Statistics at your fingertips

EpiTools and the 2x2 calculator are easy and free to use multi-lingual teaching and field tools which allow users to calculate key statistics such as sample sizes, test performance or relative risk. Beyond applying the underlying logic, exploratory animations and context sensitive text help users understand how the measures are calculated, how they are interpreted and what the subtle differences between the different measures are. Epidemiology made easy wherever you are – from the classroom to out in the field.


EpiTools on the App Store

EpiTools on Google Play

2x2 calculator

An innovative approach to teaching

With the 2x2 calculator the project team didn’t just want to replicate what has always been done, but had the vision to take the teaching of epidemiological methods to the next level. Hence, while we provide an easy to use online calculator for the different measures of association, we also allow users to interactively explore how each measure is calculated through explanatory animations and annotations. This helps users improve how they apply and interpret the different measures and provides them with constant opportunities to refresh their knowledge while they make use of the free online tool.

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Knowledge transfer for a global audience

To keep this tool accessible to a wide audience, we created multiple language options. Any language can be added to the app; and users can easily switch between them through a drop-down menu.

By facilitating teaching of key epidemiological concepts across language barriers the app is able to support epidemiologists working globally to improve health outcomes in humans and animals and to reduce the risk of future pandemics through regional or in-country training and capability building initiatives.

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Interactive learning

Interactive GIFs provide a visual aid for learning how values in the table are combined to derive different measures of association. Detailed interpretations are provided for each calculation and adjusted to the data entered and the choice of study type.

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On-the go-calculations

Widespread use of smart phone devices allows veterinary students, practicing veterinarians and veterinary epidemiologists to carry substantial amounts of technical information literally ‘in their back pockets’. While this has, in some ways, alleviated the need to memorise large volumes of facts and formulae, the need to understand core epidemiology topics (measures of disease frequency, measures of association, sources of error in epidemiological research and causation) remains.

The functions within in the app are organised by topic consistent with the topics delivered within the course. Users have the ability to carry out standard epidemiological calculations using a relatively simple user interface. Each function is accompanied by documentation providing details of input variables, calculation methods, supporting references for the formulae used and worked examples.

A glossary provides concise definitions of common epidemiological terms. For some glossary items animations are included to assist visual learners to better understand text descriptions provided.

The multi-lingual app is freely available in the App store.

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Stevenson M, Pfeiffer C, Mullner PMullner U, Firestone S, Wiethoelter A, Nguyen H. Tools to assist with learning, understanding and the practice of veterinary epidemiology. 16th Symposium of the International Society for Veterinary Epidemiology and Economics (ISVEE), Halifax, Canada, August 2022.