RESUMO
BACKGROUND: Patients provide a unique, irreplaceable, and essential perspective in evaluating patient safety. The suite of Patient Reported Experiences and Outcomes of Safety in Primary Care (PREOS-PC) tools are a notable exception to the scarcity of patient-reported patient safety measures. Full evaluation of their performance has only been attempted for the English version, thereby limiting its international applicability. OBJECTIVES: To assess the psychometric performance of the Spanish and Catalan versions of the PREOS-PC-Compact. METHODS: Cross-sectional validation study. We used Classical Test Theory methods to examine scale score distribution, internal consistency, and construct validity; and Item Response Theory (IRT) methods to further explore construct validity. RESULTS: 3287 patients completed the Spanish version, and 1007 the Catalan version. Similar results were obtained for both versions. Confirmatory Factor Analysis supported a single construct for each scale. The correlations between PREOS-PC-Compact scales and known group analysis suggested adequate construct validity (inconclusive for known groups at the provider level). All four multi-item scales demonstrated adequate internal consistency reliability (α > 0.7), which was only confirmed for test-retest reliability for 'Practice activation.' A sample between 60-90 patients per practice was estimated sufficient to produce scores with reliability > 0.7 for all scales except for harm scales. IRT models showed disordered thresholds for 'Practice activation' and 'Harm burden' but showed excellent fit after reducing the response categories. CONCLUSION: The Spanish and Catalan versions of the PREOS-PC-Compact are broadly valid and reliable tools to measure patient safety in Spanish primary care centres; confirmation of lower-than-expected test-rest reliability merits further examination .