In this fast driven society, where the current climate in the healthcare sector demands efficiency and patients’ satisfaction in medical care delivery. The numbers of missed appointments, unnecessary waste of patient’s appointment time have caused an impending problem for healthcare institutions (Chua, 2010). Hence, there is need for integrated healthcare system to intervene and provide seamless care for both inpatients and outpatients. Therefore, an appointment booking system lies at the intersection of providing efficient and timely access to health services. Outpatient appointment booking is a subject of great interest to hospitals and other medical institutions (Koole, 2007).
The research on appointment scheduling has a long history, starting with the work of Welch and Bailey (1952). Their most famous result is the so-called Bailey-Welch appointment schedule, which states that two patients should be planned at the start of the day, and the other patients evenly spaced throughout the day, to oﬀset the bad eﬀect of no-shows and patient lateness (Welch and Bailey, 1952). Bailey (1952) already announced that an appointment system is a trade-off between doctors’ and patients’ waiting times. Although outpatient clinic’s average internal waiting times are long, doctors frequently have idle time. Patients who do not show up or who are late for their appointments cause idle time for doctors, leading to temporary underutilization of the outpatient clinic’s capacity. Gaps in the appointment schedules also cause underutilization of the doctor’s time (Bailey, 1954).
Research on outpatient clinics shows that waiting times are patients’ main dissatisfaction with hospital services (Huang, 1994). According to doctors and personnel, overtime and peak workloads are potential threats for the quality of care and the quality of labor, because they increase stress and time pressure. This research focuses on outpatient scheduling as a means to solve these problems for outpatient clinics. According to Cayirli (2003), access time is the time between the patient’s request for an appointment and his arrival at the outpatient clinic. A patient’s internal waiting time is the period between the scheduled starting time and the actual starting time of his consultation. Waiting time due to a patient’s early arrival is extracted from the internal waiting time, since it is not a consequence of the appointment system (Veral, 2003).
Accessibility to healthcare at affordable cost constitutes a high challenge in Nigerian like most African countries. The provision of quality, accessible and affordable healthcare remains a serious problem (Oba, 2008) and due to this fact, Nigerian was ranked to be low in healthcare delivery by international organisations. In other to address the situation in the health sector, and to provide universal access to quality healthcare service in the country, National Health Insurance Scheme (NHIS) was introduced in Nigeria (Johnson, 2009); with the aim of providing universal access to quality healthcare to all Nigerians. In 1993, the Federal Government directed the Federal Ministry of Health to start the scheme in the country in 1999 and the scheme was modified to cover more people (Adesina, 2009). NHIS became operational after it was officially launched by the Federal Government in 2005 (Kannegiesser, 2009).