Development And Psychometric Testing Of A Patient-Reported Experience Measures (PREMs) Core Set To Assess Patient-Centeredness (PC)

Abstract

Patient-centeredness is increasingly recognized as a key indicator of healthcare quality. To improve patient-centeredness effectively, psychometrically sound measurement of its degree is essential. Patient-reported experience measures (PREMs) are particularly suited to capture the quality of care from the patient’s perspective. However, a generic PREM that comprehensively assesses patient-centeredness is still lacking. This dissertation addresses this gap through five publications pursuing two aims: (1) to develop a generic German-language PREM comprehensively assessing patient-centeredness - the Experienced Patient-Centeredness Questionnaire (EPAT) - and (2) to select items for both modular and short versions of the EPAT and evaluate their psychometric properties.

Publication 1 is a study protocol outlining the study design that provided the framework for this dissertation and guided the investigation of all research questions.

Publication 2 addresses the definition of the construct patient-centeredness from the patients’ perspective. In a Delphi study with n = 226 patients, all 15 dimensions of the integrative model of patient-centeredness were rated as highly relevant, and a sixteenth dimension, “patient safety,” was added.

Publication 3 details the item development process based on a literature review including 48 PREMs, six focus groups with n = 40 patients, and n = 10 expert interviews. Relevance and comprehensiveness were ensured through a relevance rating with 32 experts, and comprehensibility was confirmed in 34 cognitive interviews with patients. Collectively, these steps demonstrated the content validity of the developed items.

Publication 4 describes a cross-sectional study evaluating the psychometric properties of the EPAT in a sample of n = 2,024 patients. Item characteristics and content considerations were used to derive the EPAT-64 - a modular version assessing all 16 dimensions of patient-centeredness with four items each. For the final version, structural validity, construct validity, and reliability were evaluated, demonstrating robust psychometric properties, although some items exhibited ceiling effects and high “does not concern me” response rates.

Publication 5 describes how the same dataset was used to select items for the EPAT-16, a short version with one item representing each of the 16 dimensions. It demonstrated good construct validity and reliability, with some limitations in structural validity and measurement invariance.

In summary, this dissertation presents the first comprehensive and generic PREM for assessing patient-centeredness and provides a best-practice example of questionnaire development that integrates theory-driven and data-driven methods to prioritize content validity throughout the entire process. The EPAT’s modular and short forms offer flexible tools for both research and routine healthcare, supporting quality monitoring, intervention evaluation, and public reporting. Future research should further examine its responsiveness, test measurement invariance across diverse populations, and explore strategies for effective implementation in clinical practice.