In healthcare, along with many areas of human activity, the issues of monitoring and data analysis constantly arise. Based on the data received, people make decisions and influence a particular structure of the process for which they are responsible. Then there are questions about the presentation of quantitative data. In medical practice, graphic images are used to illustrate statistical data characterizing health and healthcare indicators. Charts and graphs give businesses an easy way to visualize statistical information rather than simply presenting a series of numbers. The pie chart is one such tool for presenting a quantitative data report in a healthcare setting. Its name comes from its resemblance to a pie, as it is round in shape and shows data as slices. A pie chart that is easy to create and understand works well when simple data needs to be presented and measured, but it may not be suitable for complex needs.
A pie chart presents data in a simple and understandable way. Walters et al. (2021) affirm that it can be an effective communication tool even for an uninformed audience because it presents data visually as a fraction of a whole. Readers or audiences see data comparisons at a glance, allowing them to analyze or understand complex medical data immediately. This type of information visualization chart eliminates the need for readers to learn or measure the underlying numbers themselves, so it is an excellent way to present medical data that might otherwise appear in a table. Moreover, it is possible to manipulate parts of the data in a circular circle to emphasize the necessary points.
However, the pie chart has several disadvantages. First, a pie chart becomes less effective if it uses too many pieces of data. For example, a chart with four slices is easy to read; one with more than 10 gets smaller, mainly if it contains many slices of the same size. Etnel et al. (2020) note that with an increase in the number of fragments, the visibility effect disappears, and it will simply be impossible for the viewer to discern the percentage of elements. Adding data and number labels may not help here, as they can become crowded and hard to read independently. Thus, the maximum number of row elements was deduced by Etnel et al. (2020). This number of elements is seven, after which the visual effect of the pie chart disappears.
Second, a pie chart cannot display multiple series. This type of chart represents only one set of data, while a graph or column chart can display any number of series. Accordingly, a series of pie charts will be needed to compare multiple sets. Etnel et al. (2020) assert that this can make it difficult for readers to analyze and assimilate medical information quickly. Moreover, a pie chart cannot show the change in a function. For this, only graphs can be used.
Third, comparing slices of data in a circle also has issues because the reader must account for angles and compare nonadjacent slices. According to Etnel et al. (2020), manipulating medical data in chart design can lead readers to draw inaccurate conclusions or make decisions based on visual impact rather than data analysis. But for all its shortcomings, the pie chart has one huge advantage: it is very convenient to show the trend of the series on it. All elements of a simple series will clearly look on a pie chart. Thus, this type of chart is applicable when a single data set consisting of a small number of elements is presented. For example, pie charts can be used to represent data such as age range, cultural background, spending on various healthcare sectors, types of operations, and causes of death.
References
Etnel, J. R., de Groot, J. M., El Jabri, M., Mesch, A., Nobel, N. A., Bogers, A. J., & Takkenberg, J. J. (2020). Do risk visualizations improve the understanding of numerical risks? A randomized, investigator-blinded general population survey.International Journal of Medical Informatics, 135, 104005. Web.
Walters, S. J., Campbell, M.J., & Machin, D. (2021). Medical statistics: A textbook for the health sciences (5th ed.). John Wiley & Sons.