The Effectiveness of the Incredible Years Program for Children with ADHD: A Meta-Analysis

The Effectiveness of the Incredible Years Program for Children with ADHD: A Meta-Analysis | 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 The Effectiveness of the Incredible Years Program for Children with ADHD: A Meta-Analysis Gökhan KAYILI, KEVSER KILIÇ, EMRE DEMİRTAŞ, MELİKE DURDANE GÜRBÜZ ÜNALMIŞ, and 1 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-8427975/v1 This work is licensed under a CC BY 4.0 License Status: Under Review Version 1 posted 7 You are reading this latest preprint version Abstract Purpose : The Incredible Years (IY) Program is an umbrella framework that includes various early intervention programs designed for different target groups. Implemented in 36 states across the United States since 1984, the program has also been applied to children who have been diagnosed with Attention-Deficit/Hyperactivity Disorder (ADHD). Method : Using the meta-analysis technique, the effect size of the Incredible Years (IY) Program was calculated based on overall and moderator variables. Searches were conducted in six different databases, and experimental studies published between 2000 and 2024 that implemented the program with children diagnosed with ADHD were included. The studies were examined for publication bias and heterogeneity, and effect sizes were computed through fixed-effect model and random-effects model. Results : The meta-analysis included 18 studies. Most of these studies were published articles, involved children aged 4–6, and implemented a 20-week intervention period. The included studies were significant under both fixed-effect model and random-effects model. The fixed-effect model yielded a weak effect size with a point estimate of 0.169, while the random-effects model revealed a small effect size with a point estimate of 0.383. The analysis revealed a high and statistically significant level of heterogeneity. Results from multiple publication bias tests suggested no evidence of publication bias. Intervention duration and year of publication were not found to have an effect in the analyses of effect size, whereas age groups, measurement instruments, and type of publication showed an effect. Conclusion : The analysis demonstrated that the Incredible Years (IY) Program proves to be effective for children diagnosed with ADHD. Accordingly, the use of the program with children diagnosed with ADHD is recommended. Implications for Rehabilitation : Considering the limited yet positive impacts of the IY Program on children with ADHD, its implementation could be expanded by providing training to staff working in rehabilitation centers. Furthermore, the program may serve as a supplementary intervention for children who have developmental disabilities receiving education or therapy, thereby offering additional support for their development. Full Text Additional Declarations No competing interests reported. Supplementary Files prisma.pdf prisma2.pdf Cite Share Download PDF Status: Under Review Version 1 posted Reviews received at journal 29 Apr, 2026 Reviewers agreed at journal 23 Apr, 2026 Reviewers invited by journal 22 Jan, 2026 Editor assigned by journal 22 Jan, 2026 Editor invited by journal 19 Jan, 2026 Submission checks completed at journal 15 Jan, 2026 First submitted to journal 15 Jan, 2026 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. We do this by developing innovative software and high quality services for the global research community. Our growing team is made up of researchers and industry professionals working together to solve the most critical problems facing scientific publishing. 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-8427975","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":578855106,"identity":"1acaf49a-7c97-4651-9a0b-792632b5aea2","order_by":0,"name":"Gökhan KAYILI","email":"","orcid":"","institution":"Selçuk University","correspondingAuthor":false,"prefix":"","firstName":"Gökhan","middleName":"","lastName":"KAYILI","suffix":""},{"id":578855107,"identity":"d6d433e2-2d34-4a1d-a88c-bef3fa6933da","order_by":1,"name":"KEVSER KILIÇ","email":"","orcid":"","institution":"Selçuk University","correspondingAuthor":false,"prefix":"","firstName":"KEVSER","middleName":"","lastName":"KILIÇ","suffix":""},{"id":578855108,"identity":"62182b37-0905-44d1-ad8c-58bd056083f1","order_by":2,"name":"EMRE DEMİRTAŞ","email":"","orcid":"","institution":"Selçuk University","correspondingAuthor":false,"prefix":"","firstName":"EMRE","middleName":"","lastName":"DEMİRTAŞ","suffix":""},{"id":578855109,"identity":"6d882ba5-a42c-435e-9b94-ce5ce3be1ca5","order_by":3,"name":"MELİKE DURDANE GÜRBÜZ ÜNALMIŞ","email":"data:image/png;base64,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","orcid":"","institution":"Selçuk University","correspondingAuthor":true,"prefix":"","firstName":"MELİKE","middleName":"DURDANE GÜRBÜZ","lastName":"ÜNALMIŞ","suffix":""},{"id":578855110,"identity":"7dca5399-9d1a-4d20-88d2-664507709838","order_by":4,"name":"Murat ÖZPOLAT","email":"","orcid":"","institution":"Selçuk University","correspondingAuthor":false,"prefix":"","firstName":"Murat","middleName":"","lastName":"ÖZPOLAT","suffix":""}],"badges":[],"createdAt":"2025-12-22 19:23:23","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-8427975/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-8427975/v1","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":101254309,"identity":"dd20b29a-b527-42aa-adad-a467487300b4","added_by":"auto","created_at":"2026-01-27 18:25:27","extension":"pdf","order_by":1,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":853194,"visible":true,"origin":"","legend":"","description":"","filename":"METAANALYSISSTUDY.pdf","url":"https://assets-eu.researchsquare.com/files/rs-8427975/v1_covered_4129e11d-2645-46b3-8a95-5c46efd68314.pdf"},{"id":101254307,"identity":"ad78e55b-7c7d-4a07-9aeb-d1b54e222b73","added_by":"auto","created_at":"2026-01-27 18:25:21","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"supplement","size":14592,"visible":true,"origin":"","legend":"","description":"","filename":"prisma.pdf","url":"https://assets-eu.researchsquare.com/files/rs-8427975/v1/73da9898249f8cbd07c4bd0a.pdf"},{"id":101254302,"identity":"7d12f48b-f577-42a2-85d8-b3084b7c8c4c","added_by":"auto","created_at":"2026-01-27 18:25:18","extension":"pdf","order_by":1,"title":"","display":"","copyAsset":false,"role":"supplement","size":13862,"visible":true,"origin":"","legend":"","description":"","filename":"prisma2.pdf","url":"https://assets-eu.researchsquare.com/files/rs-8427975/v1/22415e9c487305fd28719e86.pdf"}],"financialInterests":"No competing interests reported.","formattedTitle":"\u003cp\u003e\u003cstrong\u003eThe Effectiveness of the Incredible Years Program for Children with ADHD: A Meta-Analysis\u003c/strong\u003e\u003c/p\u003e","fulltext":[],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":false,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":false,"highlight":"","institution":"","isAcceptedByJournal":false,"isAuthorSuppliedPdf":true,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":true,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"bmc-psychology","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"psyo","sideBox":"Learn more about [BMC Psychology](http://bmcpsychology.biomedcentral.com/)","snPcode":"","submissionUrl":"","title":"BMC Psychology","twitterHandle":"BMC_series","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"stoa","reportingPortfolio":"BMC Series","inReviewEnabled":true,"inReviewRevisionsEnabled":true},"keywords":"","lastPublishedDoi":"10.21203/rs.3.rs-8427975/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-8427975/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003e\u003cem\u003e\u003cstrong\u003ePurpose\u003c/strong\u003e\u003c/em\u003e\u003cstrong\u003e:\u003c/strong\u003e The Incredible Years (IY) Program is an umbrella framework that includes various early intervention programs designed for different target groups. Implemented in 36 states across the United States since 1984, the program has also been applied to children who have been diagnosed with Attention-Deficit/Hyperactivity Disorder (ADHD).\u003c/p\u003e\n\u003cp\u003e\u003cem\u003e\u003cstrong\u003eMethod\u003c/strong\u003e\u003c/em\u003e\u003cstrong\u003e:\u003c/strong\u003e Using the meta-analysis technique, the effect size of the Incredible Years (IY) Program was calculated based on overall and moderator variables. Searches were conducted in six different databases, and experimental studies published between 2000 and 2024 that implemented the program with children diagnosed with ADHD were included. The studies were examined for publication bias and heterogeneity, and effect sizes were computed through fixed-effect model and random-effects model.\u003c/p\u003e\n\u003cp\u003e\u003cem\u003e\u003cstrong\u003eResults\u003c/strong\u003e\u003c/em\u003e\u003cstrong\u003e:\u003c/strong\u003e The meta-analysis included 18 studies. Most of these studies were published articles, involved children aged 4–6, and implemented a 20-week intervention period. The included studies were significant under both fixed-effect model and random-effects model. The fixed-effect model yielded a weak effect size with a point estimate of 0.169, while the random-effects model revealed a small effect size with a point estimate of 0.383. The analysis revealed a high and statistically significant level of heterogeneity. Results from multiple publication bias tests suggested no evidence of publication bias. Intervention duration and year of publication were not found to have an effect in the analyses of effect size, whereas age groups, measurement instruments, and type of publication showed an effect.\u003c/p\u003e\n\u003cp\u003e\u003cem\u003e\u003cstrong\u003eConclusion\u003c/strong\u003e\u003c/em\u003e\u003cstrong\u003e: \u003c/strong\u003eThe analysis demonstrated that the Incredible Years (IY) Program proves to be effective for children diagnosed with ADHD. Accordingly, the use of the program with children diagnosed with ADHD is recommended.\u003c/p\u003e\n\u003cp\u003e\u003cem\u003e\u003cstrong\u003eImplications for Rehabilitation\u003c/strong\u003e\u003c/em\u003e\u003cstrong\u003e: \u003c/strong\u003eConsidering the limited yet positive impacts of the IY Program on children with ADHD, its implementation could be expanded by providing training to staff working in rehabilitation centers. Furthermore, the program may serve as a supplementary intervention for children who have developmental disabilities receiving education or therapy, thereby offering additional support for their development.\u003c/p\u003e","manuscriptTitle":"The Effectiveness of the Incredible Years Program for Children with ADHD: A Meta-Analysis","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2026-01-27 18:24:42","doi":"10.21203/rs.3.rs-8427975/v1","editorialEvents":[{"type":"communityComments","content":0},{"type":"editorInvitedReview","content":"","date":"2026-04-29T20:41:14+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"246582896756977345811288720432469349435","date":"2026-04-23T13:27:34+00:00","index":"hide","fulltext":""},{"type":"reviewersInvited","content":"","date":"2026-01-22T11:41:58+00:00","index":"","fulltext":""},{"type":"editorAssigned","content":"","date":"2026-01-22T11:16:37+00:00","index":"","fulltext":""},{"type":"editorInvited","content":"","date":"2026-01-19T08:15:49+00:00","index":"","fulltext":""},{"type":"checksComplete","content":"","date":"2026-01-15T14:00:25+00:00","index":"","fulltext":""},{"type":"submitted","content":"BMC Psychology","date":"2026-01-15T13:53:12+00:00","index":"","fulltext":""}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"bmc-psychology","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"psyo","sideBox":"Learn more about [BMC Psychology](http://bmcpsychology.biomedcentral.com/)","snPcode":"","submissionUrl":"","title":"BMC Psychology","twitterHandle":"BMC_series","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"stoa","reportingPortfolio":"BMC Series","inReviewEnabled":true,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"b721bb42-75b8-4463-961b-759174b4d4ac","owner":[],"postedDate":"January 27th, 2026","published":true,"recentEditorialEvents":[{"type":"editorInvitedReview","content":"","date":"2026-04-29T20:41:14+00:00","index":87,"fulltext":""}],"rejectedJournal":[],"revision":"","amendment":"","status":"under-review","subjectAreas":[],"tags":[],"updatedAt":"2026-01-27T18:24:42+00:00","versionOfRecord":[],"versionCreatedAt":"2026-01-27 18:24:42","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-8427975","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-8427975","identity":"rs-8427975","version":["v1"]},"buildId":"XKTyCvWXoU3ODBz1xrDgd","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}