Related Experiment Video
Updated: Aug 9, 2026

Online Explorative Study on the Learning Uses of Virtual Reality Among Early Adopters
Published on: November 22, 2019
The chi-square test: its use in rehabilitation research
1SUNY at Buffalo 14214, USA.
Objective:
This report examines the impact of collecting and analyzing sequential data from the same sample using the chi-square test. Researchers in rehabilitation frequently analyze categorical data collected repeatedly from the same sample.
Design:
Simulations were conducted using the chi-square test to analyze data with correlations between pretest and posttest ranging from .20 to .80. The simulations were analyzed using the standard chi-square based on a 2 x 2 contingency table.
Results:
An incidence of type 1 errors of approximately .30 for an expected alpha of .05 was found when the correlation (serial dependence) between pretest and posttest was high (phi = .80). For simulations using an alpha = .01, the type 1 error rate was .18 for data with substantial correlation (phi = .80).
Conclusion:
Rehabilitation researchers who use the chi-square test with data collected repeatedly from the same sample risk committing a type 1 error and misinterpreting their results. Alternatives to the standard chi-square test, such as McNemar's test, should be considered when correlated data are analyzed using a 2 x 2 contingency table.
Related Concept Videos
Chi-square Analysis
The chi-square test was developed by Pearson in 1990.
The first step of performing a Chi-square analysis is to establish a null hypothesis, which assumes that there is no real...
Chi-square Distribution
Goodness-of-Fit Test
Hypothesis Test for Test of Independence
H0: The two variables (factors)...
Test for Homogeneity
Cochran's Q Test

