Redesigning outpatient clinics’ appointment systems for serving chronic patient populations

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Redesigning outpatient clinics’ appointment systems for serving chronic patient populations

Master Thesis

Author Sebastiaan v. Buizen Student number 1971360

E-mail s.m.van.buizen@student.rug.nl

Master Program Technology and Operations Management

Institution Rijksuniversiteit Groningen – Faculty of Economics and Business Supervisor RUG Dr. ir. D.J. van der Zee

Second assessor Dr. H. Broekhuis Supervisors UMCG R. P. Borgers

T.J.J. Hoogstins

Date 23 June 2014

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Abstract

Purpose – The objective of this study is to design an appointment system which can efficiently fulfill the needs of a chronic patient population, consisting of multiple patient groups, with regard to short admission times and a high quality of treatment. The insights gained in this study can help practitioners to design appointment systems which are better suited for serving chronic patient populations, consisting of multiple patient groups, by allocating the right amount of resources to each group.

Method – A design-science research approach is used in studying elements of the appointment system. First the literature is reviewed to identify 1) basic elements of an appointment system and 2) existing insights on how to design an appointment system. Then literature, interviews and company data are used in describing, analyzing and redesigning elements of the appointment system used in the IBD outpatient clinic of the University Medical Center in Groningen. The redesigns are tested by means of a simulation study.

Findings – Simulation results show that a patient doctor coupling works restricting in planning acute patients. When the link is broken the admission times for acute patients are significantly shorter. Furthermore a trade-off is identified in reserving slots for either acute or new patients:

Reserving slots for acute patients shortens their admission time but increases those of new patients and vice versa. In addition it was found that combination slots (i.e. slots reserved for both acute and new patients) work more efficiently than reserving slots for a single patient group.

Another finding is that reserving an amount of slots for a patient group is more effective when the amount of slots is larger than the long-term average demand. In addition the reserved slots are more efficiently used when they are concentrated near the beginning or near the end of a period.

Two scheduling rules were studied with the goal of providing an equal work load each week.

Results showed that even if the interval between appointments was shortened (resulting in a higher utilized system) the effects of a smooth schedule outweigh the effects caused by the higher utilization rate, resulting in shorter admission times for new and acute patients.

Conclusion – Breaking the patient doctor coupling in acute cases, reserving an amount of combination slots more than the long-term average demand, concentrating combinations slots near the end or near the beginning of the week and applying a work load smoothing scheduling rule can significantly increase the performance of the appointment system with regard to admission times, an efficient use of resources and quality of treatment.

Recommendations – Reconsider the norms set by the clinic, especially the patient doctor coupling. In addition the appointment system could be adjusted to include the previously mentioned points.

Key words – Appointment system design, Outpatient clinic, Chronic patient population, Slot policy, Admission time, Capacity allocation, Patient doctor coupling

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Preface

This master thesis is the final step in my student career and marks the end of my master program: Technology & Operations Management. The objective of this study is to design an appointment system which can efficiently fulfill the needs of a chronic patient population, consisting of multiple groups, with regard to short admission times and a high quality of treatment

Writing this master thesis has been an intensive but educational experience. Before writing this thesis I saw academic research as abstract and tedious work. However due to the design-science approach in this thesis I learned to appreciate some of the academic work and I experienced some real-world application of what seems to be only theoretical knowledge.

Ending my student career with a feeling of satisfaction would not have been possible without certain people. In the first place I would like to thank my supervisor Mr. V. D. Zee for his sharp, constructive and insightful comments throughout the process. His eager to provide me with feedback has impressed me. In addition I would like to thank Ms. Broekhuis for her useful feedback and for her participation in the several constructive discussions we have had.

Furthermore I would like to thank Mr. Borgers, Mr. Hoogstins and Ms. Nuus of the UMCG for their insightful comments during our meetings. Their expertise and knowledge about the subject is a clear sign of their professionalism and has encouraged me to pursue a career in the healthcare sector.

Groningen, 23 June 2014 Sebastiaan v. Buizen

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1 Introduction

In recent years a shift from curable to chronic diseases has been observed in developed countries (Boutayeb 2006). This shift requires a different approach in serving patient populations. A population of curable patients usually consists of one patient group.

Consequently the available resources are all used in serving this single patient group. A chronic patient population however regularly consists of multiple patient groups. The groups are often formed based on the activeness of the disease and each group therefore has different needs. The existence of multiple patient groups causes that the available resources have to be allocated among these groups. One way of doing this is by making use of an appointment system.

This paper provides a case based analysis of appointment system design within the outpatient clinic responsible for treatment of inflammatory bowel disease (IBD) within the University Medical Center of Groningen (UMCG). IBD is a chronic disease whereby the intensity of the disease changes over time. The population consists of several patients groups, each with different needs. Whereas new and acute patients require quick access to a doctor i.e. short admission times, control patients require regular appointments with their own doctor. This study investigates how appointment systems could be designed to efficiently allocate the available resources among patients groups in such a way that admission times are short for new and acute patients and control patients are treated by their own doctor.

The literature on appointment system design mainly has focused on optimizing a single performance criterion for a single group of patients. The main goal is often to make an efficient use of resources or to minimize waiting time for patients. An overview of literature in this category can be found in Cayirli & Veral (2003). Literature on designing appointment systems which serve multiple groups with distinctive needs is however scarce. In addition only a few studies have explored admission times as a performance criterion of the appointment system even though admission times are an important determinant of patient satisfaction. Long admission times could also cause negative medical consequences (Wensing & Elwyn 2002;

Huang 1994; Laine et al. 1996).

One example of a study which focuses on appointment system design with multiple patient groups is that of Klassen & Rohleder (2004). Klassen & Rohleder zoomed in on a particular element of an appointment system called the slot policy i.e. which slots are allocated to which patients. Klassen & Rohleder found that reserving slots for acute patients increased the admission times for control patients. Furthermore Klassen & Rohleder reviewed several scheduling rules which aimed to minimize patient waiting time. This study aims to add to this stream of literature by studying several elements of appointment systems in more detail. This will be done by studying how 1) the amount, position, type and timing of slot reservation, 2) the coupling between doctors and patients and 3) scheduling rules affect certain performance criteria: 1) admission times 2) the quality of treatment and 3) the efficient use of resource.

A design-science research approach was used during this study. The next chapter will explain this approach and the structure of the paper in more detail.

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2 Research objective and design

This chapter gives an overview of the scope and content of this research. Paragraph 2.1 explains the background and the motive for the study. Paragraph 2.2 describes the research objective.

Paragraph 2.3 discusses the design of the research.

2.1 Background

Traditional hospitals have been organized in departments. During a period of treatment patients will repeatedly be referred to several departments. This is not a patient friendly approach.

Several external stimuli, such as incentives to reduce costs and focus on service, have caused a transformation in the way hospitals are organized. Instead of organizing care in departments hospitals now organize care around the patient. An example can be found in the UMCG. A new care path was developed in which IBD patients were treated in an integral way by cooperation between several specialisms. This care path has been very successful which caused an increase in the IBD population served by the UMCG. However this increase has also caused a challenge for the UMCG in fulfilling the distinctive needs of the patient groups in a timely manner.

In 2008 a study was conducted (Hoogstins 2008) with the objective of identifying new insights in how to serve the specific needs of the IBD population. The study investigated the effects of 1) slot policies, 2) the preference of a patient to be treated by the own doctor and 3) various sizes of the population on the clinic’s ability to serve the population. A general conclusion from this study was that if doctor’s time could be allocated more flexibly that the performance of the system would increase.

Six years have passed since that study and several things have changed. The size of the IBD population served by the UMCG has increased further and the work load for doctors has increased accordingly. It has become difficult for the UMCG to treat all the IBD patients within acceptable time windows and guarantee short admission times. This study will build on the earlier findings of Hoogstins who used a spreadsheet model to arrive at his conclusions. This study will verify and extend Hoogstins’ findings by using a more precise simulation study. The model will be expanded by also considering the type, amount and position when reserving slots.

In addition several new slot policies are considered and a distinction is made between short- term and long-term control patients.

2.2 Research objectives

The objective of this study is to design an appointment system which can efficiently fulfill the needs of a chronic patient population, consisting of multiple groups, with regard to short admission times and a high quality of treatment.

Admission times are defined as the time between the request for an appointment and the scheduled time of that appointment (Gupta & Denton 2008).

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Page | 8 An efficient use of resources, i.e. fulfilling the needs of the population in an efficient manner, is defined as the percentage of doctor’s time which is used for consultation in comparison with the total time doctors are scheduled for consultation.

A high quality of treatment is defined as meeting the wish of patients to be treated by their own doctor. Not only does this increase the patient’s satisfaction but it also provides significant medical advantages (Mirzaei et al. 2013; Wagner et al. 1996).

2.3 Research design

The methodology used in this study is a design-science approach. In line with guidelines set out in literature (Hevner et al., 2004) the objective is to create an artifact: An appointment system as described in section 2.2. The next chapter will first review the literature to identify existing insights in appointment system design and in order to create a framework which lists the basic elements of an appointment system. The subjects of the then following chapters are formulated according to the steps taken in the regulative cycle of Van Strien (1997). These steps are listed in Table 1 and will be further explained below. In the end the findings will be discussed, the limitations of this research are formulated and future research opportunities will be identified.

Step In Cycle of Van

Strien (1997) Chapter Research question

3 Literature review on appointment system design: Identify insight on and elements of an appointment system.

1. System

description 4 What are the main elements of the system under study and how is the appointment system set up?

2. Analysis 5 How does the current appointment system setup perform and what causes this performance?

3. Design 6 How could the setup of the appointment system be redesigned to improve its performance?

4. Testing 7 To which extent can a redesigned appointment system improve its performance with regard to admission time, resource utilization and quality of treatment?

8 Conclusion, limitations and future research opportunities Table 1 - Overview research design

Step 1: System description

In this step the main elements of the system under study are identified. The setup of the appointment system is described in relation to the framework identified in the literature review.

The execution of this step was done by observing the actual system and by informal interviews with operators in the system. The earlier study of Hoogstins is also still relevant as it describes several aspects of the system which have not changed in the years which have passed.

Step 2: Analysis and diagnosis

The analysis describes and discusses the performance of the current appointment system setup.

A diagnosis of the system will lead to the causes which restrict the performance of the system with regard to admission times, quality of treatment and resource utilization. This step will be executed by investigating company data, literature and informal interviews with operational IBD planners.

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Page | 9 Step 3: Design

In this phase several suggestions for redesigning elements of the appointment system are proposed. Each suggestion is categorized according to an element in the appointment system.

The objective of these suggestions is to increase the performance of the appointment system with regard to admission times, quality of treatment and resource utilization. The suggestions are based on the diagnoses performed in step two, on findings from literature and on the earlier study of Hoogstins (2008).

Step 4: Testing

The final step involves testing the earlier proposed redesigns. A simulation study is used to do so. The choice for simulation is based on the fact that simulation can effectively cope with variability and interconnectedness (Robinson 2004), both of which are present in appointment systems. This method is also in line with other studies in this field of research which mainly use simulation as a tool for testing (Cayirli & Veral 2003). The simulation study clarifies how redesigning an element of the appointment system impacts its performance.

To guide the simulation study a conceptual model will be developed. This model will summarize the main issues to which attention has to be paid in the simulation study concerning factors such a data requirements, validity, feasibility and the confidence which can be placed in the results (Robinson 2004).

2.4 Information sources

In cooperation with the logistics department of the UMCG a database has been build which forms the basis for the analysis and simulation modeling in this study. This database consists of administrative information such as when an appointment was made, when the appointment was executed, which doctor treated the patient etc. From this database other important information could be computed such as admission times. The database consists of the data from the last four years i.e. 2010-2014. Qualitative data was mainly obtained by observing the system and by informal interviews with operators and users within the system. Missing data was estimated and validated by several experts in the system i.e. doctors, planners and managers.

The next chapter will review the literature on appointment system design. It will identify existing insights with regard to appointment system design and builds a framework in which the basic elements of an appointment system are listed.

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3 Appointment system design

Appointment systems are used in a large variety of cases but this study focuses on appointment systems which serve multiple patient groups with distinctive needs. This is different from most appointment system research which often focuses on serving a single patient group. Due to the distinctive needs of each patient group multiple performance criteria are necessary to judge the performance of the appointment system in satisfying the specific needs of each group. This is also different from many studies which often focus on a single performance criterion. The goal of this chapter is therefore to review the literature on multi group, multi criteria appointment systems. Figure 1 serves as an overview of this chapter.

Figure 1 - Elements of an appointment system

The structure of this chapter is such that each element of Figure 1 will be discussed in more detail. The basic elements which can be found in any appointment system will be reviewed in section 3.1. Section 3.2 will zoom in on one particular element of an appointment system: The slot policy. Section 3.3 will discuss existing insights which need to be considered when designing a multi group, multi criteria appointment system. Section 3.4 identifies specific characteristics of chronic patient populations. Section 3.5 summarizes the main findings.

Supply

 # Services

 # Doctors

 # Slots per session

 Service times

 Lateness of doctors and interruptions

Demand

 Type of demand

 Arrival process o Punctuality o No-shows o Walk-ins o Companions

 Form of demand

Appointment system

 Slot policy

o Capacity allocation

 Type

 Amount

 Position

o Appointment scheduling

 Scheduling rule

 Patient classification

 Adjustment made to accommodate:

o Walk-ins o No-shows

o Emergency or acute cases

 Performance criteria o Cost based

o Time based o Congestion o Fairness o Combination

 Norms & regulation o Trade-offs

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3.1 Basic elements of an appointment system

Cayirli & Veral (2003) have conducted a literature review in which studies on appointment system design were categorized based on which element of the appointment system they studied. This led to a framework in which the basic elements of any appointment system are listed (Figure 1). These basic elements will be discussed in the following subsections.

3.1.1 Demand

An appointment system is often viewed from the viewpoint of the care provider. It therefore sees patients and their needs as demand. Demand can be homogeneous i.e. each patient requires the same treatment or heterogeneous i.e. patients have distinctive needs. In addition to the type of the demand another important characteristic is the arrival process of patients. According to Cayirli & Veral (2003) the arrival process of patients is characterized by four elements: 1) Punctuality of patients, 2) Presence of no-shows, 3) Presence of walk-ins (regular or emergency) and 4) Presence of companions.

A few years have passed since Cayirli & Veral's (2003) study was published and other researchers have identified more factors relevant to appointment system design which Cayirli &

Veral did not mention. One of these factors is the form in which the demand presents itself. This could be either in a batch (Patrick 2008) or in individual cases (Schütz & Kolisch 2012). In a batch situation patients are not processed individually and neither do they require immediately a new appointment. Instead the planner waits until the demand for a period is known and then plans all the appointments at once. Contrarily, the more common situation is where a patient individually requires a new appointment directly after treatment.

3.1.2 Supply

The supply consists of the services the clinic has to offer. Cayirli & Veral (2003) have identified several elements which characterize the supply in an appointment system: 1) Number of services, 2) Number of doctors, 3) number of appointments per clinic session, 4) Service times and 5) Lateness of doctors and interruptions.

3.1.4 Appointment system

The actual appointment system itself determines how the match between the demand and the supply is made. Cayirli & Veral (2003) identify four main elements of an appointment system: 1) The appointment rule (also called slot policy), 2) the use of patient classification, 3) adjustments made to reduce the disruptive effects of walk-ins, no-shows, and/or emergency patients and 4) performance criteria.

The first element, the appointment rule or slot policy, can be divided again in three sub- elements. These are 1) block size, 2) begin-block and 3) appointment interval. The block size specifies how many patients are seen within one appointment block i.e. slot. The begin-block specifies how many patients arrive at the start of a clinic session. The appointment interval specifies the length of a slot. These elements can be specific for each patient group.

Other researchers have been more accurate in describing the slot policy by for example including scheduling rules. Since the slot policy plays an important role in this study and Cayirli and Veral’s description is not complete this subject will be revisited in section 3.2.

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Page | 12 The second element of the actual appointment system, the use of patient classification, specifies if and how many patient groups are used within the system. Patient classification is often used with heterogeneous demand.

The third element of the actual appointment system consists of adjustments made to accommodate no-shows, walk-ins, urgent patients or emergencies. Many studies have researched how the disruptive effects of no-shows and walk-ins can be minimized. Examples can be found in Muthuraman & Lawley (2008); Vissers (1979) and Yang, Lau, & Quek (1998). How to accommodate emergencies however is not that clear.

The fourth element of the actual appointment system consists of performance criteria. According to Gupta & Denton (2008) the goal of an appointment system is to deliver timely treatment but also to provide a smooth and efficient work flow in which patients preferences can be honored.

It therefore has to match supply and demand. Performance criteria can be used to measure the extent to which the appointment system matches supply and demand. They are also used by operators within the system to guide decisions, for example by planning patients before a certain date in order to satisfy the criteria.

Cayirli & Veral (2003) have again provided a list of performance criteria. These are: 1) Cost- based measures, 2) Time-based measures, 3) Congestions measures and 4) Fairness measures.

In addition the utilization of the system, i.e. the actual time that is used for treating patients against the planned time, is also an often used criterion measurement (Gupta & Denton 2008). A combination of performance criteria can be used when the demand is heterogeneous and each group has distinctive needs.

Cayirli & Veral (2003) only give a short description of the elements in an appointment system.

These are summarized in Figure 1. For most elements this summary suffices. However in this study slot policies will play an important role. The next section therefore will discuss this element of an appointment system in more detail.

3.2 Designing a slot policy

According to Schütz & Kolisch (2012) the problem of scheduling clients to appointments (i.e. the slot policy) consists of three parts. These parts are capacity allocation, appointment scheduling and short-term decisions on the day of service. This study focuses mainly on capacity allocation and appointment scheduling.

3.2.1 Capacity allocation

Capacity allocation decides how much capacity (i.e. the amount of slots) is allocated to each patient group. This problem only exists when the demand is heterogeneous and patient groups are used within the appointment system. In healthcare capacity allocation is usually based on the number of consults (i.e. slots) required by a patient group (Patrick 2008).

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Page | 13 A special group which requires capacity is that of the acute patients. Due to their unpredictable demand is it difficult to determine how much capacity should be allocated to this group. Studies such as Klassen & Rohleder (1996) indicate that a trade-off exists between allocating capacity to acute patients and other groups. The more capacity is allocated to acute patients the higher the chance is that they can be treated quickly. However the chance on not using an acute slot also increases. This unused slot would otherwise be used for serving other patient groups. Thomas et al. (2001) found that for a small mean acute demand a relatively large percentage of excess capacity is needed to eliminate excess waiting time.

Another aspect of capacity allocation is when the capacity is planned (i.e. the position of the slot within the period). It could be that having the same amount of slots each day produces satisfactory results. However in some cases, when demand is skewed, an uneven distribution of slots might give better results than an even distribution, as is suggested by Klassen & Rohleder (2004).

The type of slots also needs consideration. Slots could be reserved for a single patient group or could be shared by multiple patients groups. In queuing theory it has been shown that average waiting time for customers in a single line for multiple servers is lower than when each server would have its own queue (Hopp & Spearman 2011). As a consequence fewer servers are necessary to achieve the same performance. Consequently reserving slots for multiple patient groups (i.e. a single line) might produce better results than dedicated slots (i.e. multiple lines).

3.2.2 Appointment scheduling

Appointment scheduling is the step after capacity allocation. Once each patient group is allocated capacity the question becomes which patient receives which slot. Scheduling rules (i.e.

in which order patients are treated or receive a slot (Klassen & Yoogalingam 2013)) are widely studied with regard to waiting times. Recent literature has shown that a dome-shape scheduling rule, where short slots are planned first, followed by longer slots and ending with short slots again, are generally performing better than traditional rules such as first come first served (Klassen & Yoogalingam 2009).

When a scheduling rule is used to minimize waiting time the order of magnitude is often minutes: The scheduling rule is meant to optimize daily operations. Scheduling rules could however also be used in optimizing longer time periods.

Control patients for example could require two consults per year. After a consult the next appointment is directly plant, i.e. six months in advance. A control patient is often not required to be seen exactly in six months, a few weeks earlier or later is acceptable. The scheduling rule could use this planning window in considering the work load per week and then planning the control patients in the least utilized weeks. The scheduling rule could then balance the work load per week so that an even number of control patients are seen each week. To the author’s knowledge no research on such scheduling rules or slot policies is conducted thus far.

The next section will discuss some specific characteristic of multi group, multi criteria appointment systems.

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3.3 Characteristics of multi group, multi criteria appointment systems

Since the pioneering research of Bailey (1952) on appointment scheduling many researchers have tried to further improve appointment scheduling mainly by focusing on scheduling rules (section 3.2.2). Most researchers tried to develop a general scheduling rule which performed well in many different situations. At a certain point however a new thought emerged: In order to further improve the performance of an appointment system more specific scheduling rules were necessary to fit complex situations.

At this point researchers began to recognize that making a distinction between patients (i.e.

forming patients groups) could improve the performance of appointment systems. Cayirli &

Veral (2003) explain that making a distinction between patient groups can increase the performance of the appointment system when the groups have distinct needs. However the use of patient groups also introduced new difficulties which are explained in the following subsections.

3.3.1 Less flexibility

Cayirli & Veral (2003) note that multiple patient groups make designing an appointment system more difficult. By limiting the assignment of patients to slots reserved to that patient group the planner has less flexibility in planning patients. In addition the capacity allocation might be based on long-term averages however the day-to-day variation could be such that each day there are too many or too few slots (Rohleder & Klassen 2000).

3.3.2 Norms & regulation

It was noted by Gupta & Denton (2008) that scheduling patients might be difficult due to constraining norms and regulations. Governmental rules increasingly dictate which performance criteria a care provider has to fulfill. In addition patient organizations and insurers also limit the flexibility of the care provider for example by requiring a doctor to physically examine a patient before prescribing an expensive medicine. Although these rules also apply in single patient group situations the notion of multiple patient groups imply that more rules apply.

Furthermore Gupta & Denton (2008) mention that care providers themselves also set internal norms or regulation which have to be attained. Examples can be found in minimizing costs by not allowing overtime or by increasing patient satisfaction due to only allowing treatment by the own doctor (Mirzaei et al. 2013; Wagner et al. 1996).

3.3.3 Trade-offs

Klassen & Rohleder's study (1996) was one of the first which examined the problem of serving multiple patient groups with distinctive needs within one appointment system. They studied several scheduling rules in planning appointment slots for two groups. These groups were distinctive in the variation in service time they had: Low variance and high variance patients.

The scheduling rules were judged on two criteria: Client waiting time and doctor idle-time. Their results showed that there was a trade-off in serving the groups: Reserving more slots for one group meant a decrease in performance of the other group.

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Page | 15 This trade-off has been a key characteristic of multi group, multi criteria appoinment systems. In the case of Klassen & Rohleder (1996) this trade-off was between client waiting time and doctor idle-time. Other studies have built on these results and include: Cayirli, Veral, & Rosen (2006);

Denton & Gupta (2003) and Kolisch & Sickinger (2008). Gupta & Denton (2008) however highlight that other trade-offs, such as admission time versus quality of treatment, have not received that kind of attention.

3.4 Characteristics of chronic patient populations

In addition to the difficulties of working with multiple patient groups the chronic character of some diseases introduces even more difficulties when designing an appointment system. The following sub-sections will highlight some of these.

3.4.1. Admission time

As was noted by Gupta & Denton (2008) most studies have focused on minimizing patient waiting time when designing appointment systems, i.e. the time between the arrival of a patient at the care provider and the start of the consult. Especially for acute and new patients however admission times are important as well. Admission times can be defined as the time between a call for an appointment and the date of the appointment (Klassen & Rohleder 2004).

Due to sudden changes in the disease’s activeness patients sometimes need quick admission. In a chronic patient population the patient could experience an acute state several times in his lifetime. Short admission times are not only important to minimize the discomfort of a patient.

Several researchers noticed that long admission times can have negative medical consequences.

If complaints are not attended soon they can increase in severity which can make treatment more difficult and time consuming. Long admission times are also a major source of patient dissatisfaction (Huang 1994; Laine et al. 1996; Wensing & Elwyn 2002). It is therefore recommended to consider admission times when designing appointment systems. There is however little research concerning admission times in chronic patient populations.

3.4.2 Patient doctor coupling

Chronic patients have developed a continuous need for care. Due to the regular intervals with which chronic patients see their treating doctor, they develop a sort of personal relationship with this doctor. Most chronic patients therefore prefer to be always treated by the same doctor.

Treatment by their own doctor increases the patient’s satisfaction with the service. Research did also find that a dedicated doctor provides better care decisions since the doctor knows the specifics of the patient and can better judge what is necessary for fast and effective treatment (Wagner et al. 1996; Mirzaei et al. 2013).

Although the medical and social benefits resulting from a patient doctor coupling are clear the logistical effects are not. Especially for acute patients, who are already limited by a small selection of short-term slots available, treatment by the own doctor is another limitation to the planner’s flexibility. Gupta & Wang (2008) studied the patient doctor coupling on a basis of costs. They found that very loyal patients (i.e. who demand to be treated by the same doctor always) limited the clinics performance due to the inability to use different doctors as substitutes in case of a high work load for that particular doctor. It was also noted that a balanced work load among the doctors reduced the negative effects of patient loyalty.

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3.5 Summary

This chapter has reviewd the literature on appointment system design. Basic elements of an appointment system were identified. These elements are summarized in Figure 2. Furthmore the design of a slot policy was reviewed. It was also noted that desgining an appointment system for multi group, multi criteria situations is more difficult due to less flexibility for the planner, norms & regulation and the trade-off effects in serving multiple groups. Furthermore it was concluded that the literature thus far has not given much attention to 1) admission times, 2) the use of scheduling rules or slot policies to balance work load and 3) the logistic effects of a patient doctor coupling, when serving chronic patient populations.

Figure 2 - Elements of an appointment system

The objective of this study is to design an appointment system which can efficiently fulfill the needs of a chronic patient population, consisting of multiple groups, with regard to short admission times and a high quality of treatment. In this chapter is has become clear what elements to account for when designing an appointment system for serving multiple patient groups with distinctive needs, which is assessed on multiple performance criteria. The next step is to redesign elements of the appointment system in order to satisfy the objective. This will be done with the help of a case, the IBD clinic in the UMCG. The next chapter will therefre first review how the UMCG has set up its current appointment system with regard to the elements listed in Figure 2.

Supply

 # Services

 # Doctors

 # Slots per session

 Service times

 Lateness of doctors and interruptions

Demand

 Type of demand

 Arrival process o Punctuality o No-shows o Walk-ins o Companions

 Form of demand

Appointment system

 Slot policy

o Capacity allocation

 Type

 Amount

 Position

o Appointment scheduling

 Scheduling rule

 Patient classification

 Adjustment made to accommodate:

o Walk-ins o No-shows

o Emergency or acute cases

 Performance criteria o Cost based

o Time based o Congestion o Fairness o Combination

 Norms & regulation o Trade-offs

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4 System description

This chapter will describe the case that will be used throughout this study and does so by reviewing how the UMCG has set up its appointment system with Figure 2 in mind. The question which is the main topic of this chapter is:

1. What are the main elements of the system under study and how is the appointment system set up?

The case consists of the IBD outpatient clinic in the UMCG. Figure 3 gives an overview of the system. New patients enter the population (inflow) and remain in the population until they go to another hospital or die (outflow). In the meantime patients cycle through the system by regularly visiting the outpatient clinic. In addition patients and the outpatient clinic interact with the appointment system by planning, executing and administrating appointments. The extent to which the appointment system can match supply and demand is measured in the performance section. The main elements from Figure 2 (demand, supply and the actual appointment system) are clearly recognizable.

This chapter will continue by systematically describing how the UMCG IBD clinic has set up its current appointment system by considering each element of Figure 2 in light of the case. The first element is demand.

Figure 3 - System overview

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4.1 Demand

The demand consists of patients with a form of inflammatory bowel disease (IBD). IBD is an overarching term for a group of chronic diseases concerning inflammations in the stomach and the bowel. The intensity of the disease changes over time. Periods in which the disease is in remission are exchanged with periods in which the disease is active. This transition can occur gradually or suddenly. IBD consists of chronic diseases: There is currently no permanent treatment.

4.1.1. Type of demand: heterogeneous

Due to changes in the activeness of the disease over time several patient groups can be identified based on the current state of a patient’s disease. The demand is consequently heterogeneous.

Four patient groups can be identified, each with their own needs. These will now be discussed.

4.1.2 Patient groups New patients

New patients arrive in the IBD clinic due to the General Practitioner (GP), another hospital or via another clinic within the UMCG. For this patient there is a presumption that the patient could have IBD but is has not been confirmed yet. Their first consult requires 40 minutes.

New patients value short admission times greatly. They experience much discomfort, are uncertain about what is happening to their body and waiting on test results in this situation can be nerve-racking. A quick diagnosis is therefore highly appreciated by new patients. The patient will be considered a control patient after he has been diagnosed with IBD and has received his first consultation.

Acute patients

The course of IBD diseases is hard to predict and flame-ups can be sudden and severe. Patients by whom the disease is in remission can suddenly experience intense discomfort. In these acute cases patients require quick consultation with a doctor to receive treatment. The UMCG has a policy where general acute patients (for example victims of a car accident) have to be seen and treated within a day. IBD patients are however not that critical: The norm admission time for acute treatment is eight days (originating from a medical guideline on IBD diseases).

For acute patients admission times are very important. The sooner the admission is the sooner patients receive treatment and alleviation of their complaints. Delayed treatment could cause an intensification of the complaints and could make the treatment more difficult and time consuming. Treatment by the own doctor is preferred. An acute consults requires 20 minutes.

Short-term control patients

After an acute admission doctors want to see the former acute patient on a short notice for a control visit. Generally the time interval for this control visit is six to twelve weeks. In this study this patient group is called the short-term control patient group. A control consult requires 20 minutes. Whereas long-term control patients live with the disease in a state of remission, short- term control patients experience an active state and therefore require more care.

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Page | 19 Both admission times and regular appointments by the own doctor are important for this patient group. The patient requires a control visit on a short-term to adjust medication or other adjustments to control the active state of the disease. If no capacity is available then the condition of the patient might worsen again. Much earlier than planned visits also are not desirable since the patient needs some time to stabilize after an acute admission.

Long-term control patients

Long-term control patients are those whose disease is in a state of remission. During control visits the patient expresses his complaints and informs the doctor about the course and current state of his disease. These control visits are important for doctors to keep up to date with the state of the disease of his patient so he can adjust the treatment and minimize the discomfort for the patient. This personal approach is the main reason for the loyalty of patients to a doctor.

Admission times are less important for control patients due to the long intervals between control visits. The time between control visits varies depending on the state of disease. Most control patients have two control visits per year while some have up to four control visits per year. A control consult requires 20 minutes.

Regular appointments are important for control patients. As was explained control visits are important to keep the disease in check. It is less important when exactly the control visits are planned. The three or six month interval between visits is not rigid: Two weeks earlier or later is acceptable. There is however no guideline on what exactly is an acceptable planning window.

4.1.3 Arrival process

The next element in Figure 2 is the arrival process of patients. Each patient group has their own way of entering the clinic. Furthermore some groups are predictable while others are not. Each group also has different needs. These are summarized in Table 2.

Figure 2 also listed punctuality, no-shows, walk-ins and the presence of companions as part of the arrival process. The effects of punctuality, no-shows and the presence of companions are usually in the order of minutes while this study focuses on admission times, which are generally in the order of days. The influence of not considering these effects should therefore be small.

Walk-ins do not occur within this IBD clinic: A consult can only be obtained by making an appointment.

Patient

group Enters the clinic

based on: Stochastic

nature? Main need What is important?

New patients A referral from GP, a

hospital or a clinic Yes Diagnosis and

treatment Short admission time Acute patients A call for an

appointment Yes Treatment Short admission time, preferably own doctor Short-term

control patients

Indicated by doctor No Control visits and medication

adjustment

Short admission time, regular visits, own

doctor Long-term

control patients

Indicated by doctor No Control visits and medication

adjustment

Regular visits, own doctor Table 2 - Patient classification and arrival process

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Page | 20 4.1.4 Form of demand: Individual cases

Patients individually visit the planner and require immediately a new appointment date after their consult. The demand is thus in the form of individual cases.

4.2 Supply

The next major element present in an appointment system is the supply. Figure 2 lists the number of services, doctors, slots per session, service times and lateness of doctors &

interruptions as part of the supply. Variation in service times and lateness of doctors &

interruptions are however more applicable when studying waiting time since their effects usually is in the order of minutes. Admission times on the other hand, which are studied in this paper, are often in the order of days. The effects of not considering variation in service time and lateness of doctors on admission times will therefore be small. The other elements of Figure 2 relating to the supply will now be discussed.

4.2.1 Number of services

The IBD clinic offers essentially only one service which is consultation with gastro-enterologists.

This can be physically or via the telephone. This study focuses on physical consults. During a consult test results and medication are discussed and might be altered. In case of new patients a consult consists of diagnostic activities. Other activities performed by gastro-enterologists, such as surgery or endoscopy, are not part of the IBD appointment system under study.

4.2.3 Number of doctors

There are four gastro-enterologists (doctors) working within the IBD clinic. Not every doctor is involved to the same degree. The total activities of the doctors are listed in Table 3.

Year 2010 2011 2012 2013

First visit 97 96 110 127

Control visit 1324 1474 1401 1527

No show 67 55 64 72

Telephone Consult 627 738 855 928

Total 2115 2363 2430 2654

Table 3 - Activities outpatient clinic for IBD patients

4.2.3 Number of slots per session

The clinic provides consult sessions from Monday through Thursday. The number of slots differs each day. Table 4 lists the basic weekly schedule. The names of the doctors are substituted with numbers. In addition there are junior doctors (following education) who are supervised by the four senior doctors. Junior doctors provide the same services as the senior doctors.

Day Number

of slots Served by

Monday 8 Doctor 1

Tuesday 9

Wednesday 9 Doctor 2

Thursday 9 Doctor 3

12 Doctor 4 4 Junior doctor

(circulating) 12 Junior doctor 1 12 Junior doctor 2 Table 4 – Number of

slots per clinic session

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Page | 21

4.3 Appointment system

The next major element in Figure 2 is the actual appointment system itself. The factors which make up the actual appointment system will now be discussed.

4.3.1 Slot policy Capacity allocation

The distribution (position) of slots and the amount of slots throughout the week were already listed in Table 4. Currently no slots are reserved for a certain patient group. The amount of slots per week is constant from week to week unless there are vacations or other interruptions. The capacity is fixed: It is not possible to plan additional slots when demand is exceeding supply.

Appointment scheduling

A consult i.e. slot takes 20 minutes. New patients require two slots; the other patient groups require one slot. One patient is seen per slot. There is no build-up of patients at the beginning of a session. Patients are planned first come first served (FCFS). In addition the patient is always planned on the closest slot available near the appointment date indicated by the doctor. There is no distinction made between patient groups when planning slots. Table 5 summarizes the current slot policy according to the elements in Figure 2.

Patient group

Capacity allocation Appointment scheduling Type of slot Amount of

slots Position

of slots Scheduling rule

New No reserved

or dedicated

slots Table 4 Table 4 FCFS – Patient is planned on the closest slot available to the

indicated appointment date Acute

Short-term control Long-term control

Table 5 - Slot policy 4.3.2 Patient classification

In the current appointment system only two classes are administered: Control patients and new patients. Acute patients are registered as control patients. There is also no distinction between long-term and short-term control patients in the appointment system. This makes it difficult to track the performance of the system per patient group.

4.3.3 Adjustment made to accommodate variability Walk-ins

The clinic does not serve patients who refer themselves to the clinic without appointment. New and control patients only can get access to a doctor through the appointment system. Acute patients are not considered walk-ins but emergencies and still require an appointment.

No-shows

Table 3 shows that the number of no-shows is very small: Less than 4% each year. No-shows are usually considered as wasted capacity. Hu (2013) however found that this specific IBD clinic managed to efficiently utilize no-show slots by rescheduling appointments. This is impressive considering that the clinic is an outpatient clinic (i.e. patients require time to travel to the clinic and a slot only offers 20 minutes).

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Page | 22 The findings of Hu (2013) could not be verified because the required data was not available within the dataset used in this study. If the findings of Hu (2013) however would still apply than the no-show rate could be even lower (Hu reported a no-show rate of 1,5%). In either case the wasted capacity resulting from no-shows is very small.

Emergencies or acute cases

No special measures are taken to accommodate acute patients: No slots are reserved for acute patients in the current situation. If an acute patient needs consultation but there is no open slot then the planner double books the acute patient with a regular control patient. This implies that the doctor reduces the length of the consult for both patients. Sometimes an acute patient is planned after the clinic ends, causing the clinic to run late. This has consequences for other activities of the gastro-enterologists such as the endoscopies in the afternoon.

4.3.4 Performance criteria

The IBD clinic uses several performance criteria in order to evaluate the clinic’s performance.

These performance criteria are: Admission times, resource utilization and quality of treatment.

Admission time

The Dutch government has regulated that the admission time for new patients should not exceed 28 days. Exceeding this norm lowers the reputation of the hospital. In addition insurance companies are beginning to only work with hospitals that are performing within the norms. The clinic therefore monitors the admission time for new patients and tries to remain below the norm. Section 4.3.5 will explore this in more detail.

Resource utilization

Due to the soaring healthcare costs in The Netherlands the UMCG is restrained in its yearly budget. It therefore has to work efficient to be able to serve all the patients with a limited budget. The goal is to maximize the resource utilization of the clinic without increasing admission times or lowering the quality of treatment significantly.

Quality of treatment

The UMCG wishes to meet patient preferences. As was identified in section 4.1.3, IBD patients prefer to be treated by the same doctor during their lifespan. The IBD clinic therefore strives to treat each patient by their own doctor. In this study this is the only determinant of the quality of treatment. In addition the influence of patient organizations is growing. Patient organizations can advise patients to avoid a certain hospital based on the experience of their members. If patients are therefore not satisfied with the quality of treatment of the UMCG the hospital might lose patients to another hospital.

Redesigning outpatient clinics’ appointment systems for serving chronic patient populations