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VOLUME 56 , ISSUE 3 ( July-September, 2022 ) > List of Articles


Statistics Corner: Comparing Two Unpaired Groups

Kamal Kishore, Vidushi Jaswal

Keywords : Independent t-test, Student's t-test, Unequal variance, t-test Unpaired t-test, Welch's t-test

Citation Information : Kishore K, Jaswal V. Statistics Corner: Comparing Two Unpaired Groups. J Postgrad Med Edu Res 2022; 56 (3):145-148.

DOI: 10.5005/jp-journals-10028-1594

License: CC BY-NC 4.0

Published Online: 01-10-2022

Copyright Statement:  Copyright © 2022; The Author(s).


Statistical analysis comparing two groups is most frequently reported in the literature; an unpaired t-test is popular to inform results from two independent groups. The t-test is parametric and makes certain assumptions about the data. Literature, however, has shown that the t-test is robust to statistical assumptions violation. Many researchers, therefore, do not test assumptions to apply t-test. The robustness property of the t-test has certain limitations. A researcher interested in reporting results using a t-test must know the following: • What are the assumptions for an unpaired t-test? • Are assumptions essential and need to be tested? • What is robustness in the context of statistical tests? • Are there any reporting standards to report t-test results?

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