Development and validation of the patient evaluation scale (PES) for primary health care in Nigeria

Background: Questionnaires developed for patient evaluation of the quality of primary care are often focused on primary care systems in developed countries.
Aim: To report the development and validation of the patient evaluation scale (PES) designed for use in the Nigerian primary health care context.
Methods: An iterative process was used to develop and validate the questionnaire using patients attending 28 primary health centres across 8 states in Nigeria. The development involved literature review, patient interviews, expert reviews, cognitive testing with patients and waves of quantitative cross-sectional surveys. The questionnaire’s content validity, internal structures, acceptability, reliability and construct validity are reported.

Findings: The full and shortened version of PES with 27 and 18-items respectively were developed through these process. The low item non-response from the serial cross-sectional surveys depicts questionnaire’s acceptability among the local population. PES-SF has Cronbach’s alpha of 0.87 and three domains (code-named ‘facility’, ‘organisation’, and ‘healthcare’) with Cronbach’s alphas of 0.78, 0.79 and 0.81 respectively. Items in the multi-dimensional questionnaire demonstrated adequate convergent and discriminant properties. PES-SF scores show significant positive correlation with scores of the full PES and also discriminated population groups in support of a priori hypotheses.

Conclusion: The PES and PES-SF contain items that are relevant to the needs of patients in Nigeria. The good measurement properties of the questionnaire demonstrates its potential usefulness for patient-focused quality improvement activities in Nigeria. There is still need to translate these questionnaires into major languages in Nigeria and assess their validity against external quality criteria.