Translating patient reported outcome measures: methodological issues explored using cognitive interviewing with three rheumatoid arthritis measures in six European languages.

Objective: Cross-cultural translation of patient-reported outcome measures (PROMs) is a lengthy process, often performed professionally. Cognitive interviewing assesses patient comprehension of PROMs. The objective was to evaluate the usefulness of cognitive interviewing to assess translations and compare professional (full) with non-professional (simplified) translation processes.