Patients' interpretations of individual PROMIS-10 Global Health items: a cognitive interview study in high-impact...

The purpose of this study was to explore the content validity of the Danish version of the PROMIS-10 Global Health questionnaire in patients with high-impact chronic pain by (1) identifying problematic items and reasons for misunderstandings between participants' interpretations and the intended meaning, and (2) exploring how participants understand and interpret the items.

Individual cognitive interviews were conducted with participants with high-impact chronic pain referred to two Danish Pain Centers using a structured step-by-step interview approach. The first objective was analyzed mainly using a deductive structured approach, while the second objective was analyzed mainly using an inductive thematic approach focusing on participants' perspectives.

Participants (n = 19) generally understood the items as intended but showed 21% and 11% non-congruency for items 8r (fatigue) and 7r (pain intensity), as they responded based on a longer timeframe than "the past 7 days". Overall, participants interpreted the items through a physical, psychological and social perspective. Further, items 5 (social activities and relationships) and 6 (daily physical activities) were perceived to overlap thematically with item 9r (social activities and roles). Additionally, the provided examples in items 5 and 6 influenced responses, and some deemed item 7r irrelevant, as it did not reflect their pain experiences.

The findings contribute to the validation of PROMIS-10 Global Health in patients with high-impact chronic pain by providing insights into how participants understand and interpret the items, highlighting areas for minor refinement. Further qualitative research on the validity of PROMIS-10 Global Health in this population is needed.