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Review
. 2024 Jan 26;10(3):e25131.
doi: 10.1016/j.heliyon.2024.e25131. eCollection 2024 Feb 15.

On the use of post-hoc tests in environmental and biological sciences: A critical review

Codjo Emile Agbangba  1   2 , Edmond Sacla Aide  1   3 , Hermann Honfo  1 , Romain Glèlè Kakai  1
Affiliations
Review

On the use of post-hoc tests in environmental and biological sciences: A critical review

Codjo Emile Agbangba et al. Heliyon. .

Abstract

Post-hoc comparison procedures are commonly used to determine which group means differ after a significant analysis of variance (ANOVA). Several post-hoc tests have been proposed, but their use requires certain assumptions to be met, such as normality, equality of variance, and balanced group size. This review examined the statistical literature on post-hoc tests and their use in the environmental and biological sciences. Through this review, we found that post-hoc tests are effective but often inadequately used in these sciences. We conducted a search of reputed search engines to identify articles in which post-hoc tests were used and found ten post-hoc tests used in the environmental and biological literature. Tukey HSD (30.04%), Duncan's (25.41%) and Fisher's LSD (18.15%) were the most commonly used post-hoc tests over the past 20 years, whereas the Games-Howell (1.13%), Holm-Bonferroni (1.25%), and Scheffe's tests (2.25%) were the least used. The choice of post-hoc test depended on the statistical method used prior. In addition, the assumptions of applying post-hoc tests were not always verified. In fact, the normality condition was mostly only checked in the cases of Tukey HSD, Duncan's, and Fischer's LSD tests, and equality of variance was often met for the Tukey HSD, Duncan's, Fischer's LSD, and Bonferroni tests. This review opens a new avenue for comparing post-hoc test performance in ANOVA using linear or generalised mixed effect models.

Keywords: Assumptions; Effective use; Multiple comparison tests; Review.

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Conflict of interest statement

The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: Codjo Emile Agbangba reports was provided by University of Abomey-Calavi. Codjo Emile AGBANGBA reports a relationship with University of Abomey-Calavi Laboratory of Biomathematics and Forest Estimations that includes: employment. There is no conflict of interest If there are other authors, they declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.

Figures

Figure 1
Figure 1
Study identification.
Figure 2
Figure 2
Relative use of post-hoc tests regarding size of groups. Bonferroni : Bonferroni test; Ducan: Duncan test ; Dunnett: Dunnett's test; Dunns : Dunn's test ; GH : Games-Howell test ; HB : Holm-Bonferroni test ; Fischer LSD : Fisher's Least Significant Difference test ; Scheffé : Scheffé's test ;SNK : Newman-Keuls test; Tukey HSD : Tukey Honestly Significant Difference.
Figure 3
Figure 3
Correspondence analysis biplot of post-hoc procedures and statistical methods. Bonf: Bonferroni; Duc:Duncan ; Dun_c: Dunnett's correction ; Dunns : Dunn's test ; GH : Games-Howell ; HB : Holm-Bonferroni ; LSD : Fisher's Least Significant Difference ; Schf : Scheffé ;SNK : Newman-Keuls; Tukey HSD GLM: Generalized Linear Models; Anova: Analysis of variance; LMEM: Linear Mixed Effect Models; t-test: Test t de Student; KW: Kruskal Wallis test; MW: Mann Whitney test.
Figure 4
Figure 4
Correspondence analysis biplot of post-hoc procedures and domain of use. Genetics: Gene; Agriculture: Agri; Biotechnology: Biotech; Breeding and animal health: BAH; Dentistry: Dent; Ecology: Eco; Medicine: Med; Nutrition and food security: NFS; Others: Others; Soil science and Plant nutrition: SPN; Sport: Sports.
Figure 5
Figure 5
Proportion of articles in which the application conditions are checked regarding the test. Bonf: Bonferroni; Duc: Duncan; Dun_c: Dunnett's correction; Dun : Dunn's test; GH : Games-Howel; HB : Holm-Bonferroni; LSD : Fisher's Least Significant Difference; Schf : Scheffé; SNK : Newman-Keuls; Tukey HSD.
Figure 6
Figure 6
Proportion of articles in which the application conditions are checked regarding the domain.
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References

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