Measuring Patient Safety in Primary Care: The development and validation of the “Patient Reported Experiences and Outcomes of Safety in Primary Care” (PREOS-PC)
Ricci Cabello I., Avery AJ., Reeves D., Kadam U., Valderas JM.
ABSTRACT Purpose: To develop and validate a patient reported instrument for the measurement of patient safety related experiences and outcomes in Primary Care. Method: The instrument was developed in a multistage process supported by an international expert panel and informed by a systematic review of instruments, a meta-synthesis of qualitative studies, four patient focus groups, 18 cognitive interviews and a pilot study. The trial version of Patient Reported Experiences and Outcomes of Safety in Primary Care (PREOS-PC) covered five domains (11 scales): practice activation (1); patient activation (1); experiences of patient safety (1); harm (6); and general perceptions of patient safety (2). The questionnaire was posted to 6,736 patients in 45 practices across England. We used “gold standard” psychometric methods to evaluate its acceptability, reliability, structural and construct validity, and ability to discriminate among practices. Results: 1,244 (18.4%) completed questionnaires were returned. Median item-specific response rate was 91.3% (interquartile range 28.0%). No major ceiling/floor effects were observed. All six multi-item scales showed high internal consistency (Cronbach's α 0.75-0.96). Factor analysis, correlation between scales, and known group analyses generally supported structural and construct validity. The scales demonstrated a heterogeneous ability to discriminate between practices. The final version of PREOS-PC consisted in five domains, eight scales and 58 items. Conclusions: PREOS-PC is a new multi-dimensional patient safety instrument for primary care developed with experts and patients. Initial testing shows its potential for use in primary care and future developments will further address its use in actual clinical practice.