Interpretability of the European Heart Failure Self-care Behaviour scale

Kim P Wagenaar,1 Berna DL Broekhuizen,1 Frans H Rutten,1 Anna Strömberg,2 Henk F van Stel,1 Arno W Hoes,1 Tiny Jaarsma2 1Julius Center for Health Sciences and Primary Care, University Medical Centre Utrecht, Utrecht, the Netherlands; 2Department of Social and Welfare Studies, Linköping University, Linköping, Sweden Objective: The European Heart Failure Self-care Behaviour scale (EHFScBs) is a valid patient-reported questionnaire to measure self-care behavior of heart failure (HF) patients. We assessed the interpretability of the EHFScBs.Methods: We used data of 1,023 HF patients. Interpretability refers to the clinical meaning of the score and its changes over time. We operationalized interpretability by evaluating distributions of EHFScBs scores across relevant HF subgroups by eyeballing, by testing the risk on hospitalizations and mortality of a plausible threshold, and by determining a clinically relevant minimal important change (MIC). The scale score ranged from 0 to 100, with a higher score meaning better self-care. A threshold of ≥70 was defined as adequate and <70 as inadequate self-care.Results: The EHFScBs scores were similarly normally distributed among the subgroups with a mean between 57.8 (SD 19.4) and 72.0 (SD 18.0). The 464 HF patients with adequate self-care had significantly less all-cause hospitalizations than the 559 patients with inadequate self-care.Conclusion: The degree of self-care showed to be independent of relevant HF subgroups. A single threshold of 70 accurately discriminated between patients with adequate and inadequate self-care.Practice implications: The threshold of 70 can be used in designing studies and informing health policy makers. Keywords: heart failure, self-care, interpretability, patient-reported outcome, threshold and minimal important chang