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 measures 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

Development and validation of parallel short forms PaSA-cardio for the assessment of general anxiety in cardiovascular rehabilitation patients using Rasch analysis

Objective: To develop and validate parallel short forms for the assessment of general anxiety in cardiovascular rehabilitation patients, that facilitate repeated measurement over time without contamination from residual practice effect variance.Design: Development of the parallel short forms using Rasch analysis. Validation study.Setting: Cardiac rehabilitation centres in Germany.Subjects: Cardiovascular rehabilitation patients.Interventions: Not applicable.Main measures: Parallel short forms PaSA-cardio, Hospital Anxiety and Depression Scale, Short Form Health Survey SF-12 and Structured Clinical Interview for DSM-IV Axis I Disorders.Results: Each version of the parallel short forms (PaSA-cardio-I and PaSA-cardio-II) comprises ten items. The two forms fitted to the Rasch model with a non-significant item–trait interaction (PaSA-cardio-I: chi-square = 39.49, degrees of freedom = 30, probability = 0.12; PaSA-cardio-II: chi-square = 26.56, degrees of freedom = 30, probability = 0.65). Person-separation reliability was 0.75/0.76. Unidimensionality could be verified. Correlation between the two models was 0.94 and 0.95, and correlations with the underlying item bank were 0.95 and 0.93. Validity could be confirmed. The area under the curve was between 0.88 and 0.97 for PaSA-cardio-I and between 0.92 and 0.95 for PaSA-cardio-II.Conclusions: Assessment of general anxiety in cardiovascular rehabilitation patients with the PaSA-cardio was valid, economical and accurate. The two forms of the PaSA-cardio are equivalent and allow retest without contamination from residual practice effect variance