Keywords: Parathyroid Hormone; Urolithiasis; Vitamin D

Purpose: Adherence to preventive recommendations improves clinical outcomes and is compulsory for long-term prevention in urolithiasis patients. Service quality can affect patients’ adherence to treatment and care. The purpose of this paper is to compare perceived service quality, using the SERVQUAL model, between urolithiasis patients who were nonadherent to their follow-up visits and those who were adherent, in a stone prevention clinic, Tehran, Iran. Design/methodology/approach: This was a cross-sectional study on patients with urolithiasis referred to the Shahid-Labbafinejad Hospital stone prevention clinic between 2010 and 2014. All patients withdrawing from follow-up visits were selected as the nonadherent group. Patients with follow-up visits were randomly selected and appointed as the adherent group. Data included demographic, service quality (assessed using the SERVQUAL) and a questionnaire about the reason for withdrawal from follow-up visits. Man–Whitney U test, χ² and binary logistic regression were used for data analyses. Findings: In total, 531 nonadherent and 51 adherent patients entered the study. SERVQUAL results revealed that patients’ expectations were significantly higher than their perceptions in all five service quality dimensions in both groups. The adherent group had better-quality scores. Responsibility, assurance and empathy scores significantly increased patient adherence odds. Research limitations/implications: Uni-center design; missing data, such as socioeconomic status and disease severity, which may influence treatment adherence; and missing data regarding adherence to medication and dietary advice were limitations. Practical implications: Service quality needs to be improved in all dimensions. Originality/value: Since responsiveness, assurance and empathy dimensions determined patients’ adherence, giving special attention to these dimensions could improve patient adherence.