Development of short form questionnaires for the assessment of work capacity in cardiovascular rehabilitation patients.

OBJECTIVES Prevention of job loss is an essential objective of cardiovascular rehabilitation. However, comprehensive and economic diagnostic instruments on work limitations are missing. The present study describes development of short form questionnaires from 2 domains of the WCIB-Cardio item banks for the assessment of work capacity in cardiovascular rehabilitation patients. MATERIALS AND METHODS 283 cardiovascular rehabilitation patients were recruited from 14 German rehabilitation clinics. Based on the WCIB-Cardio with the domains of cognitive and physical work capacity, we developed a short form for both domains. Item selection criteria were content coverage, content appropriateness, internal consistency reliability (≥ 0.8). We used correlation of person location scores of the short forms with person location scores of the full item banks to examine the extent of measurement precision. RESULTS For each domain of the WCIB-Cardio a short form was developed (cognitive work capacity - 14 items; physical work capacity 7 - items). In both domains psychometric properties were good (person separation index: cognitive work capacity - 0.80; physical work capacity - 0.80). Correlation meaures of the short form with the full item banks showed a high accordance of person locations for both domains (cognitive work capacity: r = 0.97; physical work capacity: r = 0.95). CONCLUSIONS The calibrated instrument WCIB-Cardio provides the possibility to develop short form questionnaires with high psychometric quality. These short forms make it possible to monitor patient's work capacity in cardiovascular rehabilitation settings in a more economical way.