Judgment skills, a missing component in health literacy: development of a tool for asthma patients in the Italian-speaking region of Switzerland

BACKGROUND Health literacy has been recognized as an important factor influencing health behaviors and health outcomes. However, its definition is still evolving, and the tools available for its measurement are limited in scope. Based on the conceptualization of health literacy within the Health Empowerment Model, the present study developed and validated a tool to assess patient's health knowledge use, within the context of asthma self-management. METHODS A review of scientific literature on asthma self-management, and several interviews with pulmonologists and asthma patients were conducted. From these, 19 scenarios with 4 response options each were drafted and assembled in a scenario-based questionnaire. Furthermore, a three round Delphi procedure was carried out, to validate the tool with the participation of 12 specialists in lung diseases. RESULTS The face and content validity of the tool were achieved by face-to-face interviews with 2 pulmonologists and 5 patients. Consensus among the specialists on the adequacy of the response options was achieved after the three round Delphi procedure. The final tool has a 0.97 intra-class correlation coefficient (ICC), indicating a strong level of agreement among experts on the ratings of the response options. The ICC for single scenarios, range from 0.92 to 0.99. CONCLUSIONS The newly developed tool provides a final score representing patient's health knowledge use, based on the specialist's consensus. This tool contributes to enriching the measurement of a more advanced health literacy dimension.