Through the patients' eyes: psychometric evaluation of the 64-item version of the Experienced Patient-Centeredness Questionnaire (EPAT-64).

Background: Patient-reported experience measures (PREMs) are valuable tools to evaluate patient-centredness (PC) from the patients' perspective. Despite their utility, a comprehensive PREM addressing PC has been lacking. To bridge this gap, we developed the preliminary version of the Experienced Patient-Centeredness Questionnaire (EPAT), a disease-generic tool based on the integrative model of PC comprising 16 dimensions. It demonstrated content validity. This study aimed to test its psychometric properties and to develop a final 64-item version (EPAT-64).

Methods: In this cross-sectional study, we included adult patients treated for cardiovascular diseases, cancer, musculoskeletal diseases and mental disorders in inpatient or outpatient settings in Germany. For each dimension of PC, we selected four items based on item characteristics such as item difficulty and corrected item-total correlation. We tested structural validity using confirmatory factor analysis, examined reliability by McDonald's Omega and tested construct validity by examining correlations with general health status and satisfaction with care.

Results: Analysis of data from 2.024 patients showed excellent acceptance and acceptable item-total correlations for all EPAT-64 items, with few items demonstrating ceiling effects. The confirmatory factor analysis indicated the best fit for a bifactor model, where each item loaded on both a general factor and a dimension-specific factor. Omega showed high reliability for the general factor, while varying for specific dimensions. Construct validity was confirmed by absence of strong correlations with general health status and a strong correlation of the general factor with satisfaction with care.

Conclusions: EPAT-64 demonstrated commendable psychometric properties. This tool allows comprehensive assessment of PC, offering flexibility to users who can measure each dimension with a four-item module or choose modules based on their needs. EPAT-64 serves multiple purposes, including quality improvement and evaluation of interventions aiming to enhance PC. Its versatility empowers users in diverse healthcare settings.