobutoshi Nawa, & Takeo Fujiwara Department of Professional Development, Institute of Science Tokyo Hospital, Tokyo, Japan Yu Akaishi, Eriko Okada, & Ayako Kashimada Email: [email protected] Correspondence Author Correspondence to Masanaga Yamawaki References Dyrbye LN, West CP, Satele D, Boone S, Tan L, Sloan J, Shanafelt TD: Burnout among U.S. medical students, residents, and early career physicians relative to the general U.S. population . Acad Med 2014, 89 (3):443-451. Crudden G, Margiotta F, Doherty AM: Physician burnout and symptom of anxiety and depression: Burnout in Consultant Doctors in Ireland Study (BICDIS) . PLoS One 2023, 18 (3):e0276027. 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Cite Share Download PDF Status: Published Journal Publication published 19 Jul, 2025 Read the published version in BMC Medical Education → Version 1 posted Editorial decision: Revision requested 12 Jun, 2025 Reviewers agreed at journal 10 Jun, 2025 Reviews received at journal 09 Jun, 2025 Reviews received at journal 08 Jun, 2025 Reviewers agreed at journal 08 Jun, 2025 Reviewers agreed at journal 29 May, 2025 Reviewers invited by journal 26 May, 2025 Editor assigned by journal 23 May, 2025 Submission checks completed at journal 22 May, 2025 First submitted to journal 22 May, 2025 You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. 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Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-6631869","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":462441986,"identity":"c3e278d3-8038-4454-b5d2-b9d48a9ce793","order_by":0,"name":"Toshinori Nishizawa","email":"","orcid":"","institution":"Department of Medical Education Research and Development, Institute of Science Tokyo","correspondingAuthor":false,"prefix":"","firstName":"Toshinori","middleName":"","lastName":"Nishizawa","suffix":""},{"id":462441987,"identity":"887b225e-3d2c-4173-9acb-afe5eedae379","order_by":1,"name":"Nobutoshi Nawa","email":"","orcid":"","institution":"Department of Public Health, Institute of Science Tokyo","correspondingAuthor":false,"prefix":"","firstName":"Nobutoshi","middleName":"","lastName":"Nawa","suffix":""},{"id":462441988,"identity":"a2fc9b41-fb88-4520-bd27-975b953487ad","order_by":2,"name":"Yu Akaishi","email":"","orcid":"","institution":"Department of Medical Education Research and Development, Institute of Science Tokyo","correspondingAuthor":false,"prefix":"","firstName":"Yu","middleName":"","lastName":"Akaishi","suffix":""},{"id":462441989,"identity":"d2711cf7-3940-4b7d-92a8-26fd557d32b7","order_by":3,"name":"Eriko Okada","email":"","orcid":"","institution":"Department of Medical Education Research and Development, Institute of Science Tokyo","correspondingAuthor":false,"prefix":"","firstName":"Eriko","middleName":"","lastName":"Okada","suffix":""},{"id":462441990,"identity":"1d56db9a-4ae2-4828-baee-06da0368f82d","order_by":4,"name":"Ayako Kashimada","email":"","orcid":"","institution":"Department of Medical Education Research and Development, Institute of Science Tokyo","correspondingAuthor":false,"prefix":"","firstName":"Ayako","middleName":"","lastName":"Kashimada","suffix":""},{"id":462441991,"identity":"9d5a2768-e850-4500-bf6e-de7d25dd1ed1","order_by":5,"name":"Takeo Fujiwara","email":"","orcid":"","institution":"Department of Public Health, Institute of Science Tokyo","correspondingAuthor":false,"prefix":"","firstName":"Takeo","middleName":"","lastName":"Fujiwara","suffix":""},{"id":462441992,"identity":"0c75c362-ac79-41b1-b8b6-f728a20d59d5","order_by":6,"name":"Masanaga Yamawaki","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAAzElEQVRIiWNgGAWjYBADxn4gIQFmNRCrZWYbyVo2HINqIQh0ZyQ/3XSj4p7s5vvdiTcYauwYmGcTsMbsRprZ7ZwzxcbbjvFutmA4lszAOOcAIS0JZrdz2xISgVq2STCwHWBgnJFASEv6t9u5/xISN7eBtPwjSksO0JaGhMQNbEAtjG3EaDnzpux2zrEE4xnHcjdbJPYl8xD2y/H0bbdzahJk+5vPbrzx4ZudnCGhEGMQQHYGkM1jOIOADgZ+dGfIExeho2AUjIJRMIIAACKMSwcK2M8KAAAAAElFTkSuQmCC","orcid":"","institution":"Department of Medical Education Research and Development, Institute of Science Tokyo","correspondingAuthor":true,"prefix":"","firstName":"Masanaga","middleName":"","lastName":"Yamawaki","suffix":""}],"badges":[],"createdAt":"2025-05-10 01:53:14","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-6631869/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-6631869/v1","draftVersion":[],"editorialEvents":[{"content":"https://doi.org/10.1186/s12909-025-07651-4","type":"published","date":"2025-07-19T16:05:15+00:00"}],"editorialNote":"","failedWorkflow":false,"files":[{"id":83558093,"identity":"1d8ee655-e1c2-42d7-b37d-6d3eecc83a6a","added_by":"auto","created_at":"2025-05-28 12:38:03","extension":"png","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":473129,"visible":true,"origin":"","legend":"\u003cp\u003eFlow chart of the participants included in the study.\u003c/p\u003e","description":"","filename":"1.png","url":"https://assets-eu.researchsquare.com/files/rs-6631869/v1/93e17969bf8a7037f13412fc.png"},{"id":88506082,"identity":"2fcf4dbf-6b3f-46d2-852a-307ea15b4a20","added_by":"auto","created_at":"2025-08-07 07:30:40","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":2672110,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-6631869/v1/dfa475a6-9bd0-44e2-807e-dbc5a2b45a06.pdf"}],"financialInterests":"No competing interests reported.","formattedTitle":"Association between Grit at the Start of Residency and Depressive Symptoms at the End of Residency Among Postgraduate Year 1 Medical Residents in Japan: A Longitudinal Study","fulltext":[{"header":"Introduction","content":"\u003cp\u003eThe medical profession is inherently stressful, with a high prevalence of depression, burnout, and other mental health issues [\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e, \u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e]. Resident physicians, in particular, are at an elevated risk of developing depressive symptoms due to their recent transition from medical student to resident physicians, and lack of communication skills, medical knowledge, and experience [\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e]. In a large cross-sectional survey in Japan, 22.6% of first-year postgraduate (PGY1) residents had new depressive symptoms after 3 months of training [\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e]. Residents having depressive symptoms tend to make more medical errors than those without​​ [\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e, \u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e, \u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e]. Thus, it is crucial to identify residents at risk of depression to provide preventive and timely support.\u003c/p\u003e \u003cp\u003eGrit is the passion and perseverance for long-term goals, as coined and defined by Angela Duckworth [\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e]. Grit has garnered significant attention in the medical literature for its positive association with academic achievement, career success, and psychological well-being, as well as its negative association with depression, burnout, and residency attrition [\u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e]. In Japan, our previous cross-sectional study has shown that PGY1 residents with high grit scores have lower depressive symptoms compared to those with lower scores at the beginning of a job [\u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e]. Our other cross-sectional study also reported that the Grit total score and two subscales, such as perseverance of effort and consistency of interest scores, were inversely associated with depressive symptoms in medical students [\u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e]. The cross-sectional study from the USA showed that among surgical residents, high grit was inversely associated with depression as well as positively predictive of psychological well-being [\u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eAlthough several studies have demonstrated the association between Grit and depression among resident physicians [\u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e, \u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e], there is a lack of longitudinal studies. Cross-sectional studies provide valuable insights, but in a cross-sectional design, there is the potential for reverse causality, with individuals with higher depressive symptoms responding lower on grit score. Longitudinal studies will allow researchers to examine whether grit at the start of residency is associated with lower levels of depression later, after adjusting for depressive symptoms present at the beginning of residency. This can inform the development of targeted interventions to support residents' well-being. This study aims to fill the gap in the literature by conducting a longitudinal study that examine the association between grit at the start of residency and depressive symptoms at the end of the PGY1 residency among first-year medical residents in Japan.\u003c/p\u003e"},{"header":"Methods","content":"\u003cdiv id=\"Sec3\" class=\"Section2\"\u003e \u003ch2\u003eStudy Participants\u003c/h2\u003e \u003cp\u003eWe conducted this longitudinal cohort study at Tokyo Medical and Dental University (TMDU) in Tokyo, Japan. The study initially recruited all PGY1 residents (N\u0026thinsp;=\u0026thinsp;284) who joined the TMDU resident program in 2021, 2022, and 2023​​. We performed the baseline online survey approximately at the start of the PGY1 residency in April. We conducted the follow-up survey at the end of the PGY1 residency in March. The online survey, administered in Japanese, included items assessing Grit using the Japanese version of the Short Grit Scale (Grit-S) [\u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e], depressive symptoms using the Japanese version of the Center for Epidemiologic Studies Depression Scale (CES-D) [\u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e], and other covariates, all adapted from a prior cross-sectional study [\u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e]. Japanese residency programs provide a comprehensive 2-year training experience that requires all residents to rotate through major specialties at approved hospitals throughout Japan. The TMDU residency program is divided into mainly two distinct types. Program 1 provides PGY1 training in TMDU Hospital, an academic medical center and tertiary emergency medical facility, and PGY2 training in a community-based hospital. Program 2 provides PGY1 training in a community-based hospital and PGY2 training in TMDU Hospital. This program has been a standard practice since 2004​​ [\u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e]. We conducted this study in accordance with the Declaration of Helsinki, which was approved by the Institutional Review Board of Tokyo Medical and Dental University (IRB approval number M2019-283). We obtained informed consent from all participants before participation in the study​​. We excluded residents who did not consent or failed to complete all of the surveys. Therefore, residents who participated in this study have no missing values in this study.\u003c/p\u003e \u003c/div\u003e\n\u003ch3\u003eGrit\u003c/h3\u003e\n\u003cp\u003eAt the start of the PGY1 residency, we measured grit among PGY1 residents using the Japanese version of the Grit-S, which was verified for factor structure, reliability, and validity among 1043 Japanese university students [\u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e]. Grit-S was designed as a modified version of the original Grit Scale [\u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e15\u003c/span\u003e] and consisted of eight items using a five-point Likert scale ranging from 1 to 5 [\u003cspan citationid=\"CR16\" class=\"CitationRef\"\u003e16\u003c/span\u003e]. Final scores were added up for each question and divided by the number of questions, ranging from 1 (not at all gritty) to 5 (extremely gritty). The scores of the two subscales, namely the perseverance of effort and consistency of interest, consist of four items with similar score ranges of the total grit score. Grit-S was validated for internal consistency, test\u0026ndash;retest stability, and predictive validity of this scale [\u003cspan citationid=\"CR16\" class=\"CitationRef\"\u003e16\u003c/span\u003e]. Cronbach\u0026rsquo;s alpha of our study was 0.75, 075, and 0.65 for Grit-S, perseverance of effort, and consistency of interest scores, respectively. The continuous Grit-S, perseverance of effort, and consistency of interest scores were used for the analysis. The Grit-S was measured at the baseline survey ​.\u003c/p\u003e\n\u003ch3\u003eDepressive Symptoms\u003c/h3\u003e\n\u003cp\u003eWe measured depressive symptoms using the Japanese version of the CES-D [\u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e], which was validated using the original CES-D, a widely recognized scale for assessing depressive symptoms over the past week [\u003cspan citationid=\"CR17\" class=\"CitationRef\"\u003e17\u003c/span\u003e]. We defined a score of \u0026ge;\u0026thinsp;16 on the CES-D as indicative of depressive symptoms [\u003cspan citationid=\"CR18\" class=\"CitationRef\"\u003e18\u003c/span\u003e] and utilized the scale as a categorical variable in the analysis​​​​. In a validation study of the Japanese version of the CES-D, a cut-off score of 16 demonstrated a sensitivity of 88.2% and a specificity of 84.8% [\u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e]. We collected the CES-D by administering online surveys at two time points (at the start and the end of the PGY1 residency).\u003c/p\u003e\n\u003ch3\u003eCovariates\u003c/h3\u003e\n\u003cp\u003eWe collected several covariates from the basic data at the start of the PGY1 residency, including demographic variables such as age, sex, start year of training, type of training program, and name of graduated university. We obtained the type of residency program to see if the PGY1 training environment is different TMDU hospital from community-based hospital. The name of the graduated university was identified to assess familiarity with the training environment, as residents who graduated from TMDU are more familiar due to their clinical clerkship at TMDU hospital. In addition, lifestyle factors were collected from the online baseline survey at the start of the PGY1 residency, including average sleeping hours on weekdays, smoking habits (categorized as never, past smoker, or current smoker), drinking habits (categorized as never, only a few times a month, or more than a few times a week), frequency of eating breakfast (categorized as every day, more than several times a week, or less than a few times a week), and frequency of exercise within the last month (categorized as almost never, less than a few times a week, or more than several times a week).\u003c/p\u003e \u003cdiv id=\"Sec7\" class=\"Section2\"\u003e \u003ch2\u003eStatistical Analysis\u003c/h2\u003e \u003cp\u003eWe calculated descriptive statistics for all variables to compare differences between groups. We used Poisson regression with robust error variance to evaluate the association between baseline grit scores and the presence of depressive symptoms at the end of PGY1. In addition, we also evaluated the association between the Grit-S subscales, perseverance of effort and consistency of interest, and the presence of depressive symptoms at the end of PGY1. We adjusted for potential confounders, including baseline depressive state, age, sex, university attended, average weekday sleeping hours, ​​and type of residency program [\u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e, \u003cspan citationid=\"CR19\" class=\"CitationRef\"\u003e19\u003c/span\u003e]. We presented the results as relative risk (RR) with 95% confidence interval (CI), and statistical significance was set at a p-value of \u0026lt;\u0026thinsp;0.05. We conducted all analyses using Stata version 17.0 (Stata Corp LLC, College Station, TX, USA)​​.\u003c/p\u003e \u003c/div\u003e"},{"header":"Results","content":"\u003cp\u003eAs shown in Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003e, between April 2021 and March 2024, 284 PGY1 residents joined the TMDU resident program. Residents who disagreed to participate in the study (N\u0026thinsp;=\u0026thinsp;2), who had no response at the baseline survey (N\u0026thinsp;=\u0026thinsp;50) and at the follow-up survey (N\u0026thinsp;=\u0026thinsp;73), and who had missing value at the baseline survey (N\u0026thinsp;=\u0026thinsp;9) and at the follow-up survey (N\u0026thinsp;=\u0026thinsp;4) were excluded from the study. As a result, 146 residents were included in the analysis.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003eAs shown in Table\u0026nbsp;\u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\u003e, among 146 residents, 28 (19.2%) residents were categorized as depressed group at the end of the PGY1 residency. The Grit-S score at the baseline was significantly lower in the depressed group (mean: 2.96\u0026thinsp;\u0026plusmn;\u0026thinsp;0.55) compared to the non-depressed group (mean: 3.31\u0026thinsp;\u0026plusmn;\u0026thinsp;0.59). Regarding Grit-S subscales, the perseverance of effort score of the depressed group was significantly lower than that of the non-depressed group (3.25\u0026thinsp;\u0026plusmn;\u0026thinsp;0.68 vs. 3.58\u0026thinsp;\u0026plusmn;\u0026thinsp;0.69). The consistency of interest score was significantly lower in the depressed group (mean: 2.66\u0026thinsp;\u0026plusmn;\u0026thinsp;0.62) compared to the non-depressed group (mean: 3.03\u0026thinsp;\u0026plusmn;\u0026thinsp;0.75). Additionally, a higher percentage of residents in the depressed group were identified as depressed at baseline (50.0%) compared to the non-depressed group (14.4%).\u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab1\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 1\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003eCharacteristics of study participants.\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"4\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003eDepressed\u003c/p\u003e \u003cp\u003eN\u0026thinsp;=\u0026thinsp;28 (19.2)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003eNon-Depressed\u003c/p\u003e \u003cp\u003eN\u0026thinsp;=\u0026thinsp;118 (80.8)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e \u003cp\u003ep-value\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eAge (years), mean (SD)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e25.2 (1.33)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e24.9 (1.92)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.440\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eSex, n (%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eMale\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e18 (64.3)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e67 (56.8)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.469\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eFemale\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e10 (35.7)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e51 (43.2)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eStart year of training, n (%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.809\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e2021\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e9 (32.1)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e40 (33.9)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e2022\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e7 (25.0)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e23 (19.5)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e2023\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e12 (42.9)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e55 (46.6)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eGraduated university, n (%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.936\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eTMDU\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e14 (50.0)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e58 (49.2)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eOthers\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e14 (50.0)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e60 (50.8)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eType of residency program\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.371\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eProgram 1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e11 (39.3)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e36 (30.5)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eProgram 2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e17 (60.7)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e82 (69.5)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eMarriage, n (%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0 (0)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e5 (4.2)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.583\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePresence of family living together, n (%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e1 (3.6)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e20 (17.0)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.078\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eWeekday sleeping hours, mean (SD)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e7.26 (1.22)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e7.32 (0.90)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.764\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eSmoking habits, n (%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.051\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eNever\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e27 (96.4)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e109 (92.4)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePast smoker\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0 (0)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e9 (7.6)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eCurrent smoker\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e1 (3.6)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0 (0)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eDrinking habits, n (%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.066\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eNever\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e6 (21.4)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e16 (13.6)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eOnly a few times a month\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e18 (64.3)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e60 (50.9)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eMore than a few times a week\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e4 (14.3)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e42 (35.6)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eFrequency of eating breakfast, n (%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.454\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eEvery day\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e21 (75.0)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e78 (66.1)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eMore than several times a week\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e2 (7.1)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e21 (17.8)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eLess than a few times a week\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e5 (17.9)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e19 (16.1)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eFrequency of exercise within the last month, n (%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.143\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eMore than several times a week\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e3 (10.7)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e33 (28.0)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eLess than a few times a week\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e11 (39.3)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e33 (28.0)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eAlmost never\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e14 (50.0)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e52 (44.0)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eGrit-S, mean (SD)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e2.96 (0.55)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e3.31 (0.59)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e\u003cb\u003e0.005\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePerseverance of Effort, mean (SD)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e3.25 (0.68)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e3.58 (0.69)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e\u003cb\u003e0.023\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eConsistency of Interest, mean (SD)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e2.66 (0.62)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e3.03 (0.75)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e\u003cb\u003e0.016\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eDepressed at baseline, n (%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e14 (50.0)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e17 (14.4)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e\u003cb\u003e\u0026lt;\u0026thinsp;0.001\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colspan=\"4\" nameend=\"c4\" namest=\"c1\"\u003e \u003cp\u003eBold indicates p\u0026thinsp;\u0026lt;\u0026thinsp;0.05.\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003cp\u003eAs shown in Table\u0026nbsp;\u003cspan refid=\"Tab2\" class=\"InternalRef\"\u003e2\u003c/span\u003e, the crude analysis revealed an association between a one-unit increase in the Grit-S score at baseline and a 53% reduction in the risk of having depressive symptoms at the end of PGY1 (RR: 0.47; 95% CI: 0.29\u0026ndash;0.74). After further adjusting for depressive symptoms at baseline, age, sex, graduated university, weekday sleeping hours, and type of residency program [\u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e, \u003cspan citationid=\"CR19\" class=\"CitationRef\"\u003e19\u003c/span\u003e], a one-unit increase in the Grit-S score was associated with a 42% reduction in the risk of having depressive symptoms (RR: 0.58; 95% CI: 0.37\u0026ndash;0.88).\u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab2\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 2\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003eAdjusted relative risk ratio for association between depressed state at the end of PGY1 and Grit-S score.\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"5\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/th\u003e \u003cth align=\"left\" colspan=\"2\" nameend=\"c3\" namest=\"c2\"\u003e \u003cp\u003eCrude\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colspan=\"2\" nameend=\"c5\" namest=\"c4\"\u003e \u003cp\u003eAdjusted\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eRelative risk\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e95%CI\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003eRelative risk\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e95%CI\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eGrit-S\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e\u003cb\u003e0.47\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e\u003cb\u003e0.29\u0026ndash;0.74\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e\u003cb\u003e0.58\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e\u003cb\u003e0.37\u0026ndash;0.88\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colspan=\"5\" nameend=\"c5\" namest=\"c1\"\u003e \u003cp\u003eAdjusted for depressed state at baseline, age, sex, graduated university, weekday sleeping hours, and type of residency program. Bold indicates p\u0026thinsp;\u0026lt;\u0026thinsp;0.05.\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003cp\u003eAs shown in Table\u0026nbsp;\u003cspan refid=\"Tab3\" class=\"InternalRef\"\u003e3\u003c/span\u003e, the crude analysis indicated that a one-unit increase in the perseverance of effort score was associated with a 39% reduction in the risk of having depressive symptoms at the end of PGY1 (RR: 0.61; 95% CI: 0.41\u0026ndash;0.89). Similarly, the crude analysis showed that a one-unit increase in the consistency of interest score was significantly associated with a 43% reduction in risk (RR: 0.57; 95% CI: 0.39\u0026ndash;0.83). Furthermore, after further adjusting for depressive symptoms at baseline, age, sex, graduated university, weekday sleeping hours, and type of residency program [\u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e, \u003cspan citationid=\"CR19\" class=\"CitationRef\"\u003e19\u003c/span\u003e], the perseverance of effort score was significantly associated with a lower risk of having depressive symptoms (RR: 0.68; 95% CI: 0.48\u0026ndash;0.96), as well as the consistency of interest score (RR: 0.70; 95% CI: 0.49\u0026ndash;0.99).\u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab3\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 3\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003eAdjusted relative risk ratio for association between depressed state at the end of PGY1 and Grit-S subscale scores.\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"5\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/th\u003e \u003cth align=\"left\" colspan=\"2\" nameend=\"c3\" namest=\"c2\"\u003e \u003cp\u003eCrude\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colspan=\"2\" nameend=\"c5\" namest=\"c4\"\u003e \u003cp\u003eAdjusted\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eRelative risk\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e95%CI\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003eRelative risk\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e95%CI\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePerseverance of effort\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e\u003cb\u003e0.61\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e\u003cb\u003e0.41\u0026ndash;0.89\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e\u003cb\u003e0.68\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e\u003cb\u003e0.48\u0026ndash;0.96\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eConsistency of interest\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e\u003cb\u003e0.57\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e\u003cb\u003e0.39\u0026ndash;0.83\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e\u003cb\u003e0.70\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e\u003cb\u003e0.49\u0026ndash;0.99\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colspan=\"5\" nameend=\"c5\" namest=\"c1\"\u003e \u003cp\u003eAdjusted for depressed state at baseline, age, sex, graduated university, weekday sleeping hours, and type of residency program. Bold indicates p\u0026thinsp;\u0026lt;\u0026thinsp;0.05.\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e"},{"header":"Discussion","content":"\u003cp\u003eIn this longitudinal study, we found that higher baseline grit scores among PGY1 residents were significantly associated with a reduced risk of developing depressive symptoms by the end of their PGY1 residency. This association remained significant even after adjusting for baseline depressive symptoms and other covariates such as age, sex, university attended, average weekday sleeping hours, and type of residency program. Our findings were consistent with the previous cross-sectional studies suggesting a protective effect of grit against depressive symptoms in Japan and the USA [\u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e, \u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eOur previous cross-sectional study indicated that after adjusting for age, sex, graduated university, and weekday sleeping hours, Japanese PGY1 residents with higher grit scores reported lower levels of depression at the time of the job start (adjusted odds ratio, 0.37; 95% CI, 0.19\u0026ndash;0.74) [\u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e]. The cross-sectional study from the USA also showed that among surgical residents, grit was significantly inversely predictive of depression (coefficient (b) for the total grit score = \u0026minus;\u0026thinsp;0.28, p\u0026thinsp;\u0026lt;\u0026thinsp;0.01) after adjusting for age, gender, ethnicity, and marital status [\u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e]. Moreover, the longitudinal study from the USA indicated that grit at baseline was significantly associated with lower rates of burnout six months later than those with less grit after adjusting for gender and baseline burnout among surgical residents (b = \u0026minus;\u0026thinsp;0.20, p\u0026thinsp;=\u0026thinsp;0.01) [\u003cspan citationid=\"CR20\" class=\"CitationRef\"\u003e20\u003c/span\u003e]. However, no longitudinal studies examined whether grit was associated with later depressive symptoms during residency training after adjusting for baseline depression. Because there is the potential for reverse causality in a cross-sectional design, our longitudinal study adds to the literature by demonstrating that higher grit serves as a predictor of one-year-later depressive symptoms in a clinical training setting.\u003c/p\u003e \u003cp\u003eThe following pathways may explain how high grit serves as a protective factor against depressive symptoms. First, occupational stress mediates the relationship between grit and depression [\u003cspan citationid=\"CR21\" class=\"CitationRef\"\u003e21\u003c/span\u003e]. Individuals with high levels of grit can recover from negative emotions to positive emotions faster [\u003cspan citationid=\"CR22\" class=\"CitationRef\"\u003e22\u003c/span\u003e], have lower psychological exhaustion [\u003cspan citationid=\"CR20\" class=\"CitationRef\"\u003e20\u003c/span\u003e], and use a negative event as an opportunity for growth more [\u003cspan citationid=\"CR21\" class=\"CitationRef\"\u003e21\u003c/span\u003e]. Also, individuals with high levels of grit may know how to cope in a stressful environment and have increased psychological security [\u003cspan citationid=\"CR23\" class=\"CitationRef\"\u003e23\u003c/span\u003e]. This can reduces interpersonal stress, thereby resulting in less risk for depression [\u003cspan citationid=\"CR23\" class=\"CitationRef\"\u003e23\u003c/span\u003e]. Second, presence of meaning in life may mediate the association between grit and depression [\u003cspan citationid=\"CR24\" class=\"CitationRef\"\u003e24\u003c/span\u003e]. Individuals with high levels of grit are more likely to realize that life is meaningful and to stay motivated in looking for the meaning of their lives, and are therefore less likely to experience maladaptive emotional states. Third, mindfulness may mediate the association between grit and subject well-being [\u003cspan citationid=\"CR25\" class=\"CitationRef\"\u003e25\u003c/span\u003e, \u003cspan citationid=\"CR26\" class=\"CitationRef\"\u003e26\u003c/span\u003e]. Individuals with high levels of grit have higher levels of mindfulness, which might have been protective against depressive symptoms. Future research should examine whether occupational stress, presence of meaning in life, and mindfulness mediates the association between grit and depressive symptoms among medical residents, which we were not able to evaluate in this study.\u003c/p\u003e \u003cp\u003eFinally, we found that two subscales of grit were inversely associated with depressive symptoms. These results were consistent with cross-sectional study that showed Grit-S subscales, perseverance of effort and consistency of interest, were significantly associated with lower depressive symptoms among Japanese medical students after adjusting for sex, age, and survey year [\u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e]. Our study adds to the literature by demonstrating the association using longitudinal design. While perseverance of effort may be associated with academic engagement, subjective well-being [\u003cspan citationid=\"CR27\" class=\"CitationRef\"\u003e27\u003c/span\u003e], and authentic pride [\u003cspan citationid=\"CR28\" class=\"CitationRef\"\u003e28\u003c/span\u003e], consistency of interest may be associated with reduced psychological distress [\u003cspan citationid=\"CR29\" class=\"CitationRef\"\u003e29\u003c/span\u003e, \u003cspan citationid=\"CR30\" class=\"CitationRef\"\u003e30\u003c/span\u003e]. These results underscore the importance of fostering both subscales of grit to reduce the risk of developing depressive symptoms.\u003c/p\u003e \u003cp\u003eOur study has important strengths. This is the first longitudinal study to evaluate the impact of grit on one-year later depressive symptoms after adjusting for baseline depressive states and other covariates. However, there are several limitations to consider. First, the study was conducted at a single institution, which may limit the generalizability of our results to other residency programs. Second, self-reported measures of grit and depressive symptoms could introduce response biases, such as social desirability bias, impacting the validity of the data collected. Third, the type of the residency program was adjusted, but this study could not assess the training details. Finally, we utilized a self-administered questionnaire and identified residents who had a CES-D score of 16 or higher, categorized as positive for depressive symptoms. It is important to note that this does not mean a formal diagnosis of depression.\u003c/p\u003e"},{"header":"Implications","content":"\u003cp\u003eIn this study, we demonstrated that low grit scores at the start of a job were significantly associated with depressive symptoms at the end of the PGY1 residency. Residency program directors should evaluate grit scores for resident physicians at the start of employment and closely follow residents with low grit scores. Providing interventions such as resilience training [\u003cspan citationid=\"CR31\" class=\"CitationRef\"\u003e31\u003c/span\u003e, \u003cspan citationid=\"CR32\" class=\"CitationRef\"\u003e32\u003c/span\u003e], mentorship programs [\u003cspan citationid=\"CR33\" class=\"CitationRef\"\u003e33\u003c/span\u003e], and periodic psychological assessments for residents with low grit may be beneficial in supporting residents' mental health. These proactive approaches may enhance individual well-being and improve overall residency program outcomes by reducing attrition rates and improving clinical performance.\u003c/p\u003e"},{"header":"Conclusion","content":"\u003cp\u003eIn conclusion, low grit scores at the start of a job were significantly associated with one-year-later depressive symptoms at the end of the PGY1 residency among Japanese PGY1 residents. These findings suggest that grit is an important protective factor against depressive symptoms among resident physicians. Further research is needed to examine whether interventions aimed at increasing grit during residency training can prevent depressive symptoms and other mental health problems among resident physicians.\u003c/p\u003e"},{"header":"Abbreviations","content":"\u003cp\u003ePGY1: first-year postgraduate; TMDU: Tokyo Medical and Dental University; Grit-S: Short Grit Scale; CES-D: Center for Epidemiologic Studies Depression Scale; RR: relative risk; CI: confidence interval.\u003c/p\u003e\n"},{"header":"Declarations","content":"\u003cp\u003e\u003cstrong\u003eEthical approval and consent to participate\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThis study was approved by the Institutional Review Board of Tokyo Medical and Dental University (IRB approval number M2019-283). We obtained informed consent from all participants before participation in the study. We conducted this study in accordance with the Declaration of Helsinki.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConsent for publication\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eParticipants were made aware of the purpose of the research and how their data would be used, ensuring their confidentiality and anonymity throughout the process. By agreeing to participate, the participants also consented to the publication of the study\u0026rsquo;s findings.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAvailability of data and materials\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eData from this study will be available on reasonable request from the corresponding author.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eCompeting interests\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe authors report no conflict of interest.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eFunding\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThis work was supported by Ministry of Health, Labour and Welfare Research Grant Number 24AC1002. The grant was awarded to MY.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eContributions\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eNN, YA, EO, AK, and MY acquired and designed the study. TN analyzed the study and drafted the work. NN substantively revised the study. TF and MY approve the submitted version and agree to be personally accountable. All authors read and approved the manuscript.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAcknowledgements\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eWe are grateful to staffs at Department of Professional Development, Institute of Science Tokyo Hospital for assisting with survey collection.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAuthor information\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAuthors and Affiliations\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eDepartment of Medical Education Research and Development, Institute of Science Tokyo, Tokyo, Japan\u003c/p\u003e\n\u003cp\u003eToshinori Nishizawa, Yu Akaishi, Eriko Okada, Ayako Kashimada, \u0026amp; Masanaga Yamawaki\u003c/p\u003e\n\u003cp\u003eDepartment of Public Health, Institute of Science Tokyo, Tokyo, Japan\u003c/p\u003e\n\u003cp\u003eToshinori Nishizawa, Nobutoshi Nawa, \u0026amp; Takeo Fujiwara\u003c/p\u003e\n\u003cp\u003eDepartment of Professional Development, Institute of Science Tokyo Hospital, Tokyo, Japan\u003c/p\u003e\n\u003cp\u003eYu Akaishi, Eriko Okada, \u0026amp; Ayako Kashimada\u003c/p\u003e\n\u003cp\u003eEmail: [email protected]\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eCorrespondence Author\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eCorrespondence to\u0026nbsp;Masanaga Yamawaki\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\n\u003cli\u003eDyrbye LN, West CP, Satele D, Boone S, Tan L, Sloan J, Shanafelt TD: \u003cstrong\u003eBurnout among U.S. medical students, residents, and early career physicians relative to the general U.S. population\u003c/strong\u003e. \u003cem\u003eAcad Med \u003c/em\u003e2014, \u003cstrong\u003e89\u003c/strong\u003e(3):443-451.\u003c/li\u003e\n\u003cli\u003eCrudden G, Margiotta F, Doherty AM: \u003cstrong\u003ePhysician burnout and symptom of anxiety and depression: Burnout in Consultant Doctors in Ireland Study (BICDIS)\u003c/strong\u003e. \u003cem\u003ePLoS One \u003c/em\u003e2023, \u003cstrong\u003e18\u003c/strong\u003e(3):e0276027.\u003c/li\u003e\n\u003cli\u003eSen S, Kranzler HR, Krystal JH, Speller H, Chan G, Gelernter J, Guille C: \u003cstrong\u003eA prospective cohort study investigating factors associated with depression during medical internship\u003c/strong\u003e. \u003cem\u003eArch Gen Psychiatry \u003c/em\u003e2010, \u003cstrong\u003e67\u003c/strong\u003e(6):557-565.\u003c/li\u003e\n\u003cli\u003eOgawa R, Seo E, Maeno T, Ito M, Sanuki M, Maeno T: \u003cstrong\u003eThe relationship between long working hours and depression among first-year residents in Japan\u003c/strong\u003e. \u003cem\u003eBMC Med Educ \u003c/em\u003e2018, \u003cstrong\u003e18\u003c/strong\u003e(1):50.\u003c/li\u003e\n\u003cli\u003eFahrenkopf AM, Sectish TC, Barger LK, Sharek PJ, Lewin D, Chiang VW, Edwards S, Wiedermann BL, Landrigan CP: \u003cstrong\u003eRates of medication errors among depressed and burnt out residents: prospective cohort study\u003c/strong\u003e. \u003cem\u003eBmj \u003c/em\u003e2008, \u003cstrong\u003e336\u003c/strong\u003e(7642):488-491.\u003c/li\u003e\n\u003cli\u003eBrunsberg KA, Landrigan CP, Garcia BM, Petty CR, Sectish TC, Simpkin AL, Spector ND, Starmer AJ, West DC, Calaman S: \u003cstrong\u003eAssociation of Pediatric Resident Physician Depression and Burnout With Harmful Medical Errors on Inpatient Services\u003c/strong\u003e. \u003cem\u003eAcad Med \u003c/em\u003e2019, \u003cstrong\u003e94\u003c/strong\u003e(8):1150-1156.\u003c/li\u003e\n\u003cli\u003eDuckworth A: \u003cstrong\u003eGrit: The Power of Passion and Perseverance.\u003c/strong\u003e New York: Scribner; 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Society \u003c/em\u003e2018, \u003cstrong\u003e51\u003c/strong\u003e(6):865-876.\u003c/li\u003e\n\u003cli\u003eLi J, Lin L, Zhao Y, Chen J, Wang S: \u003cstrong\u003eGrittier Chinese adolescents are happier: The mediating role of mindfulness\u003c/strong\u003e. \u003cem\u003ePersonality and Individual Differences \u003c/em\u003e2018, \u003cstrong\u003e131\u003c/strong\u003e:232-237.\u003c/li\u003e\n\u003cli\u003eHofmann SG, G\u0026oacute;mez AF: \u003cstrong\u003eMindfulness-Based Interventions for Anxiety and Depression\u003c/strong\u003e. \u003cem\u003ePsychiatr Clin North Am \u003c/em\u003e2017, \u003cstrong\u003e40\u003c/strong\u003e(4):739-749.\u003c/li\u003e\n\u003cli\u003eDatu JAD, Valdez JPM, King RB: \u003cstrong\u003ePerseverance Counts but Consistency Does Not! Validating the Short Grit Scale in a Collectivist Setting\u003c/strong\u003e. \u003cem\u003eCurrent Psychology \u003c/em\u003e2016, \u003cstrong\u003e35\u003c/strong\u003e(1):121-130.\u003c/li\u003e\n\u003cli\u003eVan Doren N, Tharp JA, Johnson SL, Staudenmaier PJ, Anderson C, Freeman MA: \u003cstrong\u003ePerseverance of effort is related to lower depressive symptoms via authentic pride and perceived power\u003c/strong\u003e. \u003cem\u003ePersonality and Individual Differences \u003c/em\u003e2019, \u003cstrong\u003e137\u003c/strong\u003e:45-49.\u003c/li\u003e\n\u003cli\u003ePeng X, Wu D: \u003cstrong\u003eThe protective effect of grit on clinical nurses\u0026apos; occupational psychological distress: Mediating and suppressing effects of Hope\u003c/strong\u003e. \u003cem\u003eFront Psychol \u003c/em\u003e2022, \u003cstrong\u003e13\u003c/strong\u003e:1019655.\u003c/li\u003e\n\u003cli\u003eMasuyama A, Kubo T, Sugawara D, Chishima Y: \u003cstrong\u003eInterest Consistency Can Buffer the Effect of COVID-19 Fear on Psychological Distress\u003c/strong\u003e. \u003cem\u003eInt J Ment Health Addict \u003c/em\u003e2022, \u003cstrong\u003e20\u003c/strong\u003e(5):3044-3055.\u003c/li\u003e\n\u003cli\u003eKhedr MA, Alharbi TAF, Alkaram AA, Hussein RM: \u003cstrong\u003eImpact of resilience-based intervention on emotional regulation, grit and life satisfaction among female Egyptian and Saudi nursing students: A randomized controlled trial\u003c/strong\u003e. \u003cem\u003eNurse Educ Pract \u003c/em\u003e2023, \u003cstrong\u003e73\u003c/strong\u003e:103830.\u003c/li\u003e\n\u003cli\u003eAlahdab F, Halvorsen AJ, Mandrekar JN, Vaa BE, Montori VM, West CP, Murad MH, Beckman TJ: \u003cstrong\u003eHow do we assess resilience and grit among internal medicine residents at the Mayo Clinic? A longitudinal validity study including correlations with medical knowledge, professionalism and clinical performance\u003c/strong\u003e. \u003cem\u003eBMJ Open \u003c/em\u003e2020, \u003cstrong\u003e10\u003c/strong\u003e(12):e040699.\u003c/li\u003e\n\u003cli\u003eRansdell L, Lane T, Schwartz A, Wayment H, Baldwin J: \u003cstrong\u003eMentoring New and Early-Stage Investigators and Underrepresented Minority Faculty for Research Success in Health-Related Fields: An Integrative Literature Review (2010\u0026ndash;2020)\u003c/strong\u003e. \u003cem\u003eInternational Journal of Environmental Research and Public Health \u003c/em\u003e2021, \u003cstrong\u003e18\u003c/strong\u003e(2):432.\u003c/li\u003e\n\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":false,"highlight":"","institution":"","isAcceptedByJournal":true,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"bmc-medical-education","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"meed","sideBox":"Learn more about [BMC Medical Education](http://bmcmededuc.biomedcentral.com/)","snPcode":"","submissionUrl":"https://www.editorialmanager.com/meed/default.aspx","title":"BMC Medical Education","twitterHandle":"BMC_series","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"em","reportingPortfolio":"BMC Series","inReviewEnabled":true,"inReviewRevisionsEnabled":true},"keywords":"Grit, depressive symptoms, depression, medical resident, longitudinal study","lastPublishedDoi":"10.21203/rs.3.rs-6631869/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-6631869/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003ch2\u003eBackground\u003c/h2\u003e \u003cp\u003eGrit, defined as perseverance and passion for long-term goals, played an essential role in academic success and resilience in the medical profession. Previous cross-sectional studies indicated an association between higher grit and lower depressive symptoms among medical residents. However, no longitudinal studies examined whether grit was associated with later depressive symptoms during residency training. This study explored the association between grit at the start of a job and depressive symptoms at the end of the first-year postgraduate (PGY1) residency among Japanese medical residents.\u003c/p\u003e\u003ch2\u003eMethods\u003c/h2\u003e \u003cp\u003eThis longitudinal study analyzed data from all first-year postgraduate residents at Tokyo Medical and Dental University in Tokyo, Japan, from 2021 to 2023. We administered surveys at the start of the first-year postgraduate residency and again at the end. We measured grit using the Japanese version of the Short Grit Scale (Grit-S) and assessed depressive symptoms with the Center for Epidemiologic Studies Depression Scale. We examined the association between grit at the baseline and depressive symptoms at the end of the first-year postgraduate residency using Poisson regression with robust error variance analysis.\u003c/p\u003e\u003ch2\u003eResults\u003c/h2\u003e \u003cp\u003eOf the 146 residents, 28 (19.2%) exhibited depressive symptoms at the end of first-year postgraduate residency. After adjusting for baseline depressive state, age, sex, graduated university, sleeping hours, and training program, a one-unit increase in Grit-S score was associated with a 42% lower risk of depressive symptoms at the end of the first-year postgraduate residency (relative risk [RR]: 0.58; 95% confidence interval [CI]: 0.37\u0026ndash;0.88). Furthermore, the Grit-S subscales, perseverance of effort and consistency of interest, were all associated with a lower risk of depressive symptoms (RR: 0.68; 95% CI: 0.48\u0026ndash;0.96, RR: 0.70; 95% CI: 0.49\u0026ndash;0.99, respectively).\u003c/p\u003e\u003ch2\u003eConclusion\u003c/h2\u003e \u003cp\u003eThis study demonstrated that higher grit at the start of residency was significantly associated with a lower risk of depressive symptoms among Japanese medical residents by the end of their first postgraduate year.\u003c/p\u003e","manuscriptTitle":"Association between Grit at the Start of Residency and Depressive Symptoms at the End of Residency Among Postgraduate Year 1 Medical Residents in Japan: A Longitudinal Study","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2025-05-28 12:37:58","doi":"10.21203/rs.3.rs-6631869/v1","editorialEvents":[{"type":"communityComments","content":0},{"type":"decision","content":"Revision requested","date":"2025-06-12T13:34:23+00:00","index":"","fulltext":""},{"type":"reviewerAgreed","content":"109567127602736187377108657912030071193","date":"2025-06-11T03:14:48+00:00","index":"hide","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2025-06-10T03:19:33+00:00","index":"hide","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2025-06-09T02:16:29+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"75308824759087590907875039585461410729","date":"2025-06-09T00:04:04+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"170251694179184244067492524775544702700","date":"2025-05-29T22:54:48+00:00","index":"hide","fulltext":""},{"type":"reviewersInvited","content":"","date":"2025-05-27T01:08:09+00:00","index":"","fulltext":""},{"type":"editorAssigned","content":"","date":"2025-05-23T06:23:02+00:00","index":"","fulltext":""},{"type":"checksComplete","content":"","date":"2025-05-22T12:41:09+00:00","index":"","fulltext":""},{"type":"submitted","content":"BMC Medical Education","date":"2025-05-22T12:40:05+00:00","index":"","fulltext":""}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"bmc-medical-education","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"meed","sideBox":"Learn more about [BMC Medical Education](http://bmcmededuc.biomedcentral.com/)","snPcode":"","submissionUrl":"https://www.editorialmanager.com/meed/default.aspx","title":"BMC Medical Education","twitterHandle":"BMC_series","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"em","reportingPortfolio":"BMC Series","inReviewEnabled":true,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"3f72e42e-b112-4380-ab87-031929a2b759","owner":[],"postedDate":"May 28th, 2025","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"published-in-journal","subjectAreas":[],"tags":[],"updatedAt":"2025-08-07T07:12:58+00:00","versionOfRecord":{"articleIdentity":"rs-6631869","link":"https://doi.org/10.1186/s12909-025-07651-4","journal":{"identity":"bmc-medical-education","isVorOnly":false,"title":"BMC Medical Education"},"publishedOn":"2025-07-19 16:05:15","publishedOnDateReadable":"July 19th, 2025"},"versionCreatedAt":"2025-05-28 12:37:58","video":"","vorDoi":"10.1186/s12909-025-07651-4","vorDoiUrl":"https://doi.org/10.1186/s12909-025-07651-4","workflowStages":[]},"version":"v1","identity":"rs-6631869","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-6631869","identity":"rs-6631869","version":["v1"]},"buildId":"XKTyCvWXoU3ODBz1xrDgd","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}