CONTEXT: Quantitative systematic reviews need to consider clinical, methodological and statistical heterogeneity of trials or datasets from trials before combining their results in meta-analyses, as combining results from heterogeneous datasets and/or trials will lead to meaningless results and thus should be avoided. Potential statistical heterogeneity between trials/datasets that have been considered as being clinically/methodologically homogeneous is usually investigated using I2 – test and Cochrane Q statistics.
PROBLEM: However, both, I2 – test and Cochrane Q statistics are tests with low statistical power, which gives even weaker results the smaller the number of trials/datasets is (n < 15).
SUGGESTED SOLUTION: Therefore, statistical in-between-trial heterogeneity should be assessed using the point estimate together with its 95% Confidence interval of the I2 – test. Galbraith plots are to be used to identify outlying datasets/trials, which then should be further investigated for potential effect modifiers using regression analysis.
Mickenautsch, S. (2019). SYSTEM Research note on: Recognizing statistical in-between-trials heterogeneity. Afribary. Retrieved from https://afribary.com/works/system-research-note-on-recognizing-statistical-in-between-trials-heterogeneity
Mickenautsch, Steffen "SYSTEM Research note on: Recognizing statistical in-between-trials heterogeneity" Afribary. Afribary, 26 May. 2019, https://afribary.com/works/system-research-note-on-recognizing-statistical-in-between-trials-heterogeneity. Accessed 02 May. 2024.
Mickenautsch, Steffen . "SYSTEM Research note on: Recognizing statistical in-between-trials heterogeneity". Afribary, Afribary, 26 May. 2019. Web. 02 May. 2024. < https://afribary.com/works/system-research-note-on-recognizing-statistical-in-between-trials-heterogeneity >.
Mickenautsch, Steffen . "SYSTEM Research note on: Recognizing statistical in-between-trials heterogeneity" Afribary (2019). Accessed May 02, 2024. https://afribary.com/works/system-research-note-on-recognizing-statistical-in-between-trials-heterogeneity