Methods & Tools

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Quality Assurance Tools and Methods

System Modeling

System modeling shows how the system should be working. Use this technique to examine how various components work together to produce a particular outcome. These components make up a system, which is comprised of resources processed in various ways (counseling, diagnosis, treatment) to generate direct outputs (products or services), which in turn can produce both direct effects (e.g., immunity, rehydration) on those using them and longer term, more indirect results (e.g., reduced measles prevalence or reduced mortality rates) on users and the community at large.

When to Use It

By diagramming the linkages between each system activity, system modeling makes it easier to understand the relationships among various activities and the impact of each on the others. It shows the processes as part of a larger system whose objective is to serve a specific client need. System modeling is valuable when an overall picture is needed. System modeling shows how direct and support services interact, where critical inputs come from, and how products or services are expected to meet the needs in the community. When teams do not know where to start, system modeling can help in locating problem areas or in analyzing the problem by showing the various parts of the system and the linkages among them. It can pinpoint other potential problem areas. System modeling can also reveal data collection needs: indicators of inputs, process, and outcomes (direct outputs, effects on clients, and/or impacts). Finally, system modeling can be helpful in monitoring performance.

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Elements of System Modeling

System modeling uses three elements: inputs, processes, and outcomes.

Inputs are the resources used to carry out the activities (processes). Inputs can be raw materials, or products or services produced by other parts of the system. For example, in the malaria treatment system, inputs include anti-malarial drugs and skilled health workers. Other parts of the system provide both of these inputs: the drugs by the logistics subsystem and the skilled human resources by the training subsystem.

Processes are the activities and tasks that turn the inputs into products and services. For malaria treatment, this process would include the tasks of taking a history and conducting a physical examination of patients complaining of fever, making a diagnosis, providing treatment, and counseling the patient.

Outcomes are the results of processes. Outcomes generally refer to the direct outputs generated by a process, and may sometimes refer to the more indirect effects on the clients themselves and the still more indirect impacts on the wider community.

Outputs are the direct products or services produced by the process. The outputs of the malaria treatment system are patients receiving therapy and counseling.

Effects are the changes in client knowledge, attitude, behavior, and/or physiology that result from the outputs. For the malaria treatment system, this would be reduced case fatality from malaria (patients getting better) and patients or caretakers who know what to do if the fever returns. These are indirect results of the process because other factors may intervene between the output (e.g., correct treatment with an anti-malarial) and the effect (e.g., the patient’s recovery).

Impacts are the long-term and still more indirect effects of the outputs on users and the community at large. For malaria treatment, the impacts would be improved health status in the community and reduced infant and child mortality rates.

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