=Paper= {{Paper |id=Vol-1812/JARCA16-paper-9 |storemode=property |title=Dynamic Management of Appointments in Sanitary Environments: A Systematic Literature Review |pdfUrl=https://ceur-ws.org/Vol-1812/JARCA16-paper-9.pdf |volume=Vol-1812 |authors=Virginia Cid-de-la-Paz,Andrés Jiménez-Ramírez,María José Escalona }} ==Dynamic Management of Appointments in Sanitary Environments: A Systematic Literature Review== https://ceur-ws.org/Vol-1812/JARCA16-paper-9.pdf
    Dynamic Management of Appointments in Sanitary Environments: a Systematic
                              Literature Review
                  Virginia Cid-de-la-Paz, Andrés Jiménez-Ramírez and María José Escalona
                   Universidad de Sevilla. Departamento de Lenguajes y Sistemas Informáticos
                             virginia.cid@iwt2.org, {ajramirez, mjescalona}@us.es



                            Abstract                                    complain about the lack of availability. To mitigate this
                                                                        discontent, we might think of reducing the time of patient
     The aim of this study is to provide an extensive                   care sessions. However, in Spain only six minutes per
     systematic literature review about the use of
                                                                        patient is allocated in average. In fact, health professionals
     dynamic programming in the management of
                                                                        are disappointed with it since they have to make quick
     appointments in health centers, providing a view                   decisions about the health of their patients. Thus, the
     of the current research environment. Dynamic
                                                                        scheduling systems of appointments are in the intersection
     programming of appointments improves the
                                                                        between efficiency and the correct access to health
     efficiency through algorithmic decision support                    services.
     tools. This technology has used successfully in
                                                                           In this paper we offer a comprehensive research study
     other industries such as airlines, car rental
                                                                        on the programming of dynamic appointments in health
     agencies and hotels. The application of this                       environments. These models have the potential to improve
     technique to the health environment has attracted
                                                                        efficiency through algorithmic decision support tools.
     the interest of many academics in the last 50
                                                                        This technology has used successfully in other industries
     years because it is very useful to improve the                     such as airlines, car rental agencies and hotels (Talluri and
     access and the quality of health systems and also
                                                                        Van Ryzin, 2004). We believe that decision support
     reduce the cost. However, the use of these
                                                                        techniques can reduce costs and improve access to health
     techniques in health settings is not trivial because               services simultaneously.
     every decision is vital for patients. In addition,
                                                                           Designing a dynamic appointment scheduling system
     we must consider other important and complex
                                                                        aims to adapt to the demand, with the availability of the
     factors such as emergencies. Therefore, we hope                    resources, and, at the same time, optimize the use of those
     to analyze the current state of this technology in
                                                                        resources and minimizes the waiting times that patients
     the health environment, identifying keys for
                                                                        suffer. In addition, it is imperative to take into account
     future research.                                                   and understand the health environment in which we are,
                                                                        outpatient, hospital, specialized centers, etc. It is
1    Introduction                                                       necessary to pay special attention to the factors that make
The objective of this work is to provide an extensive                   appointment scheduling challenging. In conclusion, to
review of the literature about the use of dynamic                       offer a roadmap in appointment management design in
programming in the management of appointments in                        health centers.
health centers. This theme has attracted the interest of                   Waiting time and congestion in waiting rooms are two
many academics over the past 50 years, from the                         of the few tangible elements of quality. Surveys indicate
pioneering works of Bailey (1952) and Lindley (1952).                   that excessive waiting time is often the main reason why
   Health care providers are under great pressure to reduce             patients are dissatisfied with the health services offered
costs and improve the quality of service. In recent years,              (Huang, 1994).
given the greater emphasis on preventive medicine, the                     Many factors affect the performance of appointments
ambulatory or the primary level of health are gradually                 systems. The delay of patients and specialists, as well as
becoming an essential component in health care.                         possible emergencies are the main factors.
   When we add factors to health care budgets such as                      Emergencies are a key factor in the design of a system
aging of the population and the increase of the chronic                 that allows us to manage efficiently the demand and the
diseases, it is not surprising that there is a growing                  resources. A good appointment system should provide
pressure on health service to improve the efficiency.                   convenient access to health services for all patients.
   Appointment systems can be a source of dissatisfaction               However, how do we prioritize emergencies? Patients'
for patients and healthcare professionals. Patients often               needs have different degrees of urgency, and the decision-


Copyright @ by the paper’s authors. Copying permitted for private and
academic purposes.
In: Zoe Falomir, Juan A. Ortega (eds.): Proceedings of JARCA 2016,
Almería, Spain, June 2016, published at http://ceur-ws.org
making process we are proposing must be automatic. That         number of patients that can be placed in a time zone, the
is, decisions must be made before having complete               prioritization of patients, and the function to be optimized.
information about urgency.                                      In addition, we find other characteristics to consider in the
   In conclusion, we wish to deepen in this theme and           process of patients’ arrivals, like the possible
present the general considerations to be taken into account     unpunctuality or absence of patients and/or professionals,
in the modeling of problems. Therefore, we provide a            as well as urgencies.
taxonomy of the methodologies used in the existing                 On the other hand, (D Gupta and Denton, 2008) present
literature and we can help to understand how to model a         a constructive criticism of the studies which are done until
dynamic appointment system.                                     the date. As a consequence, this article proposes other
                                                                aspects, besides those mentioned in (Cayirli and Veral,
2   Review Process                                              2009). Such aspects have to be taken into account as main
                                                                attributes when we want to develop a dynamic
This study has been undertaken as a systematic literature       appointment management system: service time (e.g.,
review (SLR) based on the original guidelines as proposed       difficult to assign a fixed time to a Surgery), doctor's and
by Kitchenham (B.A. Kitchenham et al., 2004) to achieve         patient's preferences (e.g., a patient usually wants to see
the goal described in Section 1: provide an extensive           your doctor, schedules) and indirect waiting time (e.g.,
review of the literature about the use of dynamic               time from appointment until appointment day). Also, this
programming in the management of appointments in                work studies the complexity of these properties in a
health centers. A systematic literature review allow            sanitary environment (outpatient, outpatient appointment
identifying, evaluating and interpreting all available          and surgery). This aspect is very interesting and adverts us
research data relevant to a particular research question in a   how we must design a tool to support decision making in
specific investigation area. The guides proposed, which         appointment management exclusively for physicians and
are among the most widely accepted in software                  the environment, without considering patients.
engineering, have been followed to carry out this work.            From these reviews, we pretend to make a study to see
   These guidelines establish that a review should              the advances made in the technique to the present date.
comprise three phases: planning, conducting and                 For that, we focus on all the studies that consider the
reporting. The planning activity deals with developing the      patient as the main user to take into account. Also, it is
review protocol as well as deciding how the researchers         important not only to take into account the patient waiting
should work and interact to conduct the review. This            time on the day of their appointment, but also to
protocol prescribes a controlled procedure for executing        contemplate the time that passes from an appointment
the review and includes research questions, search and          until the date of the appointment, because, surely, it is
evaluation strategies, inclusion/exclusion criteria, quality    related to the probabilities of cancellation and delay.
assessment, data collection form and methods of analysis.          Based on these, some questions are asked to be
The second phase focuses on executing the protocol as it        completed in this new systematic review of the literature.
has been defined. Finally, the last phase describes how the        RQ1. Are there currently applications that use dynamic
final report has been elaborated.                               programming to help manage patients in the healthcare
                                                                environment?
2.1 Research Questions                                             RQ2. Are the patient's preferences taken into account
To begin the present study, we search similar systematic        when making an appointment?
reviews following the planned searches that its described          RQ3. What health environments have adopted dynamic
in the present and the following subsection. The results        programming for managing appointments? Differences to
obtained are described below.                                   keep in mind?
   Two literature reviews were found. Both are from more           RQ4. How to mitigate the effects of cancellations and
than five years ago, but they are very useful to start in the   non-presentations of patients?
world of dynamic appointment management, as well as                RQ5. Is the time between the request of the
recognizing the main properties to take into account. Due       appointment and the day of the appointment (indirect
to its high interest and although one of them is of the year    time) taken into account?
2003 and fails one of the quality requirements mentioned           RQ6. How to manage emergencies and their priorities?
in section 2.3, it has been considered.
   On the one hand, in the oldest review of the selected        2.2 Search Strategy
ones, made by (Cayirli and Veral, 2009), we can find an         This section details how the search for related articles has
analysis of the main characteristics to take into account       been done. The keywords used and the chosen
when you want to design a system to manage                      bibliographic engines are presented.
appointments in a health environment as faithful as                At first, some keywords were defined which were
possible. Among other properties, we focus on those             increasing as related articles were found since we learned
properties that make appointment’s programming a                from the keywords of those articles found.
challenge. Among them, it is necessary to highlight the
  After several tests, the keywords are concluded in                                         article has been in circulation for several years and its number
Table 1.                                                                                     of citations has not increased in relation, we can consider it as a
                                                                                             signal of the quality of that article.

A1. Health      B1.Dynamic     C1.Appointment     D1. Programming   E1. Review
                                                                                   Table 3. Inclusion and exclusion criteria
                                                  D2. Scheduling    E2. Software

Table 1 Keywords
                                                                                     However, it should be mentioned that in the second
                                                                                   phase (i.e., publications since 2006), some articles have
In addition, Table 2 presents the search expressions                               not been taken into account for the article. Although it
representing the different combinations of keywords done                           does not achieve the requirement, it is very useful to
for the search.                                                                    immerse ourselves in the world of dynamic programming
                                                                                   in healthcare environments, giving an overview of
“A1 AND B1 AND D2”                          Health dynamic scheduling              everything that has to be taken into account. Therefore, it
                                                                                   was decided not to exclude them.
“A1 AND B1 AND D2 AND E1”                   Health dynamic scheduling review
                                                                                   2.4 Quality criteria
“A1 AND B1 AND C1 AND D2”                   Health dynamic appointment             In this section, we determine the quality criteria. Once the
                                            scheduling
                                                                                   articles have exceeded the criteria of admission and
                                                                                   exclusion, the article’ properties are evaluated to know
“A1 AND B1 AND C1”                          Health dynamic appointment
                                                                                   their quality. Each quality judgment can take the values
“B1 AND C1 AND E2 AND A1”                   Dynamic scheduling software            yes or no and, in some cases, including the value
                                            health                                 “partially”. All the quality criteria considered and their
                                                                                   possible values are explained in Table 4.
Table 2 Search terms
In order to perform the search, we considered the Google                           QA                                Values

Scholar, Fama (catalog of magazines and books of the                                                                 O Yes: it is possible to read and understand
                                                                                   QA1. Is the text readable?        without being an expert on the subject.
University of Seville), IEEE, Scopus and PubMed data                                                                 O Partially: In certain aspects, it is necessary
sources. In them, the search expressions (cf. Table 2) were                                                          prior experience.
introduced for obtaining new revisions and studies that                                                              O No: difficult to understand.
conclude some of the challenges raised in section 2.1.                             QA2. Limitations have been        O Yes: define the limits of the study done.
   The articles collected from the different databases were                        described?                        O No: does not describe the boundary of the
                                                                                                                     study developed.
managed through the Mendeley tool.
                                                                                   QA3.There are future lines of     O Yes: present a series of ideas to continue the
2.3 Inclusion and exclusion criteria                                               research?                         research.
                                                                                                                     O No: there are not claims on possible
Thereafter, we define the admission and exclusion criteria.                                                          innovations.
With those criteria, we justify whether to consider or not
                                                                                                                     O Yes: presents the results obtained in the
the articles which are found on the aforementioned search                          QA4. Have the results been        study.
                                                                                   presented?
engines. Thus, we can identify the most relevant articles                                                            O Partially: reference to other articles.
                                                                                                                     O No: does not clarify the results of the
to develop our review of the literature.                                                                             investigation.
   The inclusion/exclusion criteria are carried out in five
                                                                                   QA5. Has the algorithm been       O Yes: health domain analysis.
phases presented in Table 3.                                                       tested?                           O No: the characteristics of the health area are
                                                                                                                     not detailed.

Phase        Inclusion/exclusion criteria                                                                            O Yes: health domain analysis.
                                                                                   QA6. Has the health application
                                                                                                                     O No: the characteristics of the health area are
                                                                                   environment been described?
                                                                                                                     not detailed.
P1           Article related to dynamic scheduling of appointments in the
             health field. Inclusion of keywords.                                  QA7. Has the cost function to     O Yes: description of the function to be
                                                                                   optimize been defined?            maximized or minimized.
             Publications since 2006                                                                                 O No: the optimization function is not
P2
                                                                                                                     detailed.

P3           Availability of the full text for free.                               Tabla 4. Quality criteria

P4           Not duplicated
                                                                                   2.5 Characterization Scheme
P5           Number of citations relevant, always keeping in mind its year         In order to evaluate and classify the selected articles, a
             of publication. If an article has been released in a date close to    scheme dedicated to organizing and cataloging the
             the present, it is logical to find few citations. However, if an
information found in the articles is made. Thus, it is easy      In Table 5 we illustrate the schema definition, and in
to have an overview of each article. Based on this scheme,     section 3.2 we instantiate it with the selected articles.
we describe the results obtained responding to the
research questions described in section 2.1.


Characterization Scheme
Element          Characteristic                        Value
General          Author                                {}
Information
                 Year                                  {}

                    Title                              {}

                    Number of citations                {}

                    Journal                            {}

                    Source                             {}

                    Theoretical/experimental           {Theoretical with reviews to experimental studies,
                                                       theoretical studies, experimental studies}
Modelling           Area of application                {External consultations, treatment, surgery,
                                                       outpatients clinics, nursing, combination of the
                                                       above}
                    Delays                             {Theoretical, Experimental, No}

                    Cancellations                      {Theoretical, Experimental, No}

                    Patient’s preferences              {Theoretical, Experimental, No}

                    Emergencies                        {Theoretical, Experimental, No}

                    Prioritization of emergencies      {Theoretical, Experimental, No}

                    Attention to the time passed       {Theoretical, Experimental, No}
                    between the request of the
                    appointment and the day of the
                    appointment

                    Cost function to optimize          {Patient waiting time, physician downtime, cost
                                                       reduction, time from appointment request to
                                                       appointment day, combination of the above}

Results             Results presented                  {Yes (mentioning other studies), Yes, No}

                    Test results                       {simulation, case study, both, Statistical, No (is a
                                                       literature review)}
Table 5. Characterization Scheme
  With the General Information element we pretend to
collect the main characteristics of the selected articles,
including the Author, Year, Title of the article, the Journal
and the Source where it was written.
   In the Modelling, it is tried to visualize in which
articles we can find answers to the research questions
RQ2, RQ3, RQ4, RQ5 and RQ6, as well as for QA6 and
QA7 quality criteria.
   Finally, we expose the form of resolution and the
response of the QA4 and QA5 quality criteria in the
Result element.
                                                                Figure 1. Inclusion criteria
3   Results
This section presents the results obtained after doing the
planning described in section 2. First, we explain the
results obtained in the various searches performed. After
that, we evaluate these articles according to the quality
criteria defined in section 2.4.

3.1 Search results
The search process was developed with the keywords
described in section 2.2 and introducing them into the          Figura 2. Exclusion criteria
bibliographic engines specified in section 2.2. Once the
                                                                The inclusion/exclusion phase that restricts most the
results were obtained, it was checked which the inclusion
                                                                search is the first. With the first criteria, we are sure that
and exclusion criteria. After this, the number of articles
                                                                we select articles related to the management of dynamic
was considerably reduced, finding difficulties to select a
                                                                appointments in health environment, and the keywords are
number of notable articles to perform a good systematic
                                                                chosen are in the article.
review.
                                                                   Subsequently, phase 2 (i.e., articles published in the last
   The first search was made in Google Scholar, not
                                                                ten years) also excludes a considerable number of studies.
finding any new articles in the other databases, besides
                                                                This criterion helps us to make a review of the most
those already provided by Google Scholar. In addition,
                                                                current literature.
FAMA is discarded since it was not possible to collect
any article related to the subject.                             3.2 Analysis of selected articles
   In Figure 1 and Figure 2 we can graphically display the
number of articles included and excluded by inclusion and       Finally, we highlight eight articles by instantiating the
exclusion criteria respectively.                                schema definition designed in section 2.5 (Table 6 – Table
                                                                13).
Schema of Appointment scheduling in health care: Challenges and opportunities article
Element         Characteristic                   Value
General         Author                           Diwakar Gupta and Brian Denton
Information
                Year                             2008

                    Title                                  Appointment scheduling in health care: Challenges
                                                           and opportunities

                    Number of citations                    385

                    Journal                                IIE Transactions

                    Source                                 Graduate Program in Industrial & Systems
                                                           Engineering, Department of Mechanical Engineering,
                                                           University of Minnesota

                    Theoretical / Experimental             Theoretical with reviews of experimental studies

Modelling           Area of application                    Combination (External consultation, Outpatient clinic
                                                           and Surgery)

                    Delays                                 Theoretical

                    Cancellations                          Theoretical

                    Patients’ preferences                  Theoretical

                    Emergencies                            Theoretical

                    Priority of emergencies                Theoretical

                    Attention to the time passed           Theoretical
                    between the request of the
                    appointment and the day of the
                    appointment


                    Cost function to optimize              Combination of waiting time suffered by the patients
                                                           and time of inactivity of the doctor)

Results             Results presented                      Yes (mentioning other studies)

                    Test results                           No (it is a literature review)
Table 6. Schema of Appointment scheduling in health care: Challenges and opportunities article
Schema of Outpatient Scheduling in Health Care: a Review of Literature article
Element         Characteristic                   Value
General         Author                           Tugba Cayirli and Emre Veral
Information
                Year                             2003

                     Title                                 Outpatient Scheduling in Health Care: a Review of
                                                           Literature

                     Number of citations                   535

                     Journal                               Production and Operations Management Society

                     Source                                Hofstra University, Department of Management,
                                                           New York

                     Theoretical / Experimental            Theoretical with reviews of experimental studies

Modelling            Area of application                   External consultation

                     Delays                                Experimental

                     Cancellations                         No

                     Patient’s preferences                 No

                     Emergencies                           Experimental

                     Priority of emergencies               No

                     Attention to the time passed          No
                     between the request of the
                     appointment and the day of the
                     appointment

                     Cost function to optimize             Combination of waiting time suffered by the patients
                                                           and time of inactivity of the doctor)

Results              Results presented                     Yes (mentioning other studies)

                     Test results                          No (it is a literature review)


Table 7. Schema of Outpatient Scheduling in Health Care: a Review of Literature article
Schema of Dynamic Scheduling of Outpatient Appointments Under Patient No-Shows and
Cancellations article
Element            Characteristic              Value
General            Author                      Nan Liu, Serhan Ziya and Vidyadhar G. Kulkarni
Information
                   Year                        2010

                    Title                                Dynamic Scheduling of Outpatient Appointments
                                                         Under Patient No-Shows and Cancellations.

                                                         139
                    Number of citations
                                                         -
                    Journal

                    Source                               Department of Statistics and Operations Research,
                                                         University of North Carolina

                    Theoretical / Experimental           Experimental

Modelling           Area of application                  External consultations

                    Delays                               Experimental

                    Cancellations                        Experimental

                    Patient’s preferences                Experimental

                    Emergencies                          No

                    Priority of emergencies              No

                    Attention to the time passed         Experimental
                    between the request of the
                    appointment and the day of the
                    appointment

                    Cost function to optimize            Cost reduction

Results             Results presented                    Yes

                    Test results                         simulation
Table 8. Schema of Dynamic Scheduling of Outpatient Appointments Under Patient No-Shows and Cancellations article
Schema of Designing appointment scheduling systems for ambulatory care services article
Element          Characteristic                 Value
General          Author                         Tugba Cayirli, Emre Veral and Harry Rosen
Information
                 Year                           2006

                    Title                                 Designing appointment scheduling systems for
                                                          ambulatory care services.

                    Number of citations                   209

                    Journal                               -

                    Source                                Hofstra University, Department of Management

                    Theoretical / Experimental            Experimental

Modelling           Area of application                   Outpatients clinics

                    Delays                                Experimental

                    Cancellations                         No

                    Patient’s preferences                  No

                    Emergencies                           Experimental

                    Priority of emergencies                No

                    Attention to the time passed          No
                    between the request of the
                    appointment and the day of the
                    appointment

                    Cost function to optimize             Combination of waiting time suffered by the patients
                                                          and time of inactivity of the doctor)

Results             Results presented                     Yes

                    Test results                          simulation
Table 9. Schema of Designing appointment scheduling systems for ambulatory care services article
Schema of Dynamic multi-appointment patient scheduling for radiation therapy article
Element        Characteristic                  Value
General        Author                          Walter J. Gutjahr, Marion S. Raunerb
Information
               Year                            2012

                    Title                                 An ACO algorithm for a dynamic regional nurse-
                                                          scheduling problem in Austria

                    Number of citations                   41

                    Journal                               Elsevier

                    Source                                Sauder School of Business, University of British
                                                          Columbia
                    Theoretical / Experimental            Experimental

Modelling           Area of application                   Treatment

                    Delays                                Experimental

                    Cancellations                          No

                    Patient’s preferences                 Theoretical

                    Emergencies                           Experimental

                    Priority of emergencies               No

                    Attention to the time passed          No
                    between the request of the
                    appointment and the day of the
                    appointment

                    Cost function to optimize             Waiting time patients

Results             Results presented                     Yes

                    Test results                          simulation
Table 10. Schema of Dynamic multi-appointment patient scheduling for radiation therapy article
Schema of Dynamic scheduling with due dates and time windows: an application to chemotherapy
patient appointment booking article
Element          Characteristic                 Value
General          Author                         Yasin Gocgun and Martin L. Puterman
Information
                 Year                           2014

                    Title                                Dynamic scheduling with due dates and time
                                                         windows: an application to chemotherapy patient
                                                         appointment booking
                    Number of citations
                                                         10
                    Journal
                                                         Health Care Management Science

                    Source                               Centre for Maintenance Optimization Reliability
                                                         Engineering, Department of Mechanical Industrial
                                                         Engineering, University of Toronto and Operations
                                                         and Logistics Division, Sauder School of Business,
                                                         University of British Columbia,

                    Theoretical / Experimental           Experimental

Modelling           Area of application                  Treatment

                    Delays                               Experimental

                    Cancellations                        Experimental

                    Patient’s preferences                No

                    Emergencies                          Experimental

                    Priority of emergencies              Experimental

                    Attention to the time passed          No
                    between the request of the
                    appointment and the day of the
                    appointment

                    Cost function to optimize            Cost reduction

Results             Results presented                     Yes

                    Test results                         simulation
Table 11. Schema of Dynamic scheduling with due dates and time windows: an application to chemotherapy patient appointment
booking article
Schema of Clinic Overbooking to Improve Patient Access and Increase Provider Productivity article
Element          Characteristic                  Value
General          Author                          Linda R. LaGanga and Stephen R. Lawrence
Information
                 Year                            2007

                    Title                                 Clinic Overbooking to Improve Patient Access and
                                                          Increase Provider Productivity

                    Number of citations                   180

                    Journal                               Decision Sciences Institute

                    Source                                Mental Health Center of Denver and University of
                                                          Colorado at Boulder

                    Theoretical / Experimental            Experimental

Modelling           Area of application                   Outpatients clinics

                    Delays                                 Experimental

                    Cancellations                         Experimental

                    Patient’s preferences                 No

                    Emergencies                           Experimental

                    Priority of emergencies               No

                    Attention to the time passed          No
                    between the request of the
                    appointment and the day of the
                    appointment

                    Cost function to optimize             Cost reduction

Results             Results presented                      Yes

                    Test results                          simulation
Table 12. Schema of Clinic Overbooking to Improve Patient Access and Increase Provider Productivity article
Schema of Revenue management for a primary care clinic in the presence of patient choice article
Element         Characteristic                Values
General         Author                        Diwakar Gupta and Lei Wang
Information
                Year                          2008

                     Title                                 Revenue management for a primary care clinic in the
                                                           presence of patient choice.

                     Number of citations                   119

                     Journal                               Operations Research

                     Source                                Department of Mechanical Engineering, University
                                                           of Minnesota, Minneapolis, Minnesota and SmartOps
                                                           Corporation, Pittsburgh, Pennsylvania

                     Theoretical / Experimental            Experimental

Modelling            Area of application                   Outpatients clinics

                     Delays                                No

                     Cancellations                         No

                     Patient’s preferences                 No

                     Emergencies                           Experimental

                     Priority of emergencies               Experimental

                     Attention to the time passed          No
                     between the request of the
                     appointment and the day of the
                     appointment

                     Cost function to optimize             Cost reductions

Results              Results presented                     Yes

                     Test results                          Statistical
Table 13. Schema of Revenue management for a primary care clinic in the presence of patient choice article
   We study the distribution of these articles over time           close to the current year. On the contrary, it is easier to
thanks to Figure 3.                                                find articles related to the subject before 2010. However,
                                                                   we wanted to maintain the initial idea, in order to try to
                                                                   write a literature review as current as possible.
                                                                      With relation to the source of each article, note that all
                                                                   articles have been found in all of the chosen bibliographic
                                                                   sources. That is, no article was discovered exclusively in
                                                                   any of the sources.

                                                                   3.3 Quality of selected articles
                                                                   Having commented the selected articles, we proceed to
Figure 3. Distribution in time of articles                         evaluate the quality of these according to the norms
   Although we initially wanted to obtain articles from the        defined in section 2.4. This evaluation is shown in Table
last 10 years, we can conclude that this claim was too             14.
ambitious. We have got only eight articles and few are

                                     QA1            QA2       QA3         QA4                 QA5                 QA6     QA7
Appointment scheduling in            Yes            Yes       Yes         Partially           Partially           Yes     Yes
health care Challenges and
opportunities

Outpatient Scheduling in Health      Yes            Yes       Yes         Partially           Partially           Yes     Yes
Care: a Review of Literature


Dynamic Scheduling of                Partially      Yes       Yes         Yes                 Yes                 Yes     Yes
Outpatient Appointments
Under Patient No-Shows and
Cancellations

Designing appointment                Partially      Yes       Yes         Yes                 Yes                 Yes     Yes
scheduling systems for
ambulatory care services

Dynamic multi-appointment            Partially      Yes       No          Yes                 Yes                 Yes     Yes
patient scheduling for radiation
therapy


Dynamic scheduling with due          Partially      Yes       No          Yes                 Yes                 Yes     Yes
dates and time windows: an
application to chemotherapy
patient appointment booking


Clinic Overbooking to Improve        Partially      Yes       Yes         Yes                 Yes                 Yes     Yes
Patient Access and Increase
Provider Productivity


Revenue management for a             Partially      Yes       No          Yes                 Yes                 No      Yes
primary care clinic in the
presence of patient choice.
Table 14. Quality os articles
In Figure 4 we visualize the percentage of quality,                of the patient, two theoretically and one experimentally.
differentiating the possible values that can take, indicated in    This may be due, as mentioned (Liu, Ziya, and Kulkarni
section 2.4.                                                       2010), to the difficulty to design models that take into
                                                                   account the needs of patients, obtaining complex
                                                                   mathematical models. In addition, in his experimental study,
                                                                   he concludes that such models have an arduous
                                                                   computation, despite being able to make a model in which
                                                                   the patient is presented with a set of possibilities in which to
                                                                   put only his appointment. That is, from my point of view,
                                                                   the preferences of the patient are not being considered in the
                                                                   model, e.g., to contemplate their working hours. In these
                                                                   studies, the system gives to the patient a set of optional days
                                                                   to choose which one is preferred.
                                                                      Therefore, we should continue to investigate and research
Figure 4. Quality evaluation
                                                                   on how to keep patient preferences in the model.
                                                                      Finally, it should be emphasized that none of the three
   The QA2 and QA7 quality criteria are perfectly satisfied        articles say that contemplating these priorities can produce
with 100% of acceptance. On the one hand, we found,                penalties in the function to be optimized. It's just a design
thanks to QA1, that reading about 60% of the articles is a bit     challenge.
difficult if one is not an expert in these topics. On the other
                                                                      RQ3. What health environments have been
hand, almost 40% of the articles do not present any review
                                                                   implemented dynamic programming in managing of
to future investigations, fact remarkable. Related to the          appointments? Differences to keep in mind?
results and the test of algorithms (i.e., QA4 and QA5), we            Practically all studies have been done in all possible
were satisfied with the conclusion of the evaluation, since        health areas: outpatient clinics, external consultations,
all of the selected articles present results or they are tested.   nursing, treatment and surgery. We have not found articles
   Finally, in terms of QA6, we find that only an article does     that have tried to simulate the operation of a hospital. It is
not describe the sanitary environment of application.              logical because is easier to start reproducing smaller
                                                                   environments.
4   Discusion                                                         In Figure 5 we show the distribution of articles by area of
                                                                   application.
In this section, we answer the research question defined in
section 2.1 considering the knowledge assimilated from the
set of articles. Note that the main objective is to know the
current state of dynamic programming in the management in
health centers, focusing on certain challenges launched by
(D Gupta and Denton, 2008). Therefore, the analysis will
divide this section into parts, each one corresponding to one
of the research questions.
   RQ1. Are there currently applications that use
dynamic programming to help manage patients in the
healthcare environment?
   Despite intense research on software that supports
dynamic appointment management in health environments,
no article has been got in which the implantation of this
technique in a real sanitary environment is reflected.
                                                                   Figure 5. Distribution by area of application
   RQ2. Are the patient's preferences taken into account
when making an appointment?                                           It is not surprising that the sum of each block shown in
   A fundamental idea, launched by (D Gupta and Denton             Figure 6 illustrates more than eight articles because several
2008). It is a factor that should not be neglected because it      articles dealt with more than one application domain.
directly affects the probability of cancelling an appointment      Studying this graphic we discerned that we find more
or being delayed. This relationship is completely logical. If      articles related to the Ambulatory environment, followed
the patient's preferences are not taken into account, the          closely by the External Consultations since both domains
patient can lose the interest in the appointment, favouring        are similar.
delays or forgetfulness.                                              On the contrary, Surgery and Treatment are environments
   However, few articles discuss this subject. Only three          more hostile. More characteristics that are vital must be
articles of the eight contemplated, mention the preferences        taken into account in the other domains. For example, for
treatments, we include the articles (Gocgun and Puterman,          paradoxically the time increases. Therefore, the
2014; Saur et al., 2012), which are intended to manage             experimental studies presented are conclusive.
appointments for the treatment of chemotherapy and                    RQ5. Is the time between the request of the
radiotherapy respectively. In this scenario, times are             appointment and the day of the appointment (indirect
essential to ensure the best saving percentage. Without            time) taken into account?
forgetting the urgencies. Moreover, cancellations and delays          In the one hand, only (Liu, Ziya, and Kulkarni 2010)
have a great impact on time and, significantly, on costs           performs experimental tests trying to minimize the time
because they are expensive treatments.                             between the day that the patient asked for an appointment,
   About surgery, thanks to one of our basic articles (D           and the date of the appointment. This topic is already
Gupta and Denton, 2008), we know the difficulty to model           mentioned in the previous section because of its intimate
an appointment management system for that environment.             relationship with cancellations. However, as discussed
The main impediment is the impossibility of generalizing           above, nothing clear can be discerned from this study.
the operating times. Not all bodies are the same, is possible         On the other hand, (D Gupta and Denton 2008) claims to
to appear complications in the surgery, and not all surgeons       investigate the reason for such cancellations or absences.
operate at the same speed. Of course, without forgetting the          RQ6. How to manage emergencies and their
emergencies. The emergencies are vital so we should                priorities?
minimize the waiting time of them, without neglecting or              It is an essential aspect in the sanitary domains and it is
disfavouring the rest of the patients.                             difficult to model. In Figure 7 we show a comparison of
   Therefore, although all are domains of the health world         both properties, urgencies and its prioritization, looking to
and the properties to contemplate are similar, when                observe how many of the selected articles perform
designing them it is essential to obtain close appointments,       experimental tests contemplating emergencies and also
not very far in time, and it is indispensable to quickly           prioritization.
manage urgencies.
   RQ4. How to mitigate the effects of cancellations and
non-presentations of patients?
   About the possible cancellation or non-presentation of the
patient, we show in Figure 6 the attribute of the schema
definition designed in Section 2.5, with the values obtained
for the set of articles formed.




                                                                   Figure 7. Emergencies – Priorities
                                                                      Although five of the articles selected, out of a total of
                                                                   eight, perform experimental tests attending urgencies, only
                                                                   two of them consider their prioritization.
Figure 6. Articles that complain in the Cancellations of patient
                                                                      However, such studies warn of the complexity of
   Note that half of the selected articles (four) do not           modelling a dynamic appointment management system that
contemplate the possible cancellations, a very common fact         accepts urgency. (Caylani, Veral, and Rosen 2006, Gurgun
and for which the dynamic scheduling of appointments               and Puterman 2014, Diwakar Gupta and Lei 2008, Laganga
would be a great help. If a patient cancels his appointment,       and Lawrence 2007, Saur et al., 2012) save certain time
and we have a dynamic appointment manager, that gap will           zones to be used for emergencies. However, if these are not
be reused efficiently.                                             used, it is a waste of time, with its consequent influence on
   The experimental study (Liu, Ziya, and Kulkarni 2010)           costs. In addition, such time reservation increases the time
reinforces the idea of the close relationship between the time     lag between the day that the patient asked for an
from the request of the appointment to the date of the             appointment and the day of the provided appointment which
appointment, and the probability of cancellation or absence.       is an undesirable fact. Therefore, it is necessary to keep on
However, the three articles that account for cancellations         researching.
(Gocgun and Puterman 2014, Laganga and Lawrence 2007,
Liu, Ziya, and Kulkarni 2010) coincide in the following: if
we try to minimize the probability of cancellation,
5   Conclusions and future work                                    all, they are recovering time gaps for possible emergencies,
                                                                   and if they are not used, we will lose that time.
After performing the analysis, we highlight the key points to         Despite the problems still present, decision-making
take into account to model an appointment management               techniques are fully applicable in health domains. Although
system for a health environment.                                   the results indicate that the current state of technology is on
   The main point is to know the characteristics of the            the right way, there is still a long way to obtain reliable
sanitary environment that we wish to model. In this                software.
systematic review of the literature, we have found modeling           In fact, nowadays many clinics continue to manage their
about outpatient centers, outpatient consultations, treatments     appointments under the supervision of a person, without any
and surgery. Among them, they present great differences            support at all. So, it is necessary to emphasize that this
that have to be considered for a correct modeling of their         technology is not being developed to supplant people, only
appointment’s manager. In short, the challenges of the             to help them. As stated, this is a domain in which the
health center, as well as its objective, must be clear.            mistakes are paid expensive, so it would be helpful to have a
   For example, the goal of an outpatient may be to plan the       software that calculates the most optimal appointment for
maximum possible number appointments in the day (always            the patient who requests it, without losing the person in
on a minimum quality of care). A cancellation per day in           charge of full control of the schedule. That is, health
this environment may not have much influence on costs.             professionals should not view this technique as a threat
   However, if we move to the management of                        because is only a support for them. So, we must continue
chemotherapy appointments, the indirect waiting time of the        working on improving this technique, as well as giving
patient (time it takes from the date that a patient requests for   visibility to its advantages in the health world.
an appointment until the date of the appointment) begins to
become vitally important, since the percentage of salvation
depends on it. In addition, cancellations in such expensive
                                                                   References
treatments are costly.                                             [Bailey, N, 1952], “A Study of Queues and Appointment
   As already noted (D Gupta and Denton 2008), the indirect        Systems in Hospital Outpatient Departments with Special
waiting time and the probability of cancellation or non-           Reference to Waiting Times,” Journal of the Royal
presentation of the patient are closely related. However,          Statistical Society 14, 185–199.
after this study, we have not found any methodology to
follow to solve this problem. For example, if we try to            [Cayirli, Tugba, and Emre Veral., 2009] “Outpatient
decrease the probability of cancellations, paradoxically the       Scheduling in Health Care: A Review of Literature.”
indirect waiting time increases according to (Gocgun and           Production and Operations Management 12(4): 519–49.
Puterman 2014, Laganga and Lawrence 2007, Liu, Ziya,
and Kulkarni 2010).                                                [Cayirli, Tugba, Emre Veral, and Harry Rosen.,
   As future work, it could be interesting to carry out an         2006]“Designing Appointment Scheduling Systems for
analysis of the cancellations and non-presentations main           Ambulatory Care Services.” Health Care Management
causes, in order to better address the problem.                    Science 9(1): 47–58.
   About patient preferences as a method to reduce the
probability of cancellation or non-presentation of the             [Gocgun, Yasin, and Martin L. Puterman, 2014] “Dynamic
patient, its modeling and its execution are complex.               Scheduling with Due Dates and Time Windows: An
However, we believe that it should continue to be a line of        Application to Chemotherapy Patient Appointment
future research. One line of research could be the                 Booking.” Health Care Management Science 17(1): 60–76.
restructuring of the management of appointments depending
on the social actor who requests it. For example, preventing       [Gupta, D, and B Denton, 2008] “Appointment Scheduling
that retired people collapse the earliest appointments in the      in Health Care: Challenges and Opportunities.” IIE
morning, when they may be the most accessible for workers.         Transactions 40(9): 800–819.
A study of such strategies would be desirable to see if they
would improve the probability of cancellations and                 [Gupta, Diwakar, and Wang Lei, 2008] “Revenue
forgetting.                                                        Management for a Primary-Care Clinic in the Presence of
   In short, we must continue to investigate new ways to           Patient Choice.” Operations Research 56(3): 576–92.
avoid cancellations and non-presentations by patients,             http://search.ebscohost.com/login.aspx?direct=true&db=bth
always keeping in mind their close relationship with the           &AN=33204706&site=ehost-live.
indirect waiting time.
   Other key pillars in modeling any appointment manager           [Huang, X, 1994] “Patient Attitude Towards Waiting in an
for a health care environment are urgencies and their              Outpatient Clinic and Its Applications,” Health Services
prioritization. In this regard, we must continue to investigate    Management Research,7,2–8.
since the solution proposed by Caylani, Veral, and Rosen
2006, Gurgun and Puterman 2014, Diwakar Gupta and Law              [Laganga, Linda R., and Stephen R. Lawrence.,
2008, Laganga and Lawrence 2007, Saur et al. Al., 2012)            2007.]“Clinic Overbooking to Improve Patient Access and
not used the full potential of dynamic programming. After
Increase Provider Productivity.” Decision Sciences 38(2):
251–76.

[LINDLEY, D. V,.(1952] “The Theory of Queues with a
Single Server,” Proceedings Cambridge Philosophy Society,
48, 277–289.

[Liu, N., S. Ziya, and V. G. Kulkarni, 2010] “Dynamic
Scheduling of Outpatient Appointments Under Patient No-
Shows and Cancellations.” Manufacturing & Service
Operations Management 12(2): 347–64.

[Sauré, Antoine, Jonathan Patrick, Scott Tyldesley, and
Martin L. Puterman., 2012] “Dynamic Multi-Appointment
Patient Scheduling for Radiation Therapy.” European
Journal of Operational Research 223(2): 573–84.