Workflow support for the healthcare domain

Healthcare organizations are currently facing increasing pressure to improve productivity and to reduce costs while at the same time the demand for hospital services is growing. In these organizations, many processes are executed which are highly variable, complex, and lengthy in duration. For these processes high demands exist with regard to the in-time scheduling of tasks and the efficient coordination of multiple people involved in these tasks. When diagnosing and treating a patient a doctor typically proceeds in a step-by-step way in order to decide about the next steps to be taken. In order to provide optimal care for patients we focus on the support of organizational healthcare processes by workflow technology. Organizational healthcare processes capture the organizational knowledge which is necessary to coordinate interoperating healthcare professionals and organizational units. Based on process definitions, Workflow Management Systems (WfMSs) are able to manage the flow of work in these processes such that individual workitems are done at the right time by the proper person resulting in a more efficient and effective process execution. In order to identify limitations to current WfMSs, a large case study has been performed. In this case study a representative healthcare process of the AMC hospital in Amsterdam, the Netherlands, is implemented in multiple WfMSs. This exercise revealed two important shortcomings. First, contemporary WfMSs offer workitems to users via specific worklists. At an arbitrary point in time, resources can select workitems from this list without having a schedule in mind. However, the effective execution of workitems is often tied to the availability of multiple scarce resources. This requires that an appointment-based approach is utilized when scheduling the workitems performed by these resources. For these appointments, enough time needs to be reserved in which they can be performed in order to prevent the need for rescheduling. However, current WfMSs do not provide support for the calendar-based scheduling of workitems such that they are performed by one or more resources and at a specified time. Therefore, in this thesis, we focus on augmenting existing WfMSs with calendar-based scheduling support. Second, the process of diagnosing or treating a patient typically consists of the execution of a number of smaller workflow fragments (e.g. lab tests or a visit to a doctor) that run in conjunction with each other. Although these workflow fragments execute independently from each other, a certain ``magnetic force'' exists between them. Such a collection of workflow fragments can best be characterized as separate workflows which are weakly-connected and that interact with each other. Additionally, these workflows need to be able to deal with different levels of granularity. In other words, we are dealing with weakly-connected interacting lightweight workflows. To date, contemporary WfMSs do not offer support for weakly-connected interacting lightweight workflows which can cope with different levels of granularity. Therefore, in this thesis, we focus on augmenting existing WfMSs with inter-workflow support. The two previously mentioned issues require the extension of existing WfMSs with different functionalities. Although WfMSs are widely used in practice and are large and complex systems which provide a wide range of functions, to date, there is no accepted development approach for the configuration of WfMSs and construction of specific functionality added to these systems. Similar, there has been minimal consideration for testing the capabilities of the developed WfMS and validating its operational performance. Therefore, in this thesis, we focus on a development approach in which first a conceptual model is defined which is a complete and formal (i.e. executable) specification of the WfMS to be developed. Afterwards, the same model is used for the development, testing, and validation of the operational performance of the new WfMS. The work presented in the thesis is demonstrated by a concrete application of the proposed development approach. A detailed conceptual model has been developed describing the behavior of a WfMS augmented with both calendar-based scheduling support and inter-workflow support. This conceptual model serves as basis for the subsequent implementation of the system. Furthermore, for the WfMS extended with calendar-based scheduling support, the conceptual model has also been used for investigating the reliability of the implemented system and to investigate its operational performance by means of computer simulation.