The problem of appointment scheduling in outpatient clinics: A multiple case study of clinical practice

•Through multiple case-study research and follow-up workshops the appointment scheduling framework is assessed.•The context of appointment scheduling has changed substantially compared to the setting that the operations-research literature largely assumes.•Practitioners almost universally perceive idle time as a minor issue and are unaware of the trade-offs that are being made.•Directions for developing the theory on appointment scheduling is provided to overcome the disconnection between theory and practice.•Practical implications are provided for improving the performance of scheduling in outpatient clinics.