19 20 21 22 23 Studies that expressed substratified risk estimates by age, location, season, sex, and type of stroke rather than an overall risk estimate were pooled separately.
For case control studies, we found that a 100 μg per day increment of dietary folate intake led to a 5% decrease of breast cancer risk (pooled OR=0.95, 95% CI=0.92 0.98) under random-effects model when the study-specific estimate was pooled, and marginal publication bias was found (Egger's test, P=0.045).
13 We used a staged approach to meta-analysis, with single-city estimates pooled within WHO region prior to the pooled single-city and selected multicity estimates being pooled to produce a global estimate and WHO region-specific summary estimates.
If there was a moderate to high heterogeneity, correlation was explored, and if positive, a HSROC was estimated by principal component of positive MCMC estimations[ 39] and plotted, if negative or zero summary estimates were pooled without HSROC [ 39].
This "borrowing strength" translates into higher sample size depending on the magnitude of the "pooling factor" which represents the degree to which sub-parameter estimates are pooled together from hyper-parameter estimates of φ, rather than estimated independently from each phylogeographic dataset [ 56].
When estimates were pooled in a meta-analysis of 34 case-control studies of non-smokers, a pooled relative risk of 1.2 (95% CI 1.1-1.4) was observed, although only seven out of 34 studies reporting significantly elevated risk [ 6].
Study-specific relative risk estimates were pooled using random-effects or fixed-effects models.
The number of gonads per polyp, the number of oocytes/ova per gonad and the product of these two estimates were pooled between weeks 1 through 4 (pre-spawning samples).
The mean proficiency estimates were pooled across these 20 imputed values according to Rubin ([1987]).
The mean proficiency estimates were pooled over 100 imputed values according to Rubin ([2003]), whereas the regression estimates were pooled over M = 5 imputed values according to Rubin ([1987]).
