A practice test and selection of a core set of outcome-based quality indicators in Dutch primary care physical therapy for patients with COPD: a cohort study

AIM: To estimate the comparability and discriminability of outcome-based quality indicators by performing a practice test in Dutch physical therapy primary care, and to select a core set of outcome-based quality indicators that are well accepted by physical therapists based on their perceived added value as a quality improvement tool. METHODS: First, a list of potential quality indicators was defined, followed by determination of the comparability (case-mix adjusted multilevel analysis) and discriminability (intraclass correlation coefficient (ICC)). Second, focus group meetings were conducted with stakeholders (physical therapists and senior researchers) to select a core set of quality indicators. RESULTS: Overall, 229 physical therapists from 137 practices provided 2651 treatment episodes. Comparability: in 10 of the 11 case-mix adjusted models, the ICC increased compared with the intercept-only model. Discriminability: the ICC ranged between 0.01 and 0.34, with five of the 11 ICCs being >0.10. The majority of physical therapists in each focus group preferred the inclusion of seven quality indicators in the core set, including three process and four outcome indicators based upon the 6-min walk test (6MWT), the Clinical COPD Questionnaire (CCQ), and the determination of quadriceps strength using a hand-held dynamometer. CONCLUSION: This is the first study to describe the comparability and discriminability of the outcome-based quality indicators selected for patients with COPD treated in primary care physical therapy practices. Future research should focus on increasing data collection in daily practice and on the development of tangible methods to use as the core set of a quality improvement tool.