Received 18 October 2009; accepted 16 October 2010. Available online 26 October 2010.
Abstract
The European Working Group “Operational Research Applied to Health Services” (ORAHS) is one of the domain specific EURO Working Groups organized by EURO – the European Association of Operational Research Societies. In this paper we report on the development of ORAHS as a platform for OR in health, and analyse the papers presented at meetings over the 35 years of its existence. We propose a two-way framework for analysis, where one dimension is the nine stages of the product life cycle: identifying consumer requirements, designing a new service to meet these requirements, forecasting demand for such a service, securing resources for it, allocating these resources, developing Programs & Plans to use these resources for delivering the service, establishing criteria for service delivery, managing the performance of the service, and finally, evaluating its performance. The other dimension is a three-level classification into broad application areas referring to processes at different levels in healthcare: Patients & Providers, Units & Hospitals, and Regional & National. We use this framework to carry out a quantitative analysis of all the papers presented during the meetings of ORAHS since its inception in 1975. We then describe developments over this period in applying OR approaches and techniques to healthcare, and present an overview of the main application areas and challenges.
Keywords: OR in health services; Applications of OR; Review
1. Introduction
The use of Operational Research in healthcare has developed considerably over the years, for a number of reasons. Healthcare has become a major industry, with many people involved either as employees in healthcare delivery organisations or as consumers of healthcare services. The UK’s National Health Service is actually the largest employer in Europe. The rising costs of healthcare due to new technologies and demographic trends (in particular, the ageing population), is a vitally important issue for healthcare policy makers. At the same time there is a paradigm shift in the service concept of healthcare. Patients are no longer prepared to accept poor quality service, either in terms of long waiting times or inconvenient appointment systems, and expect that services are well organized from a “customer” perspective. The service concept has shifted from optimizing the use of resources to finding a balance between service for patients and efficiency for providers. These developments have had an impact on the popularity of OR in healthcare not only in terms of the number of OR applications but also of the scope of topics covered.
The characteristics of health OR – which make it different from OR in industry or in commercial services – stem from the way healthcare organisations operate and from the type of healthcare system in use in a particular country. A hospital organisation, for instance, consists of units (outpatient departments, wards, operating theatres, etc.) which contribute to the processes delivered by clinical specialties. Hospital management does not always have much control over output, as core processes are often controlled by clinical specialists who in many European countries have a contract with the hospital but are not salaried. Therefore, the line of command structure in hospitals is not always straightforward. Decision making is carried out in more of a political arena in which the interests of different stakeholders need to be balanced. Standardisation of product and process is difficult due to the high variation between hospitals and also between clinicians within the same specialty. Moreover, medical professionals want to keep their autonomy in the care delivery process. Although doctors manage the clinical process, and nurses the nursing process, no one is in charge of the customer process as a whole.
The healthcare system in use in a given country is another important influential factor in the healthcare industry. Healthcare systems vary between countries in terms of their incentives for reducing waiting lists or controlling the costs of care. Countries with a healthcare system with more market competition tend to put more effort into service improvement, whereas countries with a budgeting system put more emphasis on improving efficiency. This paper focuses on European healthcare systems, which typically provide coverage of most healthcare costs for all inhabitants and enable the costs of healthcare expenditure to be controlled at a national level. This is also true of the healthcare systems in a few countries outside Europe, such as Canada and Australia.
This review is largely, but not exclusively, based on material from papers presented in meetings of the European Working Group Operational Research Applied to Health Services (EWG ORAHS) in the years 1975–2009. The EWG ORAHS is one of the domain specific Working Groups linked to EURO, the European Association of Operational Research Societies. This material is used as empirical evidence for the interest of OR in health care issues, and is the basis for a statistical analysis of the development of the field over time.
OR in health is first and foremost applied OR with a major emphasis on implementation. Applications are often the result of collaboration between practitioners and academics. Meetings of ORAHS always involve interaction with practitioners. For this reason, this paper does not use techniques (scheduling, simulation, queuing, etc.) as a framework for discussing applications, but it follows a more user-focused perspective. The framework used is based on a combination of a product life cycle perspective and the level of decision making that is supported. The use of a product life cycle perspective for defining application areas of health OR was first suggested by Royston (1998). With some minor adjustments to Royston’s schema, the following stages of developing and managing a service can be identified:
1. identifying consumer needs for health services,
2. developing a new service to meet those needs,
3. forecasting the demand for services,
4. securing resources for delivering services,
5. allocating resources for delivering services,
6. developing programs and plans that will use these resources in delivering services,
7. developing criteria for delivery performance,
8. managing the performance of delivery,
9. evaluating the results of healthcare delivery.
The level of decision making is defined as the levels in the healthcare system at which the process and operations considered take place ([Vissers, 1998a] and [Vissers, 1998b]), namely:
– processes and operations at individual patient or provider level,
– processes and operations at the level of a unit (outpatient department, ward, operating theatre) or a hospital,
– processes and operations at regional or national level.
A two-way combination of these perspectives, as illustrated in Fig. 1, is used to analyse the application of OR as presented in ORAHS meetings.
Fig. 1.
Application areas of Operational Research in health care.
This framework allows an examination of applications of OR in the different stages of developing and running a healthcare service, in the processes at the level of patients and care providers, the level of units in a hospitals or the hospital as a whole, and at the level of decision making on healthcaredelivery at regional and national level.
The remainder of the paper will be structured as follows. Section 2 contains background information on the EWG ORAHS, its history, objectives and meetings. It also contains the results of the analysis of papers presented at ORAHS meetings since its inception in 1975, and on the profile of ORAHS compared with the wider academic literature on health OR. Some general conclusions are drawn on the development of OR applications in health. In Section 3 we discuss some of the challenges for OR in health in future. Section 4 provides conclusions and recommendations.
2. Development
2.1. ORAHS
ORAHS was founded in September 1975, the same year that EURO held the first European Congress on Operational Research, in Brussels. EURO created a number of European Working Groups in addition to ORAHS. The first meeting of ORAHS was held in Exeter, UK, and was attended by 14 representatives from six countries. Reviews of OR applications related to the healthcare system in each of these countries was a logical start for EWG ORAHS. The profile of its attendees was, and still is, a mix of academics interested in applying OR in health, and OR practitioners working in healthcareas management consultants or managers, sharing as a common feature a dedication to healthcare management.
In this first meeting three main objectives or roles for the working group were proposed, namely: (1) the coordination and dissemination of information concerning health OR work in Europe, (2) the organisation of European seminars on specific health OR topics, (3) the setting up of joint European health OR projects. We will reflect on the development of these objectives over time at later stages of the paper.
One of the first activities was setting up a membership list and a register of OR applications in each of the participating countries. An important decision on the format for ORAHS meetings was taken early on, in the 3rd meeting. Unlike many other EWGs, ORAHS decided that the group would meet separately from EURO meetings in order to provide a more informal, discussion orientated setting which was also more welcoming for health OR practitioners than a mainstream OR conference. This also enabled the local organiser of a meeting to tailor the meeting to the needs of their own national healthcaresystem. Furthermore some general principles regarding future meetings were agreed: (1) to limit the number of attendees to a maximum of about 30, in order to preserve the informal, discussion-orientated nature of meetings, (2) to provide more time for presenting (20–30 minutes) and discussing a paper (15 minutes), (3) meetings to consist of about three working days with a break for social activities in the middle, to encourage partners and families to attend. Although these principles have not always strictly been adhered to, they always have distinguished ORAHS as ‘research family’ meetings from the bigger EURO meetings.
During the early meetings of ORAHS there was much discussion on the identity of OR and the extent to which it overlapped with neighbouring disciplines such as health economics or medical statistics. After a few meetings in which part of the meeting was devoted to, for instance, health economics, these boundary issues were further explored, resulting in a clearer focus on health OR. The development of joint projects turned out to be a difficult issue. Apart from exploring potential themes (disease prevention, primary care, screening) the group never successfully achieved a joint project involving several participating countries. More successful modes of collaboration included publishing books and organizing sessions for healthcare managers on applying OR in healthcare management and planning. One of the earliest examples was the publication of ‘Operational Research Applied to Health Services’ (Boldy, 1990).
The first self-evaluation was performed in 1983 based on a questionnaire among members. As a result the application oriented profile of ORAHS, and the informal style of meeting separately from EURO were reconfirmed. A few proposals were made to create more structure: a register of members, a newsletter, proceedings of meetings – although this latter suggestion was felt to be somewhat over-ambitious at the time. The first proceedings of an ORAHS meeting was produced by Kulej et al. (1991) when the group met in 1990 in Wroclaw, Poland. From 1995 onwards, publishing proceedings of meetings became standard ([Kastelein et al., 1996], [Matson, 1997], [De Angelis et al., 1999], [Mikitis, 2000], [Riley, 2001], [Rauner and Heidenberger, 2003], [Ferreira de Oliveira, 2004], [Dlouhy, 2004], [Lagergren, 2006], [Brailsford and Harper, 2007a] and [Xie et al., 2009]). Occasionally this was combined with Special Issues of scientific journals, for example the European Journal of Operational Research ([Schreuder, 1987], [Delesie et al., 1998]and [Rauner and Vissers, 2003]), the Journal of the Operational Research Society ([Davies and Bensley, 2005] and [Brailsford and Harper, 2007b]) and Health Care Management Science (Dexter et al., 2009).
One or two day workshops with healthcare managers started in 1984 as part of the meeting in Altavilla, Italy. Standalone workshops were held in 1987 (Leeds, UK), 1990 (Wroclaw, Poland), 1991 (Veldhoven, The Netherlands), and 2000 (Sydney, Australia). The programme of these workshops was aimed to offer OR support to practitioners in managing healthcare systems. The lectures were given by members of ORAHS.
Trends in the numbers of participants, countries and papers over the period 1975–2009 are shown in Fig. 2.
Fig. 2.
Number of participants, countries and papers at ORAHS meetings 1975–2009.
In the period between 1975 and 2000, the meetings show a stable attendance pattern with about 25–40 participants, 10–14 countries represented and 15–25 papers presented. From 2000 onwards a remarkable increase in the number of attendees can be seen. A new pattern of meetings seems to be emerging: larger meetings with 80–150 participants, more international and global participation, and a larger number of papers. Moreover, a larger proportion of attendees did not present a paper. How can this be explained?
The reason was the concern for a number of years in the period up to 2000 about the growing average age of the participants. ORAHS members were studying the increasing healthcare costs due to an ageing population, while they themselves were growing old! Therefore in order to address this problem and introduce new blood, MSc and PhD students were invited to meetings, and in 2005 a European Summer Institute in “OR in health” was held in Southampton prior to the main ORAHS meeting. About 30 PhD students and early career researchers from all over Europe (and beyond) participated in a meeting with tutorials on various subjects by senior researchers and presentations by PhD students. The rapid increase in PhD student numbers in health OR is another sign of the popularity of health OR, but of course may also reflect a general trend of increasing numbers of PhD students. The larger scale of the meetings has put some pressure on the traditional ORAHS format of meetings, as informal discussion is less easy with larger numbers of participants. Moreover the PhD presentations tend to put more emphasis on theoretical developments rather than practical implementations. Time will tell whether ORAHS has gained an increase of younger colleagues at the expense of decreasing participation of OR practitioners, and this is one of the challenges ORAHS has to face.
In the following sections, we compare the work presented at ORAHS meetings with the general health OR academic literature.
2.2. The profile of ORAHS and health OR
The academic literature on healthcare modelling is vast, and is growing at an astonishing rate. Searches carried out on several consecutive days using the Web of Knowledge bibliographic database (wok.mimas.ac.uk) and the search string “((healthcare or healthcare) and (modelling or modelling or simulation))”, was found to be expanding at the rate of about 30 papers a day. It is hard to believe that any individual could keep abreast of such a literature or undertake a systematic review of it. Nevertheless, in the past few decades, many review papers have been written about the use of modelling in healthcare. As this is such a vast topic, these reviews have generally focused either on a specific modelling approach, such as discrete event simulation (e.g. Fone et al., 2003) or on the use of modelling for a specific healthcare setting, such as clinics (e.g. Jun et al., 1999).
Fries (1976) published one of the first international reviews of healthcare modelling. This appeared in the US journal Operations Research in 1976 – one year after the inaugural ORAHS meeting. This review categorised the 188 papers it included by application area, for example appointment systems, demand forecasting, ambulance deployment, and health planning. Fries subsequently augmented this with a further 164 papers (Fries, 1979), covering most of the mainstream OR journals up to 1979, and it is likely that the 352 papers it includes represent most of the health OR literature at that time. A review paper on computer simulation studies was published shortly afterwards by Wilson (1980), covering over 200 papers. A follow-up paper (Wilson, 1981) focused on implementation issues, since only 16 of the 200 papers reported recommendations that had been acted upon.
One of the most highly cited papers in the healthcare literature, Jun et al. (1999), is a survey of the application of discrete event simulation modelling to healthcare clinics, for example hospital outpatient clinics and emergency departments. This review covered the previous 20 years and categorised papers under two main themes: patient flow and allocation of resources. More recently, Fone et al. (2003) produced a systematic review of discrete event simulation modelling in population health and healthcare delivery. The authors comment that although the number of modelling papers has grown substantially in recent years, very few papers report on outcomes of implementation of models and so the value of simulation modelling requires further research. It is somewhat depressing to observe that little appears to have changed since Wilson made the same comment in 1981.
Finally, the UK’s RIGHT project (Research into Global Healthcare Tools, www.right.org.uk) included as one of its outputs a multi-dimensional analysis of the research literature on simulation and modelling in healthcare (Brailsford et al., 2009). The aim of RIGHT was to assess the feasibility of applying to decision-making in healthcare some of the modelling and simulation methods used to support decision-making in other sectors, such as manufacturing industry and defence. Part of the research involved an analysis of the relative frequency of use of a range of Operational Research modelling approaches in healthcare, along with the specific domains of application and the level of implementation. To deal with this massive literature, it adopts a novel methodology, similar in concept to the approach of stratified sampling. A final sample of 342 papers were chosen, representing not the “best” 342 papers in OR in health, but rather the general profile of this body of literature as a whole. The study still reported overall a lack of implementation as demonstrated by the literature, although in the UK as probably elsewhere, much modelling is being undertaken by business consultancies and appears only in the “grey” literature.
In summary, most of these previous reviews have limited their scope either by focussing on simulation (in particular discrete event simulation) or by focussing on specific application areas while including a broader range of OR approaches. Likewise, this current review adopts a similar approach to scope reduction, by focusing on the work of the European Working Group ORAHS. However, we will contrast our findings with these other reviews, in particular by considering whether ORAHS papers have any kind of distinctive features or characteristics which mark them out as different from the “mainstream” health OR literature. We shall contrast the ORAHS papers with the RIGHT papers, insofar as this is possible, using the same dimensions which were used in the RIGHT review. Apart from the practical problems of the magnitude of the task of analysing all the papers presented at ORAHS since its inception in 1975, a limitation of this numerical comparison is that this detailed analysis was only possible for a few of these 34 years, as full versions of the papers presented (or in some cases, even abstracts) were not always available. We therefore present results for three selected periods: 1975–1980, 1996–2001, and 2008, a total of 233 papers.
2.2.1. The RIGHT review
The fields considered included: modelling method, initiators (academia or healthcare), funding source, level of implementation, functional area, industry layer (strategic, tactical, or operational), country, and year of publication. Methods were broadly characterised as qualitative modelling (e.g. cognitive modelling, process mapping); statistical and regression analysis; statistical modelling (Markov models, structural equation modelling); simulation (discrete event simulation, system dynamics, Monte Carlo simulation) and spatial modelling. Functional area was defined as follows:
1. Finance, Policy, Governance, Regulation.
2. Public Health, community service planning.
3. Patient behaviour/characteristics.
4. Planning, system/resource utilization.
5. Quality management, performance monitoring or review.
6. Risk management, forecasting.
7. Workforce/staff management.
8. Research.
9. Other.
2.2.2. Comparison of RIGHT with the ORAHS papers
One might hypothesise that ORAHS, because it involves practitioners in its meetings, might report a higher implementation rate for its models than the general literature. This was found to be the case, as Fig. 3 shows, but the difference was not striking, and even ORAHS shows a depressingly low implementation rate (just over 6%). “Suggested” means that the studies were carried out in collaboration with a health care organisation, but no practical implementation was reported, and “Conceptualised” means the study was carried out solely by academics with no input from healthcare practitioners. Surprisingly, a higher proportion (50%) of ORAHS papers fell into the “Conceptualised” category than was the case in the general academic literature (45%).
 |
Fig. 3. Level of implementation (N = 342 (RIGHT), N = 233 (ORAHS)) |
In terms of industry layer, there is a significant difference between ORAHS and the general literature as represented by RIGHT. In Fig. 4, the strategic planning level is denoted as “Policy or Regulation”, the tactical level as “Facilitation or Commissioning”, and the operational level as “Operation”. Over 60% of ORAHS papers were at the most detailed operational level, compared with around 40% in RIGHT. This no doubt reflects the general tendency of “traditional” mathematically-oriented Operational Research to be applied to operational, rather than strategic problems. The RIGHT papers covered a broader range of modelling, across a variety of OR disciplines, including (but not limited to) mathematical OR. On the other hand, ORAHS members are predominantly mainstream traditional OR researchers, and this is reflected in the greater number of detailed operational models.
Fig. 4.
Level at which modelling was used (N = 342 (RIGHT), N = 233 (ORAHS)).
This argument is borne out by the analysis of the modelling methodology adopted. In the overall broad categories shown in Fig. 5, by far the largest category in the ORAHS data is “mathematical models”, which account for around 31% of the sample. In the general RIGHT data, less than 10% of papers fall into this category. However, statistical studies, which together comprise over 56% of the general healthcare modelling literature, only form about 22% of the ORAHS data. There are more simulation studies in ORAHS than in the general literature, and also, more qualitative modelling studies. One possible reason for this is the popularity of these particular approaches in the UK, which is recognised for its strength in “soft OR” (EPSRC International Review, 2004) and the high proportion of ORAHS studies based in the UK.
Fig. 5. Methodology by broad category (N = 342 (RIGHT), N = 233 (ORAHS)).
Fig. 6 depicts the functional area within the healthcare system for which the model was developed. Clearly, there is a strong tendency for ORAHS studies to be mainstream applications of OR modelling to the established areas of capacity planning and resource utilisation. Over 36% of ORAHS studies fell into this category. This was also the largest single category in the general literature too, but it contained only around 20% of papers in the RIGHT survey.
Fig. 6, Application to functional area (N = 342 (RIGHT), N = 233 (ORAHS)).
2.3. Statistical analysis of ORAHS papers
This section contains an analysis of all the papers presented at ORAHS meetings from 1975 to 2009, concentrating on papers presented orally rather than on those published in proceedings. The reason for this was that in the early years proceedings were not produced, and in later years not all presented papers were included in the proceedings. Therefore the focus is on the topics presented and discussed in the meetings. Bearing in mind the topics of the papers, they were categorised according to the two-dimensional model introduced in Section 1: the stages of developing and managing a service, and the level at which the process is taking place. This structure was purposely chosen in order to emphasise the use of OR in healthcarepractice, rather than focusing on specific modelling techniques.
This was not an easy task, as sometimes the only available information about a paper was the title, or occasionally the abstract, listed in the meeting programme. To limit interpretation bias, both authors checked every paper. Some examples of the interpretation difficulties were:
– Should a survey on patient opinions of care delivery be classified as performance evaluation, or the identification of consumer requirements?
– Is developing a new way of scheduling patients, with consequences for resources, resource allocation or developing a planning system?
– Is benchmarking performance part of routine performance management or performance evaluation?
– Is a care pathway always Patient & Provider level, or can it also be national level when used for developing national guidelines?
It can easily be envisaged that many such practical problems of this nature had to be overcome in the task of categorizing more than 1100 papers.
2.3.1. Results
The total number of papers presented during ORAHS meetings between 1975 and 2009 was 1115. One hundred and forty-five papers were excluded from the analysis as these were mainly review papers, either discussing a country’s healthcare system and the challenges for OR, or were a purely theoretical or methodological paper that did not fit into the categories of the framework used for analysis. Table 1 shows the overall distribution of papers by category of service stage and process level. The whole period 1975–2009 was broken down by decade into four periods 1975–84, 1985–94, 1995–2004 and 2005–09
It can be seen from Table 1 that all levels are substantially represented, but Regional & National level (33%) and Unit & Hospital (42%) occur more frequently than Patient & Provider (25%). The number one position of Unit & Hospital is not surprising as OR applications often are associated with tactical planning, which is more or less similar to the Unit & Hospital level.
In terms of the distribution of papers over the stages of developing and managing a service, it can be seen that the majority of papers fall into categories 6 (Programming & Planning), 8 (managing performance) and 9 (evaluation). It is noticeable that three categories, 1 (identifying consumer requirements), 2 (developing a new service) and 7 (performance criteria) contained hardly any papers. An explanation for this could be that operational researchers are traditionally less involved in service innovation, and that performance criteria are likely to be included in papers on managing or evaluating a service.
Within the different service life cycle categories, it can be seen that in 1 (consumer requirements) and 2 (developing a service), papers are (logically) concentrated mainly at the Patient & Provider level, whereas categories 3 (forecasting), 4 (securing resources) and 5 (allocation) are focused at the Regional & National level, and categories 6 (Programming & Planning) and 8 (managing performance) are mainly concentrated on the Unit & Hospital level. However category 9 (evaluation) is equally divided between all three levels.
Fig. 7 depicts trends in the number of papers in the different levels of the healthcare system, broken down over the four decades of analysis.
Fig. 7. Number of papers per period for system levels.
It can be seen that there has been a noticeable trend over time in terms of the level of the system being modelled. There is a sharp increase in the number of papers at the Patient & Provider level and at the Unit & Hospital level, while the number of papers at the Regional & National level stabilises. The combined effect results in a sharp decrease in the proportion of papers at the Regional & National level. These trends are most striking in the change from 1985–94 to 1995–04, where Regional & National loses the number one position (permanently) to Unit & Hospital. A possible explanation for this trend is the increasing popularity of using OR/OM in managing patient flows and resources in hospitals and in making health services delivery more patient centred.
Fig. 8 gives an overview of the trends in papers by life cycle stage over time. A steep increase in recent years in the proportion of papers on managing performance can be seen, while there was a turning point in the number in papers on Programming & Planning after 2004. The increased prominence of managing performance might be explained by the general upward trend in the need to contain the costs of health services, combined with increased demand and higher service expectations.
Fig. 8. Number of papers per period, by life cycle stage.
2.3.2. Trends by life cycle stage
We now discuss trends in the ORAHS papers over time, broken down by service life cycle stage. To limit the length of the paper, stages will sometimes be combined, and only those stages with significant numbers of papers will be discussed.
1. Identifying consumer requirements/2. Developing a service: The first two stages of the life cycle are concerned with identifying the requirements of potential service users and then actually developing the new service. Ideas for a new service are sometimes prompted by patient surveys on existing care delivery, but often also by developments in medical technology. For example, the idea of “advanced access” to tackle the common patient complaint about long waiting times, or starting a specialised clinic for an emergent health problem.
It can be seen from the data in Fig. 8 that this is not a particularly active area of OR research. This can be largely explained by the fact that other disciplines such as Marketing or Psychology are more likely to be involved to investigate the potential of a new service and to ask potential service users what they would consider important for making a service attractive. The development of the service is often an operational activity in which care professionals and managers have a dominant role without much analytical support. Nevertheless, this could be an interesting area for OR, as involvement with starting up an innovation creates many follow-up opportunities for OR contributions, in particular using the more participative approaches of “soft” OR such as cognitive mapping, Soft Systems Methodology or Strategic Options Development Analysis. There is clearly scope for further work in this area, using methodologies which enable different (and possibly conflicting) stakeholder viewpoints to be included in the analysis.
Topics which have been studied in this area of developing new services by ORAHS researchers are community care (Boldy, 1987), care for the elderly ([Lagergren, 2005] and [Forte and Bowen, 2005]), intermediate services ([Bowen et al., 2005] and [Roe and Beech, 2005]), and home care (Arnaert and Delesie, 2007).
3. Forecasting the demand of services/4. Securing resources: Once a new service has been identified and formulated in terms of the types of resources required, the next stage is to forecast the demand for the new service and to ensure that the necessary resources can be made available for the new service.
Fig. 9 shows how the number of papers has changed over time regarding forecasting demand for a service or securing resources for a service.
Fig. 9. Number of papers per period for the stages ‘forecasting demand’ (n = 52) and ‘securing resources’ (n = 21).
Two distinct trends can be discerned in Fig. 9: a ‘rise and fall’ of papers at the Patient & Provider and Unit & Hospital levels, both peaking in the period 1985–94, and a corresponding inverse ‘fall and rise’ in the papers at the Regional & National level. A likely explanation might be that this actually coincides with general underlying trends: forecasting is no longer a specialised technical area requiring OR expertise, but has become part of the domain of general management techniques supported by IT, and securing resources has by and large been addressed by the development of output financing techniques such as DRG’s.
Topics addressed in this category are the projection of infectious diseases such as AIDS/HIV ([Roberts and Dangerfield, 1990] and [De Angelis, 1998]); the demand for care by elderly (Lagergren, 2005), for renal services (Davies and Davies, 1987), for maternity services (Harper and Winslett, 2006), for emergency services (Brailsford et al., 2004), and for long term care (Desai et al., 2008).
For the development of OR work in this area, it is vital that OR modellers collaborate with public health clinicians and epidemiologists (forecasting demand) and health economics (financial models).
5. Allocating resources/6. Developing plans and programmes: The next two phases in the service life cycle – after demand has been forecast and resources secured – is the allocation of resources to units or providers and the development of plans and programmes to use the allocated resources in a service for patients. As there is a fine line between these two phases – the first is resource allocation at an aggregate level, whereas the second is resource deployment at a more detailed level – we will discuss them under a common heading. Allocation of resources is defined to mean determining the capacity to be made available to a unit or a group of care professionals at an aggregate level to provide this service, for instance the annual assignment of a given number of FTE nurses of various grades to a ward (the “nursing establishment”). Developing plans and programmes is interpreted to mean making more detailed plans on how these allocated resources are actually going to be used on a daily basis in a service, e.g. defining the duty roster patterns for the above-mentioned nurses.
Allocation of resources can be regarded as one of the traditional areas of OR research in healthcare. Fig. 10 depicts the trends over time in the number of papers which fall under the heading of ‘resource allocation’.
Fig. 10. Number of papers per period for stage ‘allocating resources’ (n = 68)
Fig. 10 indicates that resource allocation is mainly concentrated at the Unit & Hospital level and at the Regional & National level. The dominant position of resource allocation papers at the Regional & National level in earlier years has been taken over by papers at the Unit & Hospital level. A possible explanation for this trend is that the move towards more market-oriented healthcare systems in recent years has resulted in less demand for resource allocation research, because the allocation of resources will be a result of commissioning processes between supplier organisations (health authorities, insurance organisations) and provider organisations (hospitals, nursing homes, etc.). The apparent increase in the number of papers on resource allocation at the Unit & Hospital level might be explained by the need to underpin allocation issues at this level with more formalised approaches. It is interesting to note that virtually no papers appeared in this category at the Patient & Provider level prior to 1995.
Topics studied in this category include allocating resources from a regional level to health centres or community care centres; allocating ambulances to stations in a geographical area; modelling medical and nurse manpower planning; allocating resources for specific health services, for instance allocation of blood supply to blood banks ([Blake, 2009] and [Katsaliaki and Brailsford, 2007]; allocating resources to preventive programmes (Lasry et al., 2007); allocating of resources in developing countries (Flessa, 2000) and allocation of resources at national level (Van Zon and Kommer, 1999).
Examples of topics at hospital level are: nursing staff and bed allocation to wards in a hospital ([Vissers, 1998a] and [Vissers, 1998b]); determining the capacity required for an intensive care unit (Ridge et al., 1998), or an intermediate care facility ([Utley et al., 2003a] and [Utley et al., 2003b]); allocation of operating room capacity to surgical specialties (Blake et al., 2002).
Fig. 11 shows trends over time in the number of papers on developing programs and plans for using allocated resources for services.
Fig. 11. Number of papers per period for stage ‘Programming & Planning’ (n = 229).
‘Programming & Planning’ is clearly one of the larger areas for health OR research as the number of papers in this category is about 24% of all papers presented in ORAHS meetings.
Fig. 11 indicates the dominance of the Unit & Hospital level over the past 30 years, with a decrease of papers at the Regional & National level, and a remarkable increase at the Patient & Provider level. The popularity of this issue at unit and hospital level is easily explained, since planning and scheduling services for patients is part of their core process. The growth at Patient & Provider level can be explained by the recent interest in care pathways, reflecting a change in emphasis way from a service focus onto an individual patient focused approach.
Topics covered by ORAHS members at the Unit & Hospital level include: admission policies for hospitals ([Gallivan et al., 2002] and [Vissers et al., 2007]), operating theatre planning & scheduling ([Belien and Demeulemeester, 2007], [van Oostrum et al., 2008] and [Blake and Donald, 2002]), nurse scheduling (Ikegami, 2003), appointment systems ([Brahimi and Worthington, 1991] and [Cayirli et al., 2006]), ambulance scheduling (Andersson and Varbrand, 2007) and so on.
At the Patient & Provider level topics are: balance of care approaches (Forte and Bowen, 1989), radiotherapy planning (Aleman et al., 2009), clinical pathway planning (Van Vliet et al., in press), planning prevention and screening programmes (Harper et al., 2003).
7. Developing criteria for service performance/8. Performance management: The next phase in the service life cycle is to manage the performance of the service, once it is up and running. Obviously, criteria are needed for measuring performance, plus tools and methodology to manage performance. However only 1% of the papers focus on developing criteria. The reason for the low score for this topic is probably the fact that definition of criteria normally forms part of any paper on performance management, and few papers focus solely on developing criteria. The few papers that do are nevertheless interesting as they scrutinize popular criteria used in public debate, for instance on waiting times or prioritising patients on waiting lists. An example is the use of the third available slot for an appointment as a measure for the waiting time for a first visit to an outpatient clinic. Blake and Sangster (2009) have shown that this rule of thumb does not hold.
Managing the performance of a service constitutes a major application area of OR in health. Almost 40% of the papers presented at ORAHS meetings fall into this category. Managing performance covers a broad range of tools and methodologies for running a service and monitoring its performance.
Fig. 12 shows trends in the number of papers on managing the performance of a service.
Fig. 12. Number of papers per period for stage ‘managing performance’ (n = 377).
Three trends can be discerned in Fig. 13: a steady increase (particularly sharp in the most recent period) of papers at Unit & Hospital level, a stable number (and therefore a proportional decrease) at Regional & National level, and a sharp increase at Patient & Provider level. This can be explained by the decentralisation of the management of services in healthcare, the importance of efficiency at unit and hospital level and the increased expectations to show service improvement for patients. Papers at the level of Unit & Hospital are by far most popular, with more than 50% of all papers in this category in the most recent time period.
Fig. 13. Number of papers per period for stage ‘performance evaluation’ (n = 175).
Topics covered by ORAHS members at regional or national level include ambulance services (Lubicz and Mielczarek, 1987), cost containment and monitoring of healthcare expenditures (Dlouhy et al., 2007, managing regional waiting lists (Vissers et al., 2001), managing blood supply (Blake, 2009), nursing resource planning (Lavieri and Puterman, 2009).
Topics covered at unit and hospital level include nursing workload, bed management (Harper and Shahani, 2002), operating theatre management (Blake and Donald, 2002), waiting list management (Blake and Sangster, 2009), managing emergency services (Ceglowski et al., 2007), reducing length of stay (Proudlove et al., 2007), running an outpatient service (Brahimi and Worthington, 1991), improving utilisation of resources ([Utley et al., 2003a] and [Utley et al., 2003b]).
Topics covered by ORAHS members at patient and professional level are: medical decision support and risk assessment for patients (Gallivan et al., 2001), discharge planning (Ketabi and Ajami, 2009), process management and lean management (Young et al., 2004).
9. Evaluation of performance: The last phase of the service life cycle concerns the evaluation of service performance. Fig. 13 shows the trends over time in the number of papers presented during ORAHS meetings over the years.
The data in Fig. 13 show similar trends to the previous stage, performance management, but even more markedly: a proportional decrease at the Regional & National level and increases at the Unit & Hospital and Patient & Provider levels. The number one position of Regional & National in the early years has been overtaken by Patient & Provider and Unit & Hospital.
Topics covered by ORAHS members at regional or national level are: cost-effectiveness of prevention programmes ([Buhaug et al., 1990] and [Davies et al., 2000]), comparing models for quality assurance (Amado and Dyson, 2008), evaluation of healthcare programmes and healthcare policy evaluation (Cooper et al., 2003), the use of efficiency measures in healthcare (Mullen, 2004).
Topics covered at unit and hospital level are: evaluation of IT implementation (Leonard, 2000), evaluation of infection control in a hospital (Sherlaw-Johnson et al., 2007), evaluation of strategies for hospital admission (Vissers et al., 2007), and performance assessment of hospitals with DEA (Dlouhy et al., 2007).
Topics covered by ORAHS members at patient and professional level are: patient attitudes to hospitals (Boldy and Bartlett, 1998), quality of home care (De Angelis, 1998), outcomes of prevention programmes (Rauner et al., 2005), evaluation of care pathways (Van Vliet et al., in press), patient safety evaluation (Ekaette et al., 2007).
3. Challenges
Many challenges have been mentioned when discussing OR contributions to the different stages of the service life cycle in Section 2.3. But one of the key challenges for health OR was already outlined in Section 2.2. Despite the abundance of academic publications, the evident growth in the popularity of health OR as a topic for PhD study, the dramatic increase in attendance at ORAHS meetings, and despite the regular large numbers of health OR presentations at mainstream OR conferences such as EURO-k and INFORMS – despite all these things, the number of actual, documented examples of successful implementations of OR models which have become embedded into practice is very small.
For example, the UK’s Department of Health has an OR Group which has, over many years, done outstanding work, some of which has been presented at ORAHS meetings ([Townshend and Turner, 2000], [Royston, 2006], [Fletcher et al., 2007] and [Royston, 2009]). Therefore, one might reasonably expect OR modelling to be institutionalized and widely used across the whole National Health Service. Unfortunately, this is not the case. Given the size and complexity of the NHS, the largest employer in Europe, there is simply too much OR work than can be done by the Department of Health group alone.
Many NHS organizations have outsourced their OR work to business consultancies, but these firms charge high prices and thus a lot of healthcare modelling work is carried out as research/consultancy projects by academics. Nationally, the UK picture is one of multiple “consultancy” projects carried out by individual academics, published in scientific journals and presented at conferences, but not widely taken up and adopted elsewhere by other health providers.
In most other countries in Europe OR has less tradition and profile than in the UK. OR is being taught at Management Schools and used by consultancy firms for projects. Managers are most of the time not aware of OR, its meaning and its potential. Not having a NHS implies also these countries also lack a central function for promoting use of innovative tools such as OR. We see, however, that universities have discovered that healthcare is an interesting market for research, and have set up research groups for OR/OM in healthcare.These research groups and consultancy firms are developing ties with healthcare organisations in research/consultancy projects.
Part of the problem is the tension between research and consultancy. Of course the origins of OR lie in applying analytical methods to real-world problems, and health OR is very much in this tradition, being strongly rooted in practical applications. There is therefore a fine line between “research” and producing a useful model for a healthcare setting. However academics need to publish in peer-reviewed journals and must therefore demonstrate theoretical or methodological advances. This tends to lead to complex, sophisticated mathematical models which can take years to develop, in stark contrast with the objective of the end-user: a simple, easy-to-use model. Business consultancies do not have this problem, of course. Academics and their healthcare collaborators simply work to different agendas and timescales.
However, in terms of the specific stages of the service life cycle, some clear opportunities for OR can be identified. We have already mentioned the scope for greater use of participative, “soft” modelling approaches in the first two stages, identifying consumer needs and developing a new service. This can only increase as the trend for market-focused provision grows, and the views of potential users become increasingly more important.
But the other stages also offer interesting challenges for OR contributions. In the stages of service performance criteria and performance management, there is the challenge of investigating “rules of thumb” which are in common use in healthcare, but can be shown to be too simplistic to be valid. This applies for instance to the rule of thumb used for target occupancies of key resources such as wards, operating theatres and intensive care. Often a single target is used which is either too high (100% occupancy in nursing homes) or too rigid (90% target occupancy for wards), and these simple rules do not take account of stochastic variation or differences in characteristics between specialties. Developing rules of thumb which are on the one hand easy for management to use but are on the other hand more realistic and show a better fit with reality is definitely an area for contribution by health OR. In addition, developing criteria for measuring performance in healthcare (e.g. better performance indicators such as health outcomes, waiting times and patient satisfaction) or investigating the detrimental effects of using over-simplistic service target criteria (for instance the 4 hours target for Emergency Department waits) offer opportunities for health OR.
In the area of managing patient flows and resources there is a trend towards more whole systems approaches, in contrast with developing models for isolated components of the hospital. Booking systems for outpatient clinics, for instance, are the start of a flow through the hospital. The challenge is to speed up operations in one part of the hospital but also take into account the impacts on the rest of the system.
Healthcare organisations are in transition from a supply orientation to a demand driven focus. The patient process is receiving greater attention as healthcare organisations develop. This offers many opportunities for health OR. Nevertheless, the development of the process concept is still at an early stage, and cannot be compared to the more crystallised forms in industry or other services. Therefore the question of using or implementing OR models requires a different viewpoint. The contribution of OR modelling often lies more in organizing data and offering a systems perspective, than in actual use in planning and scheduling. So OR models often function in healthcare as a learning tool for understanding the effects of variation on performance and developing a systems approach to cross hospital patient flows, which is required for instance for integrating care pathways and patient flow logistics. It may, however, be expected that using OR models for planning and scheduling processes can be more effective once the process concept in healthcare has further materialised.
4. Conclusions
We report in this paper on the development of the European Working Group on Operational Research Applied to Health Services (ORAHS) as a platform for OR in health, and have analysed the papers presented at meetings. We follow a two-way framework for analysis, where one dimension is the nine stages of the product life cycle, and the other dimension is a three-level classification into broad application areas at different levels in healthcare. We have used this framework to carry out a quantitative analysis of all the papers presented during the meetings of ORAHS since its inception in 1975. We have furthermore made a comparison to investigate whether ORAHS papers have any distinctive characteristics which mark them out as different from the “mainstream” health OR literature.
The conclusions based on these analyses are:– Health OR is a fast growing area of research. Over time the meetings have grown from 25 to 40 participants, 10–14 countries represented and 15–25 papers presented, to large meetings with 80–150 participants, more international and global participation, and a larger number of papers.
– Comparison with the RIGHT study demonstrates that ORAHS papers do not report significantly more implementation of OR models than the general health OR literature, but that ORAHS papers, focus substantially more on the operational level, make more use of mathematical modelling and simulation, and have a tendency to be mainstream applications in the area of planning and resource utilisation.
– Using the service life cycle perspective reveals that the most popular stages for OR contributions are: developing programs and plans for using resources (24% of all papers presented), managing the performance of delivery (39%) and evaluating the performance of delivery (18%). Following the process level perspective most papers are on the level of Unit & Hospital (43%); 33% focuses on the level of region and national, and 25% on the level of patient and provider.
As challenges for health OR we have pointed at more involvement of OR researchers at the stages of identifying consumer requirements, and developing a new service, stronger collaboration with public health clinicians and epidemiologists in the stage of forecasting demand and with economists in the stage of securing resources. Other areas of challenge are developing better criteria for measuring performance (e.g. waiting times) and more realistic and robust targets for healthcare performance (e.g. occupancy levels and stochastic variation).
Healthcare organisations are in transition from a supply-orientation to a demand driven organisation. This offers many opportunities for health OR. The key challenges facing healthcare providers in future years are perhaps more organisational and logistical than medical and scientific advances. How can these complex healthcare organizations manage themselves, and deliver care efficiently and effectively to an ageing and ever more demanding population, with limited budgets, advancing medical technology and increased expectations? A Grand Challenge indeed and a key role for OR!
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