Retrospective 2,463 hospitalized patients in Spain, 265 treated with melatonin, showing lower mortality with treatment in PSM analysis, however these results are subject to immortal time bias. Authors excluded from the sample patients that died during the first 72 hours of admission without taking melatonin, and patients that started on melatonin in the last 7 days of their admittance, having completed 75% of their stay.
risk of death, 54.4% lower, RR 0.46, p < 0.001, treatment 24 of 224 (10.7%), control 53 of 224 (23.7%), NNT 7.7, odds ratio converted to relative risk, PSM.
Effect extraction follows pre-specified rules prioritizing more serious outcomes.
This study is excluded in the after exclusion results of meta
immortal time bias may significantly affect results.
Sánchez-González et al., 7/20/2021, retrospective, Spain, Europe, peer-reviewed, 4 authors.