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Sample sizes and statistical methods in interventional studies on individuals with spinal cord injury: A systematic review

AIM: Prevalence and incidence of spinal cord injury (SCI) are low. However, sample sizes have not been systematically examined yet, although this might represent useful information for study planning and power considerations. Therefore, our objective was to determine the median sample size in clinic...

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Autores principales: Zimmermann, Georg, Bolter, Lisa‐Maria, Sluka, Ronny, Höller, Yvonne, Bathke, Arne C., Thomschewski, Aljoscha, Leis, Stefan, Lattanzi, Simona, Brigo, Francesco, Trinka, Eugen
Formato: Online Artículo Texto
Lenguaje:English
Publicado: John Wiley and Sons Inc. 2019
Materias:
Acceso en línea:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6771853/
https://www.ncbi.nlm.nih.gov/pubmed/31231977
http://dx.doi.org/10.1111/jebm.12356
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author Zimmermann, Georg
Bolter, Lisa‐Maria
Sluka, Ronny
Höller, Yvonne
Bathke, Arne C.
Thomschewski, Aljoscha
Leis, Stefan
Lattanzi, Simona
Brigo, Francesco
Trinka, Eugen
author_facet Zimmermann, Georg
Bolter, Lisa‐Maria
Sluka, Ronny
Höller, Yvonne
Bathke, Arne C.
Thomschewski, Aljoscha
Leis, Stefan
Lattanzi, Simona
Brigo, Francesco
Trinka, Eugen
author_sort Zimmermann, Georg
collection PubMed
description AIM: Prevalence and incidence of spinal cord injury (SCI) are low. However, sample sizes have not been systematically examined yet, although this might represent useful information for study planning and power considerations. Therefore, our objective was to determine the median sample size in clinical trials on SCI individuals. Moreover, within small‐sample size studies, statistical methods and awareness of potential problems regarding small samples were examined. METHODS: We systematically reviewed all studies on human SCI individuals published between 2014 and 2015, where the effect of an intervention on one or more health‐related outcomes was assessed by means of a hypothesis test. If at least one group had a size <20, the study was classified as a small sample size study. PubMed was searched for eligible studies; subsequently, data on sample sizes and statistical methods were extracted and summarized descriptively. RESULTS: Out of 8897 studies 207 were included. Median total sample size was 18 (range 4‐582). Small sample sizes were found in 167/207 (81%) studies, resulting limitations and implications for statistical analyses were mentioned in 109/167 (65%) studies. CONCLUSIONS: Although most recent SCI trials have been conducted with small samples, the consequences on statistical analysis methods and the validity of the results are rarely acknowledged.
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spelling pubmed-67718532019-10-07 Sample sizes and statistical methods in interventional studies on individuals with spinal cord injury: A systematic review Zimmermann, Georg Bolter, Lisa‐Maria Sluka, Ronny Höller, Yvonne Bathke, Arne C. Thomschewski, Aljoscha Leis, Stefan Lattanzi, Simona Brigo, Francesco Trinka, Eugen J Evid Based Med Articles AIM: Prevalence and incidence of spinal cord injury (SCI) are low. However, sample sizes have not been systematically examined yet, although this might represent useful information for study planning and power considerations. Therefore, our objective was to determine the median sample size in clinical trials on SCI individuals. Moreover, within small‐sample size studies, statistical methods and awareness of potential problems regarding small samples were examined. METHODS: We systematically reviewed all studies on human SCI individuals published between 2014 and 2015, where the effect of an intervention on one or more health‐related outcomes was assessed by means of a hypothesis test. If at least one group had a size <20, the study was classified as a small sample size study. PubMed was searched for eligible studies; subsequently, data on sample sizes and statistical methods were extracted and summarized descriptively. RESULTS: Out of 8897 studies 207 were included. Median total sample size was 18 (range 4‐582). Small sample sizes were found in 167/207 (81%) studies, resulting limitations and implications for statistical analyses were mentioned in 109/167 (65%) studies. CONCLUSIONS: Although most recent SCI trials have been conducted with small samples, the consequences on statistical analysis methods and the validity of the results are rarely acknowledged. John Wiley and Sons Inc. 2019-06-23 2019-08 /pmc/articles/PMC6771853/ /pubmed/31231977 http://dx.doi.org/10.1111/jebm.12356 Text en © 2019 The Authors. Journal of Evidence‐Based Medicine published by Chinese Cochrane Center, West China Hospital of Sichuan University and John Wiley & Sons Australia, Ltd This is an open access article under the terms of the http://creativecommons.org/licenses/by-nc/4.0/ License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited and is not used for commercial purposes.
spellingShingle Articles
Zimmermann, Georg
Bolter, Lisa‐Maria
Sluka, Ronny
Höller, Yvonne
Bathke, Arne C.
Thomschewski, Aljoscha
Leis, Stefan
Lattanzi, Simona
Brigo, Francesco
Trinka, Eugen
Sample sizes and statistical methods in interventional studies on individuals with spinal cord injury: A systematic review
title Sample sizes and statistical methods in interventional studies on individuals with spinal cord injury: A systematic review
title_full Sample sizes and statistical methods in interventional studies on individuals with spinal cord injury: A systematic review
title_fullStr Sample sizes and statistical methods in interventional studies on individuals with spinal cord injury: A systematic review
title_full_unstemmed Sample sizes and statistical methods in interventional studies on individuals with spinal cord injury: A systematic review
title_short Sample sizes and statistical methods in interventional studies on individuals with spinal cord injury: A systematic review
title_sort sample sizes and statistical methods in interventional studies on individuals with spinal cord injury: a systematic review
topic Articles
url https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6771853/
https://www.ncbi.nlm.nih.gov/pubmed/31231977
http://dx.doi.org/10.1111/jebm.12356
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