Appointment scheduling for a hospital’s Pre-operative clinic

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Appointment scheduling for a

hospital’s Pre-operative clinic

Increasing patient’s service level alongside expanding the same-day service concept

Frederik Jan (Erik) Kloeze

MSc Technology Management erikkloeze@gmail.com

March 2012, Groningen

University of Groningen

Supervisor: dr. ir. D.J. van der Zee Co-assessor: dr. J.A.C. Bokhorst

Wilhelmina Hospital Assen

Supervisor: H. Holterman

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Management summary

There is a growing concern amongst health care providers to increase efficiency and work more effectively. Furthermore, there is a toppling noticeable in healthcare from the traditional functional organisation to a more horizontal and patients-central focus. A project set up by the Wilhelmina Hospital Assen in order to deal with both developments is the project called One Stop Shop (OSS). The One Stop Shop project provides patients referred to the Pre-operative clinic with a same-day service. Patients are referred to the Pre-operative clinic when their physician has determined that a surgery is required. At the Pre-operative clinic patients receive a pre-operative screening by an anaesthesiologist. The pre-operative screening is a requirement for a patient’s surgery to be scheduled. The trajectory offers several advantages: for patients it reduces the spread of appointments on different days since a succeeding appointment on the same day is offered, for the hospital, it provides for less patients remaining unscreened (and thereby un-schedulable) on the Operating Theatres waiting list as well as providing a competitive advantage compared to other healthcare providers.

In order to succeed a patient’s appointment with the physician by an appointment with the anaesthesiologist on the same day, the OSS trajectory is constructed. At the end of 2010, a pilot is set up in order to test the feasibility of this trajectory for a small group of patients. The pilot was positively evaluated by several stakeholders, and it was agreed on to continue with this project. In order to do so, research should be taken upon the question how the clinic’s appointment scheduling system has to be re-designed in order to allow for a greater group of patients to receive access to the trajectory.

In order to do so, the Pre-operative clinic’s organization and its appointment scheduling system are described in detail. The current performance of the clinic is analysed and relevant literature concerning the topic consulted. The constructed conceptual model shows an extended relationship, besides the traditional relationship in supply and demand, with the patient’s service- and the Pre-operative clinic’s utilization level. Patient’s service level is split up in two components: the accessibility for OSS patients and the virtual waiting time for non-OSS patients. OSS accessibility is defined as the percentage of patients, satisfying the criteria determining access to the OSS trajectory, which actually (can) receive access to the trajectory within two hours from the appointment with the physician. Virtual waiting time is defined as the number of days between the request for an appointment and the next available appointment. Both the demand for care and the supply of resources are seen to be related, as well as the utilization and patient’s service level. The appointment scheduling system is used as a moderator in order to control these relations. Using a simulation tool, the effects of several changes to the appointment scheduling system are evaluated with regard to the clinic’s utilization- and patient’s service level.

The One Stop Shop project group has set a criterion for the OSS accessibility, which should be at least 85%. Another criterion states that it is not allowed to alter the scheduling such that OSS patients are sub optimized over non-OSS patients. The diagnosis showed that the performance criteria currently are not being met, with the accessibility of the trajectory revealed to be 56,6%. The re-design presented in this research therefore does not merely focus on the expansion of the trajectory, but also on the impact of the trajectory on the performance criteria.

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to be known when, and how many, patients will arrive on a given moment in time. The clinic has constructed a set of rules determining a patient’s access to the trajectory. Using these rules, the amount of patients, and the required capacity for these patients, can be determined beforehand. With the criteria that a patient should receive access to the OSS trajectory within two hours from their appointment with the physician, the arrangement of the OSS slots in the clinic’s schedule is shown to be a key issue. As revealed in the diagnosis, before the consult(s) with a physician, there is no absolute certainty whether a patient will proceed for a surgery at the Operating Theatres. Beforehand, the arrangement of OSS slots thus cannot be determined based on the schedules from the different referring physicians.

Based on the Operating Theatre surgeries in the first half year of 2011, a method is constructed to reveal the actual demand for care from patients. Furthermore, a new set of criteria determining a patient’s access to the trajectory is constructed, providing access to 45-50% of the total number of patients undergoing an elective surgery. With this constructed flow of patients and the new set of criteria, the amount and arrangement of OSS slots in the schedule are determined. With a negative relation between assigning additional OSS slots and the clinic’s utilization level, two new schedules are created: a schedule with the expected average amount of OSS patients, and a schedule with a somewhat lower amount of slots for these patients. Using a simulation tool and four experimental factors, a 24 full factorial set of experiments is performed in order to reveal the effects of both the current and the two new schedules on the clinic’s and patient’s performance measures.

The experimental factors have shown divergent results. The most noticeable effects of the experimental factors over all three schedules are:

- The average increase of 40,5% in OSS accessibility and the decrease of 11,0% in non-OSS patients’ virtual waiting time by providing a greater degree of freedom in scheduling OSS patients, allowing OSS patients to be scheduled on both OSS and available other slots.

- The decrease of 24,1% in non-OSS patients virtual waiting time when the patient’s willingness to participate in the OSS trajectory is increased.

- The decrease of 11,5% in the non-OSS patient’s virtual waiting time when a greater length in a slot’s expiry period is assigned. The expiry period of a slot causes a dynamic in the schedule, since an unscheduled slot loses its specific assignment when not scheduled within a certain period.

Further, the newly constructed schedules show a significant increase in OSS accessibility when compared to the experiment using the set of experimental factors resembling the situation during the pilot: averaged over all other experimental factors the schedules show an increase of 94,4% - 106,62% in OSS accessibility. When compared to this pilot experiment, the most optimal simulation run reaches an increase of 118% in OSS accessibility to 77,5%, while having an acceptable effect on both the clinic’s utilization level as well as the virtual waiting time for non-OSS patients.

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Preface

This Master thesis forms the final hurdle in the graduation procedure for the Master degree program of Technology Management at the University of Groningen. The thesis is the result of a research project conducted at the Wilhelmina Hospital Assen. Started in May 2011, during a period of about five months, I have been actively involved in a project on providing patients a same-day service with the hospital’s anaesthesiologists.

Being part of a, for me, completely new environment at a hospital has been a great experience for me. Besides the challenges my research project provided for my academic competences, I have been able to learn how to adopt an attitude required in a ‘people’s organization’ which is noticeable different from a standard industrial (and hierarchical) organization. Although I will continue in a different environment, the journey in a healthcare business organization has been a valuable one. This research project has been conducted together with the One Stop Shop project team at the Wilhelmina Hospital Assen, being led by my supervisor H. Holterman. I would like to express my gratitude to the hospitals employees who have been involved in all the activities surrounding the project. In particular, I would like to thank H. Holterman for his enthusiasm and active involvement, for the interesting discussions and for providing me the opportunity to become part of the project. In addition, dr. R. Nijholt requires a word of thanks for her support and involvement during the entire research.

From the University of Groningen, two persons deserve some attention, University Supervisor dr. ir. D.J. van der Zee and University Co-assessor dr. J.A.C. Bokhorst. As my supervisor, mister van der Zee has provided the guidance and support a Master student seeks during his research project. The valuable discussions together with the critical attitude of mister van der Zee has motivated me even more for aiming at the highest possible result for this thesis. I would also like to thank mister Bokhorst for already providing his commitment in an early stage of this research project, and thereby providing valuable insights.

From the University Medical Centre Groningen, I would like to show my gratitude to Tsjibbe Hoogstins MSc for sharing his knowledge and ideas to construct a simulation tool without the use of discrete event simulation.

Finally, I would like to make a word of thanks to my friends and family who supported me throughout the entire project. Of them, I especially would like to thanks Suzanne Legtenberg MSc, who has been more than valuable during the early stages of this research project.

I hope the reader enjoys reading this thesis.

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1 1. Introduction

There is a growing concern amongst health care providers to increase efficiency and work more effectively. Several reasons are underlying to this concern: an aging population, rising healthcare expenditures and an increasing governmental pressure to reduce costs (Hulshof, Van Houdenhoven, & Hans, 2011). Another recent development lies in the reimbursement hospitals receive for treating patients, with the introduction of diagnosis-treatment combinations. A diagnosis-treatment combination describes the complete trajectory a patient goes through, including the total costs of this trajectory. Thereby it also determines the reimbursement and thus puts even more pressure on hospitals to work efficiently. Finally, there is a toppling noticeable in healthcare from the traditional functional organisation to a more horizontal and patients-central focus. In the traditional functional organisation, patients follow a pre-defined process. With the toppling in healthcare, the care is organised more around the patient. Like all other (Dutch) hospitals, the Wilhelmina Hospital (WZA) has to find a way to manage these new developments.

In the scope of hospitals working more efficiently, appointment-scheduling systems are an interesting field of research. Gupta & Denton (2008) state that “appointment scheduling systems lie at the intersection of efficiency and timely access to health services”. In an ever more competitive environment, patient satisfaction is becoming a key issue for hospitals (Gupta & Denton, 2008). Patient waiting times and waiting-room congestion are two of the few tangible quality elements in healthcare. Well-designed appointment systems have the potential to increase the utilization of expensive personnel and equipment-based medical resources as well as reducing waiting times for patients (Cayirli & Veral, 2003). One of the most important determinants of patient satisfaction is timely access to care (Huang, 1994) and (Gupta & Denton, 2008).

In the Wilhelmina Hospital (WZA) a trajectory, named One Stop Shop (OSS), is introduced by the anaesthesiologists of the Pre-operative clinic. The trajectory has the aim of decreasing patient’s access times to the clinic. Specifically, the aim is to provide the patient with a same-day access time to the clinic. This has been done in a pilot setting in which a limited pre-specified number of patients were given access to the One Stop Shop trajectory. The pilot provided a solid ground amongst the stakeholders in order to continue and expand the OSS trajectory. During the pilot, several questions arose as to how the pilot could be expanded, by including additional categories of patients, without a declining effect on the performance of the Pre-operative clinic.

1.1 Company description

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Wilhelmina Hospital Assen

Founded in 1907

Number of beds 276

Number of employees 1200

Number of Operating Rooms 6

Number of surgeries 10.000

Number of policlinic appointments > 200.000

Total revenue € 76.000.000

Table 1.1 Overview of general factors describing the Wilhelmina Hospital. The numbers are based on 2010.

With almost 300 beds, 1200 employees and 6 Operating Theatres, the hospital can be characterized as an average size hospital in the Netherlands.

As a general hospital the WZA provides medical care (consisting of diagnosis, treatment and aftercare) and related nursing and care. In total the hospital covers 17 different medical specialisms1. The WZA claims to be “a progressive hospital which accommodates its physician care on its patients and is cooperating actively with other health care providers.”2 The WZA’s mission is described as “supporting the patients in Assen and surroundings when answering their care, providing high quality care and striving for continuous improvement. The hospital is ambitious and innovative, and comes to the best possible result by a people-oriented manner. This takes place in a safe and familiar surrounding with the help of motivated employees.”

Figure 1.1 Front view of the Wilhelmina Hospital Assen

Originally defined by Porter in 1980, Treacy & Wiersema (1993) describe three basic value disciplines that can create customer value and provide a competitive advantage: operational excellence (excellent operations and execution), product leadership (strong in innovation and brand marketing), and customer intimacy (excel in customer attention and customer service). Based on the characteristics of the organization and the dynamics of the current health market, the WZA has chosen operational excellence to be the leading strategy for the upcoming years.

The WZA’s organogram3 shows the WZA is split up in four different clusters: Medical Support, Psychosocial & Rehabilitation, Care and Facility Management. This research is held within the cluster Care.

1_{Corporate Responsibility Report 2009 –}

http://www.wza.nl/media/25499/maatschappelijk%20verslag%20wza%202009.pdf

2

http://www.wza.nl/over-wza/over-het-wza

3_{Organization chart –}

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Cha pter: Intr o du ct ion

3 1.2 A patient’s pathway

Before elaborating on the One Stop Shop trajectory, the patient’s pathway through the hospital is explained. This point of perspective is from the Pre-operative clinic, which allows some primary terminology to be explained. In this research the terms ‘policlinic’, ‘specialism’ and ‘physician’ are used in a mix. There is a many to many relation between a policlinic and a specialism, and between a specialism and a physician. A specialism can belong to one or many policlinics, and a policlinic can belong to one or many specialisms. A specialism can be performed by several physicians with a physician belonging to one specialism. Due to the chosen perspective, the process overview only includes patients who undergo a surgery in the hospital, and thereby it does not cover alternative pathways.

Figure 1.2 A general overview of the patient’s pathway through the hospital from the perspective of the Pre-operative clinic

Figure 1.2 provides a general overview of the patient’s pathway through the hospital. The pathway starts with the patient’s referral by their general practioner to a physician. This could be to the orthopaedist, the gynaecologist or any other specialist from a specialism. After the referral, the patient has one or several consults with the physician. These consults take place at the policlinic of the concerned specialism.

During a surgery, the anaesthesiologist is responsible for the anaesthesia of the patient4. It is therefore required for a patient to have a consult with the anaesthesiologist before the surgery takes place. This consult, which is called the pre-operative screening, takes places at the Pre-operative clinic. The goal of the screening is to determine the patient’s health in relation to the anaesthetic treatment before, during and after surgery. A positive conclusion of the pre-operative screening is a mandatory requirement for the patient to undergo surgery. If the physician concludes that the patient has to undergo a surgery5, the patient has to be scheduled to receive the pre-operative screening at the Pre-operative clinic. Patients either are scheduled in succeeding to their

4_{In order to be correct, it should be noted that there are surgeries without the anaesthesiologist being}

responsible, for instance when the anaesthesia is admitted by the surgeon.

5_{Not all patients being referred to the physician will undergo a surgery, being that sometimes it is not}

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appointment with the physician or on the patient’s request. When directly not being scheduled, the patients are listed on the (virtual) Pre-operative clinic’s waiting list6. After receiving a positive conclusion of the pre-operative screening, the patient is listed on the OR waiting list. The scheduling of surgeries is done based on this waiting list. After the patient’s surgery, a phase of aftercare can follow, after which in general the patient’s pathway in the hospital ends.

Before the introduction of the pilot One Stop Shop trajectory, the appointment with the physician, the anaesthesiologist and the patient’s actual surgery are scheduled on three different dates. The One Stop Shop trajectory combines the patient’s appointment with the physician with a succeeding appointment on the same day with the anaesthesiologist. The appointment for the patient’s surgery remains on a separate day, foremost due to patient’ preferences. It can be stated that the One Stop Shop trajectory tries to minimize the waiting list for the Pre-operative clinic, and by accelerating patients through the process, tries to maximize the amount of schedulable patients on the OR waiting list.

1.3 One Stop Shop trajectory

In November 2010, the project group One Stop Shop started with the project ‘One Stop Shop Pre-operative clinic’ (in short One Stop Shop or OSS) in order to decrease patient’s access times to the clinic. With the toppling in healthcare to a more patients-central approach, the question is asked why a patient should receive an appointment for their pre-operative screening on a different day as the appointment with their physician. Therefore, instead of letting patients return to the hospital for their pre-operative screening on another day, the possibility is offered to link a patient’s appointment with both the physician and the anaesthesiologist on the same day. Offering a patient a direct succeeding access to the pre-operative screening following on their appointment with the physician can be seen as a ‘fast track’. Fast tracks are present in literature, with most fast tracks based on the patient’s medical condition, i.e. patients being too ill to wait for an appointment (Kinnersley, et al., 2000). The relation between supplying specialisms and the pre-operative screening however is not found in literature and therefore is rather unique.

From a patient’s point of view, with the One Stop Shop trajectory, the spread of appointments on different days is reduced, thereby saving the patient time and effort, which is preferred by patients (Kaandorp & Koole, 2007). Furthermore, the patient is set more central in the process, with activities being organized around the patient.

For the hospital, the OSS trajectory provides for several advantages. One out of three patients on the waiting list for the Operating Theatres consists out of patients which have not yet received their pre-operative screening. Due to this missing screening, these patients cannot be scheduled for a surgery. By performing the pre-operative screening in succeeding to the patient’s appointment with the physician, fewer patients remain without a pre-operative screening on the Operating Theatres waiting list. The trajectory also provides for a competitive advantage of the WZA compared to other hospitals. This is because of two reasons. First, in the relationship between hospitals and the insurance business, the insurance business is becoming increasingly strict in selecting hospitals for

6_{It should be noted that no actual Pre-operative clinic’s waiting list exists. Patients who have to undergo}

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which they guarantee a certain amount of treatments7. One of the hospital requirements for these treatments is a short access time of the pre-operative trajectory, which includes both the consult(s) with the physician as well as with the anaesthesiologist. Second, hospitals, just as regular businesses, operate in a competitive environment. Patients are free to choose the hospital in which they wish to receive their treatment. By (actively) providing patients with a same-day service for their pre-operative screening and thereby minimizing the amount of visits to the hospital, patients may be more inclined to get their treatment in the WZA.

The pilot phase of the trajectory is being held in order to become acquainted with the effects of the OSS trajectory on the Pre-operative clinic’s performance. Furthermore, although the focus is on One Stop Shop patients, it is not allowed to sub optimize this group of patients over other, non-OSS patients. Therefore, in the pilot, the group of One Stop Shop patients consists of just 10% of the total amount of elective Operating Theatre patients. During the pilot phase, a declining effect on the performance of the Pre-operative clinic is noticeable. It is seen that not all assigned One Stop Shop slots8 are assigned to patients, and therefore the utilization, measured on a daily basis, of the clinic decreases. The One Stop Shop project group has set several performance norms that a possible expansion of the pilot phase should fulfil. The performance measures are elaborated on in Chapter 4. The question is being asked by the WZA’s management team, how the trajectory can be expanded, while meeting these performance norms and without sub-optimizing OSS patients over non-OSS patients. This question forms the basis of the research.

1.4 Preliminary inquiry

“A necessary condition for product success is that a product offers perceived benefits to the customer” (Ulrich & Eppinger, 2008). As the One Stop Shop trajectory is a service offered to patients, the success of the project is decisive upon the willingness of patients to participate. The question can be posed if a specific patient or group of patients need is satisfied with a same-day access to the anaesthesiologists after the consult with their physician. Therefore, during one month, a questionnaire is held amongst all patients visiting the Pre-operative clinic. The questionnaire (in Dutch) can be found in Appendix 1. In order to categorize expected differences in outcomes, three characteristics are added to the questionnaire: age, gender and referring specialism.

A positive outcome of the questionnaire has been a precondition in order to continue with this research. Over 375 patients have answered the questionnaire, resulting in a response of more than 95%. The outcome of the questionnaire is clear; 75% of the patients prefer to link the appointment with their physician with an appointment with the anaesthesiologist, on the same-day. No significant differences were found upon the three chosen characteristics age, gender and referring specialism. Although the questionnaire was held anonymous, some patients who indicated not to prefer the trajectory stated that they did not mind to visit the hospital again on another day for the pre-operative screening. In the remaining of this research, the outcomes of the questionnaire are considered.

7_{As an example, the Dutch insurer Menzis is issuing so called ‘TopZorg’ predicates for hospitals who meet}

pre-defined requirements. These are issued for surgeries such as meniscus, breast cancer and tonsillitis. Patients undergoing surgery, for which the hospital does not have such a predicate, are not reimbursed (all) medical costs.

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6 1.5 Research structure

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Cha pter: Res earch des ign

7 2. Research design

In this chapter the research design is presented. In Section 2.1 the situation before and during the One Stop Shop pilot is described, leading to the problems of the One Stop Shop trajectory as well as the problems with expanding the One Stop Shop trajectory. Section 2.2 discusses the scope of the research, and in Section 2.3 a stakeholder analysis is performed. With the problem described, the scope set and the stakeholders identified, Section 2.4 presents the problem statement, which forms the basis for the conceptual model in Section 2.5. Section 2.6 finally provides an overview of the methodology used in the research.

2.1 Problem analysis

In this section, several topics are elaborated on. First, an overview of the Pre-operative clinic’s appointment scheduling system is provided, independent of the introduction of the One Stop Shop trajectory. Thereafter the situation before- and during the pilot of the OSS trajectory are described. The outline of both situations leads to the problems of the OSS trajectory as well as the problems with expanding the OSS trajectory. Finally, the relevance of the posed problem is discussed.

2.1.1 Pre-operative clinic appointment scheduling system

From a logistical point of view, the Pre-operative clinic is a coupling point which has multiple specialisms providing it with a flow of patients at the input side, and one single source for its output: the Operating Theatres. The routing of a patient through these stages is restricted in its sequence. The starting point will always be with a physician at a policlinic, via the Pre-operative clinic, to the Operating Theatres. Pre-operative screenings are being held by appointment and walk-in patients are not allowed.

Figure 2.1 Overview of the mix, and volume, of patients arriving at the Pre-operative clinic

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The Pre-operative clinic’s appointment schedule consists of two blocks: a morning and, after the lunch break, an afternoon block. Each block is divided in different periods with an equal length: slots. In the Pre-operative clinic’s schedule, each specialism is assigned an amount of slots for their patients. The number of slots per specialism in in line with the amount of capacity a specialism receives at the Operating Theatres. Each year, the amount of capacity a specialism receives at the Operating Theatres is determined. During the year there is a small dynamic in this assignment of capacity, as specialism can request for more- or less capacity in a given period. Practice shows that the amount of pre-determined capacity received still is a good indicator of the amount of capacity actually used during the year. Finally, the arrangement of slots in the Pre-operative clinic’s schedule is spread throughout the day. In the explanation box, an example about the arrangement of slots is provided. E X P L A N A T IO N

Assume that there are three different specialisms: A, B and C. Dependent on the amount of slots each specialism has been assigned at the Pre-operative clinic, the schedule could look like AAABBBCCC or AABBBC. With the arrangement of slots being spread throughout the day, the schedule most likely would look like ABCABCABC or ABCBAB.

Explanation 1 – Arrangement of slots

2.1.2 Outline of the situation before- and during the One Stop Shop pilot

Before the introduction of the pilot One Stop Shop trajectory, appointments for patients at the Pre-operative clinic are scheduled in advance. After the physician has concluded that the patient has to undergo a surgery, an appointment is scheduled for the patient to receive its pre-operative screening. On a separate day, the patient returns to the hospital and receives the pre-operative screening. Even though there are slots for patients from specific specialisms, in general, there is no distinction in the pre-operative screening for patients from different specialisms.

With the toppling in healthcare to a more patients-central approach, the question is being asked why a patient should receive an appointment on a different day then the appointment with their physician for the (mandatory) pre-operative screening. This led to establishment of the project group One Stop Shop (OSS) that commenced a pilot in November 2010. In the pilot, there are three criteria in place which determine whether a patient is assigned access to the OSS trajectory, based on the patient’s age, medical condition and a pre-determined list of surgeries. These criteria give access to around 10% of the total amount of elective Operating Theatres patients to the OSS trajectory. As already outlined, the most noticeable objective of the project group is to offer patients the possibility for a pre-operative screening on the same day as the appointment with their physician.

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2.1.3 Problems with the One Stop Shop trajectory

Before the introduction of the One Stop Shop pilot, patient’ appointments are scheduled on a separate day as the appointment with their physician. With the number of available slots directly linked to the specialism’s available capacity at the Operating Theatres, the one-to-one relationship between the Pre-operative clinic and the Operating Theatres is persisted. Furthermore, as patients return to the hospital on a separate day, there is no need for a relation in the arrangement of slots in the physician’s schedule and the arrangement of slots in the Pre-operative clinic’s schedule.

The One Stop Shop group has set three conditions for the One Stop Shop trajectory9:

1) In order to gain access to the OSS trajectory, an OSS slot should be available in the Pre-operative clinic’s schedule for a patient within two hours, starting from the appointment-time with the physician10.

2) The service level11 of the trajectory should be such that 85% of the patients that fulfil the criteria should get the possibility to access the trajectory. With the criteria set such that around 10% of the total amount of elective Operating Theatres patients receives access, net 8,5% of the patients should get the possibility to access the trajectory.

3) The utilization of the Pre-operative clinic’s schedule should not be less than 85%.

The One Stop Shop trajectory thus does not solely offer a day service to patients, but a same-day service within a defined period. This requires that (1) a slot is available in the schedule on the same day and (2) the slot is available within a period of at most two hours. These conditions make the arrangement of slots for the One Stop Shop trajectory in the Pre-operative clinic’s schedule completely different from the arrangement of traditional slots. That is, the total amount of slots a specialism receives is still in line with the amount of capacity the specialism receives at the Operating Theatres. However, the arrangement of slots for the OSS trajectory becomes dependent on the arrangement of slots in the schedules of the eight different referring specialisms. For both the service- and utilization level criteria, there currently is no online measurement tool. Therefore, the degree in which the pilot One Stop Shop meets the set criteria cannot be verified.

Based on the criteria determining whether a patient receives access to the One Stop Shop trajectory, an average amount of slots required for the OSS trajectory can be estimated. However, as an OSS slot should be available within a given time period, the arrangement of OSS slots in the schedule is a key determinant of satisfying the service level requirement of 85%. The combination of the first two conditions with the third condition regarding the required utilization level makes the problem even more complex12.

Before elaborating on the increased complexity caused by the utilization condition, it can first be argued whether the schedule’s utilization should be (that) high. The description of a patient’s pathway in Section 1.2 showed that the Pre-operative clinic serves as a mandatory phase before the

9_{A full elaboration on the One Stop Shop’s objectives and conditions is provided in Chapter 4.}

10_{In practice, during the pilot, the secretary at the policlinic determines whether the patient meets the two}

hours norm.

11_{Service level refers to the extend in which delivery promises are kept, thereby honouring the delivery time}

given to the customer. Service level in this research is linked to the types of access delays a patient faces. See Section 2.5.1 for a further operationalization of service level.

12_{Although not specified in the project plan, the utilization condition is set provided that the amount of}

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Operating Theatres. From this perspective, the clinic should have to goal of supplying a sufficient flow of patients to the Operating Theatres. An increase in the available resources (either in staff or slots in the schedule) may lead to a lower utilization of the clinic’s schedule, but at the same time will increase the clinic’s flexibility in processing patients. Interviews revealed that when viewing from a cost perspective, an increase in available resources is not permitted. Therefore the amount of available resources should be used as efficiently as possible, thus increasing the utilization. However, reaching an as high as possible utilization of the clinic’s schedule might be undesirable, as the effect of internal or external disruptions increase with an increasing utilization level. In the project plan, the current performance levels are not mentioned. Therefore, the performance criteria as specified in the project plan have to be put in perspective with regard to the current- and with the desired performance levels, before striving for the highest utilization levels.

In practice, a well-known conflict between performance measures is the trade-off between utilization level and order flow time, with order flow time being indicative for the service level (Stoop & Wiers, 1996). By definition, when measuring on a daily basis, there is a negative relationship between utilization and service level: creating too much slots for the One Stop Shop trajectory increases the service level, but will decrease the utilization level. Vice versa, by not creating enough slots for the OSS trajectory, the utilization level will increase, but the service level diminishes. Furthermore, by creating additional slots for the One Stop Shop trajectory, regular slots of the participating specialism are retracted. This can have the effect of optimizing allocated slots in the schedule for patients of the One Stop Shop trajectory, over other groups of patients. Interviews revealed that from an ethical perspective, it is not allowed to alter the appointment scheduling system such that OSS patients are optimized over non-OSS patients.

Introducing a same-day service and reserving capacity for this in the clinic’s schedule, creates an uncertainty since it is unknown whether there is a patient available for this reserved capacity. Besides having an effect on the clinic’s utilization, this also has an effect on the daily variation in utilization. This daily variation can be seen as a determinant of the clinic’s daily workload. Although not specified in the project plan, with expanding the OSS trajectory, it should be prevented that this daily variation is resonating with the expansion of the trajectory. Within a limited range of utilization levels, the daily variation in utilization can even be regarded as more important than the utilization as such, since it determines the practicability of the trajectory.

2.1.4 Problem with expanding the pilot One Stop Shop

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amount of capacity to be allocated, the (historical) appointment data does not reflect the true demand. This is because it is unknown whether a patient preferred the specific date on which the appointment is booked, or that an earlier date for the patient was unavailable (Gupta & Denton, 2008). Furthermore, although there currently is no online measurement tool to determine the performance criteria, interviews revealed that it is expected that the performance criteria are not completely being met. However, since the trajectory received positive reactions from both patients as well as the participating specialisms, it is requested by the OSS project group to take research upon the feasibility of expanding the trajectory, with respect to the set performance criteria.

In order to be able to expand the pilot OSS trajectory, the appointment scheduling system has to be re-designed which allows for a greater group of patients receiving a same-day access, while at the same time respecting the conditions as set by the One Stop Shop project group.

2.1.5 Relevance of the problem

The One Stop Shop concept can be seen as an individual clinic’s service providing a same-day concept to patients. However, on a higher aggregation level it can be seen as an attempt to integrate individual healthcare activities within the hospital.

Professionals in healthcare organizations commonly operate in isolation. Due to developments in society, healthcare organizations are being forced to integrate healthcare activities, thereby focusing on a more patients-central approach (Van der Bij, Dijkstra, De Vries, & Walburg, 1999). Recently, initiatives such as clinical pathways, in which care processes are made more transparent and organized around patient’s needs, are therefore being deployed (Moeke & Verkooijen, 2010). Visser (1999) characterizes patient logistics as the operational control of the chains of activities required for a patient’s care. The chain should be organized in such a way that the quality requirements concerning the provision of services are fulfilled as well as that the available resources are used as efficiently as possible. Integration of individual healthcare activities however is not easy to accomplish. Several reasons can be applied for this, with different stakeholders having different (conflicting) interests being one of them. However, by considering healthcare activities as a process, or a chain of activities, it is seen that there is much to improve within hospitals (Van der Bij, Dijkstra, De Vries, & Walburg, 1999). An example of such improvement is the structured care methodology of clinical pathways (Vanhaecht, de Witte, & Sermeus, 2007).

With integrating healthcare activities being a complex matter, the One Stop Shop trajectory can be seen as a first step in achieving an integration of healthcare activities. Therefore it is a relevant problem to take research upon.

2.2 Scope

Figure 2.2 shows a process overview which places the Pre-operative clinic within the flow of activities a patient proceeds through, from the perspective of the Pre-operative clinic. This is the flow of activities for a patient, under elective circumstances, being referred to a non-contemplative specialism13.

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Figure 2.2 An overview model of a patient flow through the hospital, from the perspective of the Pre-operative clinic

The process begins with a flow of incoming patients. After patients are referred to a physician, in general by their general practitioner, not all patients will proceed for a surgery at the Operating Rooms. Some patients do not require surgery at all, while others can be treated at the policlinic. It can take several appointments with the physician in order to conclude whether a surgery at the Operating Rooms is required. Furthermore, from the perspective of the Pre-operative clinic, whether a physician has a consultation hour has an important impact on the flow of referred patients to the Pre-operative clinic; when a physician does not have a consultation hour, it is certain that an amount of zero patients are referred.

Patients who have to undergo a surgery at the Operating Rooms can be categorised in three different groups: elective, urgent and emergency patients (Gupta & Denton, 2008). Elective patients can be scheduled in advance. Emergency patients require surgery within a few hours to days, and most of the time are not referred by a physician, but arrive per ambulance. Urgent patients are equal to elective patients although their medical urgency constrains the timespan in which the surgery has to occur. Another distinction in patients can be made between ambulatory and not ambulatory patients (Cayirli & Veral, 2003). Both ambulatory and non-ambulatory patients have to receive a pre-operative screening before they can be scheduled for a surgery. For non-ambulatory and emergency patients however, the anaesthesiologist ‘visits’ the patient. These patients are not scheduled for a pre-operative screening at the Pre-operative clinic and therefore fall outside the scope of this research. All other groups of patients, under the condition that the anaesthesiologist is responsible for the anaesthesia of the patient during the surgery14, do receive the pre-operative screening at the Pre-operative clinic and are included in the scope.

The WZA’s physicians of each specialism are not in employment, but operate in partnerships. In a large corporation, there is a typical chain of command, the system of hierarchical reporting relationships (Jones, 2007). Jones (2007) defines a hierarchy as “a vertical ordering of organizational roles according to their relative authority”. The physicians of each specialism of the WZA form an

14_{There are surgeries at which the anaesthesiologist is not responsible for the anaesthesia. This is explained in}

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exception to this standard. Most physicians of the WZA’s specialisms are gathered in partnerships, with anaesthesiology being one of the exceptions. At a strategic level the partnerships have a contractual agreement (regarding for instance the levels of production) with the WZA, but at an operational level they are free in their realization.

The partnerships have the effect that the physicians are completely autonomous in their operational management. However, as is seen in Figure 2.1, especially with a same-day service, the arrival rate of patients is a function of the agendas of the supplying physicians. Acknowledging that there is no hierarchical relationship on behalf of which the actual agenda can be influenced, the scheduling of the different specialisms should partially be included in the scope. Appendix 2 provides more details about these partnerships and the inexistence of a hierarchical relationship between the specialisms and the hospital organization.

During the pre-operative screening, the anaesthesiologists can ask for an additional consult from a different specialism (for instance cardiology) before conducting or concluding the pre-operative screening. The scheduling of these additional consults does not take place at the Pre-operative clinic and therefore falls outside the scope of this research. It should be noted that for the One Stop Shop trajectory, patients requiring additional consults, by definition do not get access to the One Stop Shop trajectory. This is because these additional consults require the patient to visit the hospital again on a different day.

After receiving a positive conclusion of the pre-operative screening, the patient’s surgery can be scheduled. The succeeding planning processes for the Operating Theatres, as well as the Aftercare phase, fall outside the scope of this research.

2.3 Stakeholder analysis

When conducting a research, analysing which parties are involved is an important matter; some parties will have an influence on the research itself, others will be affected by its outcome. Gardner, Rachlin, Sweeny, & Richards (1989) developed the Power-Dynamism matrix, which is shown in Table 2.1. The matrix shows how to handle specific stakeholders based on their power and level of interest.

Level of interest Power

Low High

High Keep satisfied Key players Low Minimal effort Keep informed

Table 2.1 Stakeholder analysis, adopted from Gardner, Rachlin, Sweeny, & Richards (1989)

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Stakeholder Role Interest Power Level of

interest

(Assistant)-anaesthesiologists

Performs the pre-operative screening - Workload - Overtime - Utilization of POC - Predictability of clinic’s schedule High High

Admission department Schedules patients within the available ORs - Mix of schedulable patients Low Low Management team Care Coordinator of the Care departments - Utilization of POC - Access time of POC

High High

Operating Room staff Performs & assists at surgeries

- Workload - Overtime

- Utilization of ORs

Low High

Patients Require surgery - Access time - Waiting times - Accessibility OSS

Low High

Project group OSS Responsible for the OSS project

- Utilization of POC - Access time of POC - Accessibility OSS

High High

Contemplative specialisms

Refer patients to the ORs and thereby to the POC

- Available POC capacity

- Access time of POC - Waiting list size - Utilization of available OR capacity - Accessibility OSS High High Secretary Pre-operative clinic

Performs the POC’s front- and back office administration

- Workload - Overtime

Low High

Table 2.2 Overview of stakeholders, their roles and interests, and the assigned score in the Power- Level of interest matrix

The overview shows different equivalent interests and some contradictory interests. The Pre-operative clinic’s utilization can be seen as equivalent with the available Pre-Pre-operative clinic’s capacity for the specialisms. The interests of the One Stop Shop project group, as already explained in Section 2.1, could be seen as the most contradictory: utilization and access time of the Pre-operative clinic.

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Figure 2.3 Visualization of the stakeholder analysis with the Power – Level of interest matrix

Figure 2.3 show that the majority of stakeholders have a high level of interest, with an almost equal division between stakeholders having a low and high power categorisation. Therefore, the outcome of the research has to be reflected upon a large portion of the stakeholders. The elaboration on the different stakeholders and the reasoning behind their scoring can be found in Appendix 3.

When regarding the different interests, several interests seem to be the most important. The utilization of the Pre-operative clinic is seen as important by different stakeholders, as it determines the cost-effectiveness of the clinic as well as the workload for the clinic’s staff. The clinic’s access time is a determinant of the effectiveness of the relation between supply and demand, with a high access time suggesting a mismatch in this relation, and is a good determinant for the patient’s service level for non-OSS patients. Finally, the accessibility for OSS patients is seen as important. With the OSS trajectory being seen as a distinctive capability of the hospital compared to other healthcare providers, the actual accessibility for OSS patients reached determines the effectiveness of the distinctive capability in practice.

2.4 Problem statement

With the problem being described, the setting of the scope and its environment and the evaluation of the (direct) stakeholders and their most important interests, this section formulates the research objective and question.

The problem analysis in Section 2.1 revealed two problems. First, it is required to re-design the Pre-operative clinic’s appointment scheduling system in order to allow for a greater group of patients receiving a same-day access to the pre-operative screening. Second, with the re-design the conditions as set by the One Stop Shop project group, and the interests of the different stakeholders, should be respected, without sub optimizing between different groups of patients, i.e. between OSS and non-OSS patients. The most important interests where the clinic’s (variation in) utilization, patient’s access time and the One Stop Shop accessibility. As the last two interests both are

Power

Level of interest

Patients Management team Care Secretary Pre-operative clinic (Assistant)-anaesthesiologists Contemplative specialisms Operating Room staff Admission department Project group OSS

Keep satisfied Key players

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applicable to patients and their perspective of received service, they are combined in the term patient’s service level.

The research objective for this research therefore is stated as:

RESEARC

H

OB

JECT

IVE Design and test an appointment scheduling system for the WZA’s Pre-operative clinic that allows for an expanded same-day service, reaching an optimal service level for patients while sustaining a low variation in the clinic’s utilization.

In order to reach the research objective, the following research question is formulated:

RESEARC

H

QUESTI

ON How can the service level for patients of the WZA’s Poperative clinic be increased by re-designing the appointment scheduling system, allowing for an expanded same-day service while sustaining a low variation in the clinic’s utilization?

2.5 Conceptual model

Figure 2.4 shows a graphical representation of the concepts and assumed relations between the concepts, relevant for answering the research question: the conceptual model.

Figure 2.4 Conceptual model

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2.5.1 Operationalization of variables

Demand for care consists of all ambulatory elective patients who have to receive a pre-operative screening. Within the group of patients a trichotomy is made between regular, urgent and One Stop Shop patients, as explained in Section 2.2. On a specialism’s level, the arrival rate between individual patients is measured as the number of patients being referred to the Pre-operative clinic per unit of time, in line with the definition of Hopp & Spearman (2008).

Pre-operative clinic’s resources consist of the composition of the medical staff consisting of anaesthesiologists, nurse anaesthetists and the secretaries performing the required front- and back office. The number of available consulting rooms is fixed at ≤ 3 and the opening hours are from 08.00 – 17.00 hours, in which the available scheduling hours depend primarily on the duration of intermediate breaks.

Service level can be defined as the extent to which delivery promises are kept, thereby honouring the delivery time given to the customer (Slack & Lewis, 2002). For this research, this is translated in the two types of access delays a patient faces: virtual- and captive waiting time (Gupta & Denton, 2008). Virtual (or indirect) waiting time is the difference between the request for an appointment and the actual date of the appointment itself, and is measured as the number of days after which the first available appointment slot for the patient is. Captive (or direct) waiting time is defined as the difference between the time of a requested appointment and the time at which the patient is actually served by the ‘provider’. Note that the time a patient is waiting due to an early arrival thereby is not taking into account in the calculation of captive waiting time.

As can be seen in Figure 2.4, service level is split up in two components: accessibility for One Stop Shop patients and virtual waiting time for non-OSS patients. One Stop Shop patients should receive an appointment on the same day, which results in a virtual waiting time being less than one day. However, the set conditions state that a percentage of OSS patients should receive the same-day access, which cannot be accurately measured by averaging the virtual waiting time for OSS patients. Therefore, the percentage of OSS patients actually receiving an appointment on the same day is measured, which is referred to as the accessibility for OSS patients. The terms accessibility for One Stop Shop patients and OSS patient’s service level are used alongside each other. The term accessibility is especially used when the distinction between OSS and non-OSS patients has to be made clear. With regard to captive waiting time, there is no difference between both groups of patients.

Utilization refers to the amount in which a resource effectively is used. Analytically it is described as the product of the average arrival rate and the effective process time (Hopp & Spearman, 2008). Translated for this research, utilization refers to the occupation of the Pre-operative clinic’s schedule, which is measured on a daily basis15. As the amount of patients receiving a pre-operative screening is dependent on the referring specialisms, the utilization levels primarily can only be influenced by the amount of available capacity. In order to control the stability of the appointment scheduling system,

15_{The alternative is to measure the -average- utilization level over a period. As the clinic’s opening times are}

rather strict and working overtime is merely being done in exceptions, a low utilization level on day cannot be recovered by a higher utilization level on day . Using a daily measure for the utilization level

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the daily variation in the utilization level is added as a component, i.e. preventing that some days are fully occupied, while other days remain empty.

2.5.2 Research questions

Based on the conceptual model presented in the previous paragraph, six sub questions are created which are used to answer the main research question, categorised in three subjects:

Description of appointment scheduling systems 1. What is an appointment scheduling system? 2. What ‘One Stop Shop’ variations exist in literature? Analysis of the current situation

3. How is the Pre-operative clinic organized in order to fulfil the demand for care?

4. To what extent does the Pre-operative clinic currently reaches the set performance criteria? Designing the appointment scheduling system

5. Which actions can be devised in order to increase the patient’s service level while remaining a high and constant utilization level?

6. What is the effect of the proposed actions on the performance measures utilization and service level?

In general, the description of the appointment scheduling system is discussed in Chapter 3, the analysis of the current situation in Chapters 4 and 5 and the re-design of the appointment scheduling system is treated in Chapter 6.

2.6 Methodology

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Figure 2.5 Regulative cycle adopted from van Strien (1997)

The aim of this research is to design and test an appointment scheduling system for the WZA’s Pre-operative clinic that allows for an expanded same-day service, reaching an optimal service level for patients while sustaining a low variation in the clinic’s utilization. In order to achieve this goal, the first two phases of the regulative cycle are treated in detail. By testing the appointment scheduling system, to a certain extent the implementation phase is also treated. The discussion chapter at the end of this research provides for the evaluation phase.

In order to answer the research questions and perform the research, several sources of information are consulted: relevant literature is used as a basis with interviews providing additional and practical information. These sources are supplemented with existing WZA documentation concerning the topic. Besides a thorough qualitative analysis, this research attaches much importance to an analytical analysis. The dataset required for the analyses is retrieved from the WZA’s main information system: EZIS (Electronic Hospital Information System). EZIS is a package in which all essential hospital information is stored: from patient’s medical information to nursing information, from patient records, policlinic appointments and admissions to Operating Room information. Although EZIS is one package, it uses different modules, which are not directly interchangeable. The data from the different modules therefore have to be combined in order to create the dataset required for this research. In order to do so, the data from the different modules in compiled into a MySQL database. The dataset in this research is constructed from the first six months of 2011, consisting of all surgeries (6.354 surgeries), the patient’s waiting lists for surgeries (354) and the policlinic agendas of all 8 non-contemplative specialisms (61.960 appointments). This is extended with a dataset concerning a classification of a patient’s medical condition.

Design

Implementation Evaluation

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Cha pter: Li ter ature review o n appoint m ent sche d ulin g sys tem s

20 3. Literature review on appointment scheduling systems

In this chapter an overview of relevant literature on appointment scheduling systems is provided. In doing so, an answer is provided to sub questions 1 and 2:

1. What is an appointment scheduling system?

2. What ‘One Stop Shop’ variations exist in literature?

The answers on these questions are used to model and analyse the current appointment system in Chapters 4 and 5 as well as to be used as guidelines for the re-design of the appointment scheduling system in Chapter 6. For these reasons, Section 3.1 starts with an elaboration of a framework on appointment scheduling which provides for a structured approach in analysing appointment scheduling systems. Section 3.2 continues with an overview of the relevant literature concerning appointment-scheduling systems. In Section 3.3 Open Access systems are introduced, which deal with the same uncertainty as the One Stop Shop scheduling, as explained in Section 2.1.

3.1 Framework for appointment scheduling

In their analysis of existing frameworks for health care operations management, Hulshof, Van Houdenhoven, & Hans (2011) proposed a revised (modern) framework for health care planning and control, thereby focusing on different managerial areas and hierarchical decompositions. The framework is shown in Table 3.1. Especially the hierarchical decomposition within the ‘resource capacity planning’ managerial area is interesting for this research, as it provides a structured approach in analysing appointment scheduling systems. Therefore, this section briefly describes the ‘resource capacity planning’ managerial area.

Medical planning Resource capacity planning Materials planning Financial planning Hierarc hical decomp ositi on Strategic Research, development of medical protocols

Case mix planning, capacity dimensioning, workforce planning Supply chain and warehouse design Investment plans, contracting with insurance companies Tactical Treatment selection, protocol selection Block planning, staffing, admission planning Supplier selection, tendering

Budget and cost allocation Offline operational Diagnosis and planning of an individual treatment Appointment scheduling, workforce scheduling Materials purchasing, determining order sizes DRG billing, cash flow analysis Online operational Triage, diagnosing emergencies and complications Monitoring, emergency coordination Rush ordering, inventory replenishing Billing complications and changes Managerial areas

Table 3.1 Example application of the framework for health care planning and control to a general hospital (Hulshof, Van

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Cha pter: Li ter ature review o n appoint m ent sche d ulin g sys tem s

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The strategic planning has a long planning horizon and is based on highly aggregated information and forecasts (Hulshof, Van Houdenhoven, & Hans, 2011). These decisions represent long-term managerial decisions and thereby determine the direction in which the organization will proceed. For the Pre-operative clinic, the decision to implement the One Stop Shop trajectory can be seen as an example of such a decision.

In between the strategic level and the operational level, lies the tactical planning level. This also involves decisions on a longer planning horizon, although the horizon is shorter as compared to the strategic planning. The allocation of One Stop Shop slots to the Pre-operative clinic’s schedule, or the construction of a schedule as such, can be seen as a decision on the tactical planning level. It involves managerial decisions which are taken in between the long- and short time horizon.

The operational level is divided in an offline and online part, thereby reflecting decision being made in advance and decision being made as a result of an event, or reactive decisions. The scheduling of patients in the Pre-operative clinic’s schedule is an example of an offline operational action. Given the flow of patients arriving at the Pre-operative clinic, the decision whether to ask for support from the anaesthesiologists at the Operating Theatres in the case of an excess in supply can be seen as an online operational decision.

3.2 Appointment scheduling systems

The actual scheduling of patients in the Pre-operative clinic’s schedule is an example of an offline operational action in the framework of Hulshof, Van Houdenhoven & Hans (2011). In order to be able to schedule patients, first an appointment scheduling system should be present. This section therefore describes an appointment scheduling system.

A healthcare appointment scheduling system can be described as a system used to manage- and schedule appointments for health care providers, for instance physicians. The system is used to allocate appointments to time slots, during a physician’s consultation hours. This allocation is done according to so-called appointment scheduling rules. The objective of healthcare appointment scheduling is trading off the interests of physicians and patients. The interests between both can be different and even contradicting, with patients for instance preferring a short waiting time, and physicians more likely preferring a short idle time, and to finish on time (Kaandorp & Koole, 2007). An appropriate set of scheduling rules should optimize both the interests of physicians and patients. When designing an appointment scheduling system for a hospital’s clinic, the clinic can be regarded as a queuing system, representing a unique set of conditions. The simplest case is when all patients are scheduled, arrive punctually at their appointment times and a single doctor serves them with a deterministic processing times (Cayirli & Veral, 2003). It becomes more complicated when unpunctual patients are present, processing time are stochastic, walk-ins and emergencies intervene and disturbing the schedule or when there is a high percentage of patients ignoring their appointment (no-shows). In their literature review, Cayirli & Veral (2003) discuss several environmental factors for modelling an appointment scheduling system, which also describe these interventions:

i. Number of services; single stage or multiple stage

Appointment scheduling for a hospital’s Pre-operative clinic