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Table 3 Grading of Recommendations Assessment, Development and Evaluation (GRADE) analysis: quality of the overall literature pool assessing melatonin for the promotion of healthy sleep patterns

From: The effectiveness of melatonin for promoting healthy sleep: a rapid evidence assessment of the literature

Category Number of participants completed (Number of studies) Confidence in estimate of Effect GRADE1 Magnitude of estimate of Effect GRADE2 Safety GRADE3 Strength of the Recommendation4
Shift Workers 300 (8) C ND +1 None
Jet Lag 972 (8) B ND +1 Weak, in favor
Insomnia 845 (4) B ND +1 Weak, in favor
Healthy Volunteers      
Initiation of Sleep/Sleep Efficacy 82 (7)* B ND 0 Weak, in favor
Occurrence of Daytime Sleepiness/Somnolence 108 (5)* B ND 0 Weak, in favor
Phase Shift Changes 49 (5) C ND 0 None
  1. *2 Studies [50, 51] mentioned in both groups.
  2. There are four major domains that comprise the core of the modified GRADE methodology:
  3. 1Categorized as A (High; further research is very unlikely to change confidence in the estimate of effect); B (Moderate; further research is likely to have an important impact on confidence in the estimate of effect and may change the estimate); C (Low; further research is very likely to have an important impact on confidence in the estimate of effect and is likely to change the estimate)or; D (Very Low; any estimate of effect is very uncertain).
  4. 2Categorized as none (<0.2), small (0.2 – 0.5), moderate (0.5 – 0.8), large (>0.8) or not described (ND; authors did not describe or report effect size for this review’s outcomes of interest due to the lack of author reporting).
  5. 3Dependent on the frequency and severity of adverse events and interactions; as +2 (appears safe with infrequent adverse events and interactions); +1 (appears relatively safe but with frequent but not serious adverse events and interactions); 0 (safety not well understood or conflicting); −1 (appears to have safety concerns that include infrequent but serious adverse events and/or interactions) or; −2 (has serious safety concerns that include frequent and serious adverse events and/or interactions).
  6. 4Strength of the recommendation can be determined using the following categories and criteria: Strong recommendation in favor of or against (very certain that benefits do, or do not, outweigh risks and burdens); No recommendation (no recommendations can be made) or; Weak recommendation in favor of or against (benefits and risks and burdens are finely balanced, or appreciable uncertainty exists about the magnitude of benefits and risks).