Development and evaluation of the measurement properties of a generic questionnaire measuring patient perceptions of person-centred care

Background Implementation of person-centred care (PCC) is a challenging undertaking. Thus, a call has been issued for a robust and generic instrument to measure and enable evaluation of PCC across settings and patient groups. This study aimed to develop a generic questionnaire measuring patients' perceptions of PCC. Further aims were to evaluate its content and measurement properties using a mixed-methods approach entailing Rasch and qualitative content analyses. Methods The study was conducted in three iterative phases. Phase one included six key informants to gain a broad view of the concept. Phase two entailed a Delphi study involving two rounds with eight experts who generated ratings on relevance, readability, comprehensiveness and suggestions for revision. Data were analysed using the Item Content Validity Index in conjunction with qualitative comments to improve the questionnaire. Phase three was performed using a mixed-methods design. Quantitative data were collected from patients (n = 553) responding to the questionnaire who were recruited from six in- and outpatient care units in a health care region in Sweden. Data was analysed using the Rasch measurement model. Qualitative data were based on the respondents' free-text comments, cognitive interviews (n = 10) and field notes, and then analysed with deductive content analysis. Results A questionnaire was developed and operationalised based on the information given by key informants in phase one and then validated for its content by experts in phase two. In phase three Rasch analyses revealed problems with targeting, thresholds and two misfitting items. These problems were corroborated by data from the qualitative analyses, which also revealed some issues of wording and interpretation of items. When thresholds were resolved and two items removed, the questionnaire met the assumptions of the Rasch model. Conclusions Experts gave the questionnaire content high ratings and it met measurement requirements assumed by the Rasch model after revisions. Those problems on targeting that remain need to be addressed in future studies. Meanwhile, we regard the questionnaire as of sufficient quality to be useful in benchmarking PCC.