A COSMIN-based content validity study of PROMIS GH-10 German version in Switzerland

Abstract Background A COSMIN systematic review of generic patient-reported outcome measures in Switzerland indicated a limited number of content validity studies. Due to clinicians’ efforts to reduce response burden, several short forms are available, but remain understudied vis-à-vis content validity. The current study utilized the COSMIN framework to examine the PROMIS Scale v1.2 – Global Health (PROMIS-GH) German version. Methodology This mixed-methods study utilized semi-structured interviews with n = 8 professionals and n = 16 patients to examine the PROMIS GH-10’s relevance, comprehensiveness, and comprehensibility. Ordinal ratings on 3-point Likert-type scales were examined in conjunction with free-response probes and open feedback. Results From the patient perspective, the German version of the PROMIS-GH demonstrated mixed evidence for content validity. While patients generally found the instrument easy to understand, they found it partially irrelevant due to three items (Global10r, Global08r, and Global07r) and incomplete due to missing domains. On the other side from the healthcare professionals, the instrument is well-received with sufficient content validity. Conclusion This is the first study to examine the content validity of the PROMIS GH-10 for potential use in Switzerland. Although conducted in Switzerland’s majority-German-speaking region, further studies should be conducted in French- and Italian-speaking regions.