The validity of self-rating depression scales in patients with chronic widespread pain: a Rasch analysis of the Major Depression Inventory

Abstract

From the perspective of the Rasch measurement model, the MDI demonstrated insufficient psychometric properties when used to identify and quantify severity of depression in a clinical sample of females with CWP. The observed item endorsement pattern indicated that, in this study population, the relatively high depression severity scores primarily pertained to a common core of pain-related somatic symptoms. Careful consideration when interpreting questionnaire-derived scores of depression implemented in research and routine clinical care of patients with chronic pain is warranted.