Background: The Ruminative Response Scale (RRS)-short form is one of the most widely used measures of rumination, comprising ten items and two components: reflection and brooding. The aim of this study was to investigate RRS validity and reliability in a clinical sample of French patients with major depressive disorder (MDD).
Subjects and methods: Outpatients with a DSM-IV-TR diagnosis of MDD were recruited from a public academic hospital in France. Depressive symptoms were evaluated by the Beck Depression Inventory, anxiety by the State-Trait Anxiety Inventory - state scale, and quality of life by the 36-Item Short Form Health Survey (SF-36) questionnaire. Confirmatory factor analyses, item-dimension correlations, Cronbach's α-coefficients, Rasch statistics, and external validity were tested. Differential item functioning analyses were performed for sex.
Results: A total of 109 patients participated. The final reflection-brooding two-factor model of the RRS showed a good fit (root-mean-square error of approximation 0.041, comparative fit index 0.987, standardized root-mean-square residual 0.048) after removing one item (daily diary writing). Internal item consistency and reliability were satisfactory for the two dimensions. External validity testing confirmed that RRS scores were correlated with Beck Depression Inventory, State-Trait Anxiety Inventory, and SF-36 scores. There was no differential item functioning across sexes.
Conclusion: These results demonstrated good scale reliability and validity for assessing rumination in patients with MDD.
Keywords: major depressive disorder; psychometric properties; reliability; response-style theory; rumination; validity.