B. Non-Randomised controlled trials
CategoryNumber of studiesTotal participants
(intervention group)
Actual (A) or simulated (S) travelAthlete specificMethodological qualityConsistencyDirectnessPrecisionPublication biasTotal
GRADE rating
Melatonin 2 34 (34)PoorVery low
Cardinali, et al 30
Manfredini, et al 39
22 (22)
12 (12)
Both studies no control group, clinical heterogeneity, methodological heterogeneity(The evidence answers the review question)Effect size andCIs not reported, no control group
Sedatives 1 17 (9)Poor
Reilly, et al 40 17 (9)AMixed
(gymnasts and support staff in one group)
9/28Mixed gymnasts and support staff into one group(The evidence answers the review question)Mixed athletes and non-athletesVery low
Stimulants 0
Melatonin analogues 1 8 (8)Moderate*/†*Low
Nickelsen, et al 45 SNo19/28Although small sample size, well described methodology and reported results(The evidence answers the review question)Effect size andCIs not reported
Glucocorticoids 0
Antihistamines 0
TOTAL 4 59 (51)
  • *.Some problems

  • †No serious problems.

  • ‡Major problems

  • §All athlete specific studies have small sample sizes that may lead to publication bias.

  • GRADE, Grading of Recommendations, Assessment, Development and Evaluation; RCTs, randomised controlled trials; RoB, risk of bias.