Determinants of exclusive utilisation of scheduled and unscheduled primary care visits: a cross-sectional study in Portugal

Abstract Background Primary healthcare (PHC) is essential for delivering accessible, continuous, and comprehensive care. While scheduled and unscheduled visits are both integral to PHC, the exclusive use of one type has not been previously explored. Understanding the determinants of exclusive utilisation may inform service organisation and improve efficiency. Methods This cross-sectional study included adults (≥ 18 years) who consulted a family physician in the Local Health Unit of Entre-Douro-e-Vouga, Portugal, during 2023. Patients who used both scheduled and unscheduled visits were excluded from the analysis. Data were extracted from anonymised electronic health records. Sociodemographic and clinical variables were analysed using multivariate logistic regression to identify factors associated with exclusive appointment type. Results Among 28,213 patients, corresponding to 10.1% of the total, 68.0% used only scheduled visits and 32.0% only unscheduled visits. Scheduled visits were more frequent among women, local residents, employed individuals, and patients with diabetes, hypertension, obesity, cancer, or depression. Unscheduled visits were associated with men, students, and patients with asthma, dementia, anxiety, or cerebrovascular disease. Registration at a Family Health Unit (USF) was independently associated with higher odds of unscheduled visits (OR 0.54; 95% CI 0.50–0.59). Chronic conditions requiring structured follow-up were strong predictors of scheduled visits, while episodic or fluctuating conditions were linked to unscheduled utilisation. Conclusions Exclusive utilisation patterns in PHC are shaped by sociodemographic and clinical factors. Scheduled visits reflect engagement with preventive care and chronic disease management, whereas unscheduled visits respond to acute or unpredictable needs. These findings highlight the need to tailor care pathways to patient profiles and ensure that organisational models—such as USFs—balance accessibility with continuity. Strengthening structured follow-up and improving responsiveness for episodic conditions may enhance equity and efficiency in primary care delivery.