EPIDEMIOLOGY AND HEALTH DATA INSIGHTS
Methodological Paper
Nov 03, 2025 46 17

Reporting Practices in Epilepsy Research: An Overview and Tutorial

Ruslan Akhmedullin 1 * ,
Gaziz Kyrgyzbay 2,
Darkhan Kimadiev 2,
Zhasulan Utebekov 2,
Ayana Ablayeva 1
1 Department of Medicine, School of Medicine, Nazarbayev University, Astana, Kazakhstan2 Epileptology Centre, RSE Medical Centre Hospital of the President's Affairs Administration of the Republic of Kazakhstan, Astana, Kazakhstan* Corresponding Author
Epidemiology and Health Data Insights, 1(5), 2025, ehdi018, https://doi.org/10.63946/ehdi/17368
Publication date: Nov 03, 2025
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ABSTRACT

Background. This study examined the reporting practice of subgroup effects of meta-analytic research published in the leading journal of the ILAE.
Methods. We selected studies that used ratio measures and employed subgroup analyses. Subgroup differences were calculated as the difference between the log-transformed estimates over the square root of the sum of the squared standard errors. For the calculated test scores, a corresponding two-tailed p-value was calculated using the standard normal cumulative distribution function. The authors also conducted additional analyses accounting for multiple comparisons.
Results. The literature search identified 55 publications, of which 14 (25 %) were included. Neither study used a formal test to compare the subgroups. The number of reported subgroup estimates ranged from 2 to 20, and the number of pairwise comparisons ranged from 1 to 53. Overall, there were 187 comparisons, resulting in a median log difference of 0 (IQR 0.12 – 0.17) and a range from -2.92 to 2.32. The median p-value was 0.54 (IQR 0.21-0.85) with 18 (9%) comparisons showing p-values lower than the conventional significance level, whereas 6 and 21 contrasts were 0.05 < p ≤ 0.10 and 0.10 < p ≤ 0.20, respectively. Seven (4%) comparisons resulted in a p-value lower than the corrected significance level when adjusted for multiple comparisons.
Conclusion. There was a lack of compliance with the reporting guidelines. The findings from the subgroup analyses were commonly interpreted without employing a formal test. There is need to emphasize the importance of adherence to established reporting standards when presenting the subgroup effects.

KEYWORDS

Epilepsy Meta-Analysis Subgroup Analysis Reporting Bias

CITATION (Vancouver)

Akhmedullin R, Kyrgyzbay G, Kimadiev D, Utebekov Z, Ablayeva A. Reporting Practices in Epilepsy Research: An Overview and Tutorial. Epidemiology and Health Data Insights. 2025;1(5):ehdi018. https://doi.org/10.63946/ehdi/17368
APA
Akhmedullin, R., Kyrgyzbay, G., Kimadiev, D., Utebekov, Z., & Ablayeva, A. (2025). Reporting Practices in Epilepsy Research: An Overview and Tutorial. Epidemiology and Health Data Insights, 1(5), ehdi018. https://doi.org/10.63946/ehdi/17368
Harvard
Akhmedullin, R., Kyrgyzbay, G., Kimadiev, D., Utebekov, Z., and Ablayeva, A. (2025). Reporting Practices in Epilepsy Research: An Overview and Tutorial. Epidemiology and Health Data Insights, 1(5), ehdi018. https://doi.org/10.63946/ehdi/17368
AMA
Akhmedullin R, Kyrgyzbay G, Kimadiev D, Utebekov Z, Ablayeva A. Reporting Practices in Epilepsy Research: An Overview and Tutorial. Epidemiology and Health Data Insights. 2025;1(5), ehdi018. https://doi.org/10.63946/ehdi/17368
Chicago
Akhmedullin, Ruslan, Gaziz Kyrgyzbay, Darkhan Kimadiev, Zhasulan Utebekov, and Ayana Ablayeva. "Reporting Practices in Epilepsy Research: An Overview and Tutorial". Epidemiology and Health Data Insights 2025 1 no. 5 (2025): ehdi018. https://doi.org/10.63946/ehdi/17368
MLA
Akhmedullin, Ruslan et al. "Reporting Practices in Epilepsy Research: An Overview and Tutorial". Epidemiology and Health Data Insights, vol. 1, no. 5, 2025, ehdi018. https://doi.org/10.63946/ehdi/17368

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