Construct validity of the Dutch version of the 12-item Partners in Health scale : measuring self-management behaviour and knowledge in COPD patients

The 12-item Partner in Health (PIH) scale was developed in Australia to measure self-management behaviour and knowledge in patients with chronic diseases. The scale has undergone several changes since first published. Our study aim was to validate the latest PIH in Dutch COPD patients.The 12 items of the PIH are scored on a self-rated 9-point Likert scale (range: 0-8; higher scores indicate better self-management), providing total and subscale scores (knowledge, coping, recognition and management of functions, adherence to treatment).We used forward-backward translation of the latest version of the Australian PIH. Dimensionality and reliability analyses were performed to investigate the psychometric properties, and to determine whether the Dutch PIH replicated the same four subscales of self-management as the original PIH.Reanalysis of the original PIH validation study (186 Australian patients with chronic diseases) showed a single scale. Two scales (1. knowledge and coping; 2. recognition and management of symptoms, adherence to treatment) were found for the Dutch PIH (118 Dutch COPD patients). The correlation between the two Dutch scales was 0.43. The lower-bound of the reliability of the total scale was 0.81 (Australian PIH) and 0.84 (Dutch PIH).Different scale structures were found for the original Australian and the Dutch PIH. Our results did not support the 4-scale structure reported previously. To increase comparability and generalisability of our findings, the scale structure of the revised Australian PIH needs to be investigated further. Meanwhile, we advise using the PIH total score or two subscale scores when assessing COPD patients.