SaTScan is a software tool that employs

scan statistics In statistics, a scan statistic or window statistic is a problem relating to the clustering of randomly positioned points. An example of a typical problem is the maximum size of a cluster of points on a line or the longest series of successes record ...

for the spatial and temporal analysis of clusters of events. The software is trademarked by

Martin Kulldorff Martin Kulldorff (born 1962) is a Swedish biostatistician. He was a professor of medicine at Harvard Medical School from 2003 until his dismissal in 2024. He is a member of the US Food and Drug Administration's Drug Safety and Risk Management ...

, and was designed originally for public health and epidemiology to identify clusters of cases in both space (geographical location) and time and to perform statistical analysis to determine if these clusters are significantly different from what would be expected by chance The software provides a user-friendly interface and a range of statistical methods, making it accessible to researchers and practitioners. While not a full

Geographic Information System A geographic information system (GIS) consists of integrated computer hardware and Geographic information system software, software that store, manage, Spatial analysis, analyze, edit, output, and Cartographic design, visualize Geographic data ...

, the outputs from SaTScan can be integrated with software such as

ArcGIS ArcGIS is a family of client, server and online geographic information system (GIS) software developed and maintained by Esri. ArcGIS was first released in 1982 as ARC/INFO, a command line-based GIS. ARC/INFO was later merged into ArcGIS De ...

QGIS QGIS is a geographic information system (GIS) software that is free and open-source. QGIS supports Windows, macOS, and Linux. It supports viewing, editing, printing, and analysis of geospatial data in a range of data formats. Its name comes from ...

to visualize and analyze spatial data, and to map the distribution of various phenomena.

Analysis

SaTScan employs scan statistics to identify

clusters may refer to: Science and technology Astronomy * Cluster (spacecraft), constellation of four European Space Agency spacecraft * Cluster II (spacecraft), a European Space Agency mission to study the magnetosphere * Asteroid cluster, a small ...

of space and time phenomena. Scan statistics use regular shapes (usually circles) of varying sizes to evaluate a study area. Within each circle, the software computes if the phenomena within the circle is significantly different than expected compared to the area outside the circle. SaTScan can analyze data retrospectively or prospectively. It can look at the data spatially, temporally, or simultaneously incorporate both space and time. SaTScan can incorporate numerous probability models, including

Poisson distribution In probability theory and statistics, the Poisson distribution () is a discrete probability distribution that expresses the probability of a given number of events occurring in a fixed interval of time if these events occur with a known const ...

Bernoulli distribution In probability theory and statistics, the Bernoulli distribution, named after Swiss mathematician Jacob Bernoulli, is the discrete probability distribution of a random variable which takes the value 1 with probability p and the value 0 with pro ...

Monte Carlo method Monte Carlo methods, or Monte Carlo experiments, are a broad class of computational algorithms that rely on repeated random sampling to obtain numerical results. The underlying concept is to use randomness to solve problems that might be ...

, and

multinomial distribution In probability theory, the multinomial distribution is a generalization of the binomial distribution. For example, it models the probability of counts for each side of a ''k''-sided die rolled ''n'' times. For ''n'' statistical independence, indepen ...

. Using these, it can look for areas of higher and lower occurrences of phenomena than expected. Results are output into a variety of formats, including ESRI

Shapefile The shapefile format is a geospatial vector data format for geographic information system (GIS) software. It is developed and regulated by Esri as a mostly open specification for data interoperability among Esri and other GIS software product ...

HTML Hypertext Markup Language (HTML) is the standard markup language for documents designed to be displayed in a web browser. It defines the content and structure of web content. It is often assisted by technologies such as Cascading Style Sheets ( ...

, and

KML Keyhole Markup Language (KML) is an XML notation for expressing geographic annotation and visualization within two-dimensional maps and three-dimensional Earth browsers. KML was developed for use with Google Earth, which was originally named Key ...

History

SaTScan was developed by a group of epidemiologists and statisticians led by

, a Swedish biostatistician professor of medicine at

Harvard Harvard University is a private Ivy League research university in Cambridge, Massachusetts, United States. Founded in 1636 and named for its first benefactor, the Puritan clergyman John Harvard, it is the oldest institution of higher lear ...

Medical School. Version 1.0 of the software was first released in 1997 and has since become a widely used tool in the field of public health research and practice. SaTScan was developed in response to a growing need for sophisticated tools to analyze disease outbreaks. Before the development of SaTScan, few tools were available that could effectively analyze the spatial and temporal patterns of disease, making it difficult for public health authorities to respond effectively to outbreaks. Since its release, SaTScan has been used in many public health research studies, including infectious diseases, cancers, and other conditions. Public health authorities and disease surveillance systems have also adopted the software in many countries, and it has broad applications for other types of data. SaTScan was used extensively by researchers during the

COVID-19 pandemic The COVID-19 pandemic (also known as the coronavirus pandemic and COVID pandemic), caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), began with an disease outbreak, outbreak of COVID-19 in Wuhan, China, in December ...

Applications

Epidemiology

SaTScan was originally developed for epidemiology and public health. Since its release, SaTScan has been used in many public health research studies involving GIS, including infectious diseases, cancers, and other conditions. Public health authorities and disease surveillance systems have also adopted the software in many countries.

Agriculture

SaTScan can identify areas of high pest or disease risk, informing crop and livestock management and disease control efforts.

Astronomy

SaTScan can also be adapted and applied to certain astronomical studies, particularly those that involve analyzing spatial and temporal patterns in astronomical data. For example, SaTScan could identify clustering patterns in the distribution of galaxies or other astronomical objects, such as stars.

Criminology

SaTScan can identify hot spots and patterns in crime data, which can assist law enforcement agencies in allocating resources and developing crime reduction strategies.

Environmental monitoring

SaTScan can identify areas of environmental concern, such as high levels of air pollution or water contamination.

Wildlive surveillance

SaTScan can identify areas of high risk for wildlife diseases, which can inform disease management and conservation efforts.

References

{{Geography topics Free GIS software Spatial analysis Health informatics Public health
SaTScan official website