Is clustering accounted for in studies published in periodontology and oral implantology specialty journals?
clustering
journals
oral implantology
periodontology
statistical analysis
Journal
Journal of periodontology
ISSN: 1943-3670
Titre abrégé: J Periodontol
Pays: United States
ID NLM: 8000345
Informations de publication
Date de publication:
08 2023
08 2023
Historique:
revised:
27
01
2023
received:
07
11
2022
accepted:
11
02
2023
medline:
18
8
2023
pubmed:
18
2
2023
entrez:
17
2
2023
Statut:
ppublish
Résumé
Clustering effects can be encountered in periodontology and implant dentistry research. The aim of this study was to identify studies with clustering effects published in periodontology and oral implantology specialty journals and to assess the frequency by which clustered designs are correctly accounted for in the statistical analysis. Ten periodontology and oral implantology journals were searched to identify studies with clustering effects published between January 1, 2019 and July 31, 2021. Descriptive statistics and frequency distributions were calculated. Associations between the correct statistical handling of clustering effects and study characteristics were explored. A total of 695 studies were included of which 45.0% correctly accounted for clustering effects in the statistical analysis. Certain journals (p < 0.01) and animal studies (p < 0.01) had lower odds of correctly accounting for clustering effects in the statistical analysis, whereas per unit increase in impact factor (p < 0.001), involvement of statistician (p < 0.001) and when the study design included either repeated measures only (p < 0.01) or both clustering and repeated measures (p < 0.001) had higher odds. The most commonly used tests were the mixed models or generalized estimating equations (64.2%). Greater awareness of the importance of accounting for clustering effects is required to prevent incorrect inferences being drawn. Incorrect inferences are related to lack of data independence and the artificial inflation of the sample size which can result in statistically significant results which are not genuine. This issue can be further exaggerated in combination with publication bias.
Sections du résumé
BACKGROUND
Clustering effects can be encountered in periodontology and implant dentistry research. The aim of this study was to identify studies with clustering effects published in periodontology and oral implantology specialty journals and to assess the frequency by which clustered designs are correctly accounted for in the statistical analysis.
METHODS
Ten periodontology and oral implantology journals were searched to identify studies with clustering effects published between January 1, 2019 and July 31, 2021. Descriptive statistics and frequency distributions were calculated. Associations between the correct statistical handling of clustering effects and study characteristics were explored.
RESULTS
A total of 695 studies were included of which 45.0% correctly accounted for clustering effects in the statistical analysis. Certain journals (p < 0.01) and animal studies (p < 0.01) had lower odds of correctly accounting for clustering effects in the statistical analysis, whereas per unit increase in impact factor (p < 0.001), involvement of statistician (p < 0.001) and when the study design included either repeated measures only (p < 0.01) or both clustering and repeated measures (p < 0.001) had higher odds. The most commonly used tests were the mixed models or generalized estimating equations (64.2%).
CONCLUSIONS
Greater awareness of the importance of accounting for clustering effects is required to prevent incorrect inferences being drawn. Incorrect inferences are related to lack of data independence and the artificial inflation of the sample size which can result in statistically significant results which are not genuine. This issue can be further exaggerated in combination with publication bias.
Identifiants
pubmed: 36799353
doi: 10.1002/JPER.22-0653
doi:
Types de publication
Journal Article
Langues
eng
Sous-ensembles de citation
IM
Pagination
967-975Informations de copyright
© 2023 American Academy of Periodontology.
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