Data reproducibility issues and their potential impact on conclusions from evidence syntheses of randomized controlled trials in sleep medicine.

In this study, we examined the data reproducibility issues in systematic reviews in sleep medicine. We searched for systematic reviews of randomized controlled trials published in sleep medicine journals. The metadata in meta-analyses among the eligible systematic reviews were collected. The original sources of the data were reviewed to see if the components used in the meta-analyses were correctly extracted or estimated. The impacts of the data reproducibility issues were investigated. We identified 48 systematic reviews with 244 meta-analyses of continuous outcomes and 54 of binary outcomes. Our results suggest that for continuous outcomes, 20.03% of the data used in meta-analyses cannot be reproduced at the trial level, and 43.44% of the data cannot be reproduced at the meta-analysis level. For binary outcomes, the proportions were 14.14% and 40.74%. In total, 83.33% of the data cannot be reproduced at the systematic review level. Our further analysis suggested that these reproducibility issues would lead to as much as 6.52% of the available meta-analyses changing the direction of the effects, and 9.78% changing the significance of the P-values. Sleep medicine systematic reviews and meta-analyses face serious issues in terms of data reproducibility, and further efforts are urgently needed to improve this situation.