By: Brian Wells, MS4, MPH

It’s a known truth of any research project: If one wants strong conclusions, one must be able to back them up with equally strong evidence.

Fortunately for researchers, an entire field dedicated to such evidence is available to us. That field is biostatistics.  However, even experienced researchers sometimes shudder at the thought of doing long calculations and setting up statistical models.

Enter Biostats Calculator for the iPhone and iPad.  The Biostats Calculator app allows anyone to quickly and accurately make statistics calculations to arrive at a decision.

For example, let’s say you are sitting around the conference table debating on whether studying drug X’s clinical and economic impact would be feasible. How many people would you need? How big of a difference are you looking for? What’s the sensitivity of test A versus test B? How would looking at a proportion versus a value alter the outcome?

Biostats Calculator can do all of these without the cost and complexity of a desktop statistics package.

Unpaired t 1 Unpaired t 2 Sample size Diagnostic test

iTunes blurb:

“Biostats Calculator provides a comprehensive collection of biostatistical calculations. It is designed to provide easy access to the most common tests without resorting to a complex desktop statistics package. It also includes a sample size calculator for epidemiological studies, and can measure the utility and power of diagnostic tests.”

Tests included in the package are:

  • Odds Ratio
  • Relative Risk
  • Chi-Squared and Fisher Exact Test
  • Unpaired t-test
  • Mann-Whitney U Test
  • One-way ANOVA test
  • Paired t-test
  • Wilcoxon signed-rank test
  • Pearson correlation
  • Spearman rank correlation
  • Sample size calculator
  • Diagnostic test utility

Software strengths:

  • Without a doubt, this software is great for quick calculations and small datasets.
  • It provides a good sample of the normal parametric and non-parametric tests typically used in statistics.
  • For most scenarios, the included tests will be sufficient to assess the data.
  • I can see this software being a boon to students learning biostatistics or to those needing to make quick calculations without access to a full blown statistics package like STATA or SPSS.
  • To its credit, Biostats Calculator does provide a short tutorial with every test explaining the test’s purpose and how to interpret the outcome.

Software weaknesses:

  • Entering large amounts of data would be too time-consuming.
  • The program should incorporate a way to upload data via a web interface.
  • Additionally, it would be good to include other tests such as Durbin-Watson or generalized estimating equations as these can be important in building models and assessing the accuracy of statistical conclusions.

Overall rating:

  • I would be hard pressed to rate this software as a must-buy.
  • It will find use among those learning biostatics as it provides not only the tests and calculations but an explanation of each test and its applicability.  However, for serious researchers, this software is too limited in terms of tests and data entry.
  • There should be an easy way to test for things such as autocorrelation and to rapidly enter and store datasets and to maintain multiple sets of stored data for comparison.


For learning or basic statistics use, this package represents a good deal and an easy way to quickly learn some of the basics about statistics. However, for now, professional researchers should stick to desktop tools which provide more features and ways to analyze and display data.

Price: $9.99

BioStats Calculator on iTunes: