INDUSTRIAL ENGINEERING APPLICATIONS IN HEALTH CARE SYSTEMS:APPLICATION OF SCHEDULING METHODOLOGIES

APPLICATION OF SCHEDULING METHODOLOGIES

Introduction

In health care systems, the term scheduling is used in a number of different ways. It can refer to the way in which appointments are scheduled for patient visits, testing procedures, surgical procedures, and the like. This form of scheduling is called work scheduling because patients represent work. In certain departments, it may be possible to move the workload from peak periods to periods of low demand to balance the workload. An example is an outpatient clinic where only a given number of appointment slots are made available. The number of appointment slots in a session determines the maximum number of patients that can be seen during that session, thereby restricting the workload to a defined level. In other departments, such as an emergency room, the patients or workload cannot be scheduled.

Another use of the this term is in the scheduling of personnel in a department based on the varying demand for services during the various hours of the day and days of the week while providing equitable scheduling for each individual over weekends and holidays. It must be noted that in the inpatient setting in health care, certain staff, such as nursing staff, need to be scheduled for work even over holidays. In the scheduling of personnel, each individual is given a schedule indicating what days of the week and what hours of the day he or she would be working over a period.

Work Scheduling

Some of the areas where work scheduling is possible are elective admission scheduling, case sched- uling in operating rooms, appointment scheduling in outpatient clinics, and appointments for radio- logical procedures and other testing such as amniocentesis. These are the areas where there is not an immediate and urgent need for services. To help determine the demand for services and understand the variability in demand, the workload data are collected by day of the week and hour of the day. In certain areas, it may be possible to smooth out the peaks and valleys in demand. For example, workload at a call center, where patients call by phone to schedule an appointment, can be shifted from busy hours to slow hours by playing a message on the phone as the patients wait to be served advising them to call during specific periods for reduced wait. After the workload has been smoothed, a decision is made to meet the demand a certain percentage of the time. After the staffing requirements are determined for this demand level using the methodologies discussed in the last section, staff is scheduled. Workload will then basically be restricted by the staff schedule.

Appointment slots are created based upon the type of work to be done and the number of providers available by hour of the day and day of the week. Appointments are scheduled as patients call for appointments. Once the appointment slots are filled, no additional work is scheduled. Appointment scheduling can be done using a manual system where an appointment book is maintained and the appointments are made by filling in the available slots. A number of computerized systems are on the market that basically allow the computerization of manual appointment books. These systems have the capability to search for available appointment slots meeting the time restrictions of the patient.

5.2.1. Appointment Scheduling in a Primary Care Clinic

Most people have a specific physician whom they see when they have a health-related problem. Individuals belonging to an HMO (health maintenance organization) select a primary care physician who takes care of all of their health care needs. For infants and young children, this would be a pediatrician, and for adults and teenagers, an internist or a family practitioner. Appointment sched- uling or work scheduling in a primary care clinic (internal medicine) is discussed here.

An internal medicine clinic had been struggling with the appointment scheduling issue for a period of time. In particular, they wanted to determine the number of slots to be provided for physical exams, same-day appointments, and return appointments. The first step was to estimate the total demand for physical exams and for other appointments in the clinic. Data on average number of visits per person per year to the internal medicine clinic were available from past history. Multiplying this number by the total number of patients seen in the clinic yielded an estimate of total number of visits to be handled in the clinic.

The number of visits to the clinic varied by month. For example, clinic visits were higher during the flu season than in the summer months. Past data helped in the estimation of the number of visits to be handled each month. It was determined that the number of visits varied by day of the week, too. Mondays were the busiest and Fridays the least busy. The number of visits to be handled each day of the month was estimated based on this information. Staff scheduling was done to meet this demand. The total number of appointment slots was divided among physical exams, same-day visits, and return visits based on historical percentages. Other issues such as no-show rates and overbooking were also taken into account in appointment scheduling.

Personnel Scheduling

Once the work has been scheduled in areas where work scheduling is possible and the staffing requirements have been determined based upon the scheduled work, the next step is to determine which individuals will work which hours and on what days. This step is called personnel scheduling. In other areas of the hospital, such as the emergency room, where work cannot be scheduled, staffing requirements are determined using historical demand patterns by day of the week and hour of the day. The next step again is to determine the schedule for each staff member.

The personnel schedule assigns each staff member to a specific pattern of workdays and off days. There are two types of scheduling patterns: cyclical and noncyclical. In cyclical patterns, the work pattern for each staff is repeated after a given number of weeks. The advantage of this type of schedule is that staff members know their schedules, which are expected to continue until there is a need for change due to significant change in the workload. The disadvantage is the inflexibility of the schedule in accommodating demand fluctuations and the individual needs of workers. In noncyclical schedules, a new schedule is generated for each scheduling period (usually two to four weeks) and is based on expected demand and available staff. This approach provides flexibility to adjust the staffing levels to expected demand. It can also better accommodate requests from workers for days off during the upcoming scheduling period. But developing a new schedule every two to four weeks is very time consuming.

A department may allow working five 8-hour days, four 10-hour days, or three 12-hour shifts plus one 4-hour day. The personnel schedule has to be able to accommodate these various patterns. The schedule must also provide equitable scheduling for each individual when coverage is needed over weekends and holidays.

Personnel schedules are developed by using either a heuristic, trial-and-error approach or some optimization technique. Several computerized systems are available using both types of approaches.

Warner (1974) developed a computer-aided system for nurse scheduling that maximizes an ex- pression representing the quality of schedule subject to a constraint that minimum coverage be met. Sitompul and Randhawa (1990) give detailed review and bibliography of the various nurse-scheduling models that have been developed.