Development and psychometric validity of the Perioperative Anxiety Scale-7 (PAS-7)

Abstract Background Preoperative anxiety is a common psychological reaction in perioperative patients. The absence of a valid measurement tool of it hinders the evaluation of interventions to treat preoperative anxiety in China. This study aims to develop the Perioperative Anxiety Scale-7 (PAS-7) and to test its reliability, validity and cut-off value. Methods A total of 280 patients over 16 years old who were undergoing elective surgery were recruited to complete the PAS-7 and the Generalized Anxiety Disorder-7 scale (GAD-7) one day before surgery. Results The PAS-7 included 7 items, which were divided into two dimensions: mental anxiety and somatic anxiety. These two dimensions could explain 74.294% of the population variance. The internal consistency of each dimension ranged from 0.761–0.933. The confirmatory factor analysis showed that the model fit of the scale was good (χ2= 34.798, df = 13, χ2/df = 2.677, CFI = 0.949, GFI = 0.924, RMSEA = 0.115). The correlations between the GAD-7 and each dimension and the total score of the scale were significant. A cut-off score of 8, maximizing the Youden Index, yielded a sensitivity of 75% and a specificity of 84.6% (95% CI: 0.88–0.97). Conclusions The PAS-7 had good reliability and validity and could be used as an effective tool to evaluate preoperative anxiety.