The overall quality of evidence for primary outcomes was "very low", the researchers concluded.
All studies had scores of methodological quality of ≥ 3/5, and no sensitivity analysis for primary outcomes was carried out for this criterion.
The final data collection for primary outcomes is estimated to occur by December 2015, the results of which are highly anticipated.
We will conduct subgroup analyses for primary outcomes comparing children (up to 12 years) to adolescents (between 13 and 18 years).
Besides, for primary outcomes, we defined a "surrogate outcome" as an outcome measuring a substitute for some other variable (e.g., a biomarker intended to substitute for a clinical endpoint) [2].
We considered 3 groups and 7 measurements for primary outcomes to obtain 80% statistical power (1-β error probability) with an α error level probability of 0.05 using analysis of variance (ANOVA) of repeated measures, within-between interaction, and a medium effect size of 0.3.
Reporting and interpretation of randomized controlled trials with statistically nonsignificant results for primary outcomes.
* Statistical significance for primary outcomes (P < 0.025).
Both studies were adequately powered (90%) for primary outcomes.
Overall, no significant differences were found for primary outcomes (figure 3).
For primary outcomes, a p-value of < 0.05 will be considered statistically significant.
