Defining quality categories for evaluation of the doctor-patient relationship assessed through the patient-doctor relationship questionnaire (PDRQ-9)

Background The quality of the doctor-patient relationship plays a crucial role in patients' experiences with healthcare services, positively influencing clinical outcomes and satisfaction with care. The Patient-Doctor Relationship Questionnaire (PDRQ-9) is widely used to assess this relationship. However, there are no quality categories that can be derived from the instrument's score to facilitate understanding and decision-making. Objectives This study aims to establish categories of the quality of the relationship based on the PDRQ-9 score. Methods A latent class analysis (LCA) was conducted using interviews with 6160 users of primary health care units throughout Brazil to define different homogeneous response profiles. The Youden index was used to determine the cut point between classes. Results LCA identified the presence of two response profiles, one associated with a high evaluation of the quality of the doctor-patient relationship and another associated with a moderate evaluation. The cut point between classes, established through the Youden index, was 3.5 (on a possible score range of 1-5) or 31 (on a possible score range of 9-45). The cut point demonstrated high accuracy (0.94), sensitivity (0.96), and specificity (0.98). Conclusions The categorization proposed in this study enhances the interpretability of PDRQ-9 results, providing a practical framework for assessing the quality of the doctor-patient relationship. By establishing actionable quality categories, this tool could support targeted interventions, such as performance feedback and training, aimed at fostering empathy, communication, and trust in healthcare settings.