Novel patient-specific visual analogue survey (PVS) is validated in patients treated with collagenase injection for Dupuytren's disease

Objectives We developed and validated an electronically administered patient-specific visual analogue survey (PVS) to evaluate changes in hand function after treatment with injectable collagenase clostridium histolyticum (CCH) in Dupuytren's contracture. The items in the PVS were authored and ranked in importance by the patients. Methods In an open-label trial for patients with Dupuytren's contracture receiving CCH injection, 109 patients completed the PVS on the day of injection, day of manipulation and 30-day follow-up. For external validation, patients also completed standard patient-reported outcome measures, the Overall Treatment Effects Scale and QuickDASH, and underwent physician assessment of contracture via goniometry and the table top test. Results Responses were highly individualised with no single activity being chosen as important by more than 8% of patients. Sports-related activities were mentioned most often (23%). The PVS was highly responsive to changes in patients' conditions with CCH injection (effect size=1.49), much more so than the QuickDASH (effect size=0.50). Additionally, the PVS had no floor or ceiling effects, whereas the QuickDASH ceiling approached 20% post-injection. The PVS had excellent internal consistency (Cronbach's α=0.95) and correlated strongly with the QuickDASH post-injection (Spearman's=-0.67). PVS scores were significantly higher for patients reporting their condition had improved versus those reporting no change after injection. The test-retest reliability of the PVS was poor to fair, in part due to allowing patients to choose different activities at test and retest. However, test-retest reliability was good (intraclass correlation coefficient >0.7) and better than QuickDASH among patients who rated the same activities at test and retest. Conclusions The PVS is simple to administer and enables individualised assessment in a large number of patients. It is also readily adaptable for use in other diseases, particularly within musculoskeletal medicine. Level of evidence Therapeutic II: Prospective cohort.