Ninety-five perconfidencedence intervals were calculated by using a t-statistic; p values testing the significance of the difference in prevalence between NHANES III and NHANES 1999 2000 were obtained by using a t-statistic with the combined standard error.
To handle missing data, multiple imputation implemented with chained equations was used to create 10 imputed datasets, using Rubin's rule to combine standard errors [ 24].
Table 2 The estimated number of badgers in each Land Class Group as calculated from the estimated mean number of badgers per social group and number of social groups and extrapolated population estimates for England and Wales combined (with standard errors, relative standard errors and 95% confidence intervals shown as appropriate).
We use the delta method (Powell 2007) in the R package msm to combine multiple standard errors and construct 95%% CIs around our final effect size estimates.
An error propagation method is used when we combine the standard errors from multiple sources without original data (e.g., the integration of standard errors from forward and inverse modeling methods).
Standard errors for the prevalence estimates were calculated by combining the standard errors in estimated mean AUDIT scores for the NZ sample and the estimated post-test probabilities of alcohol abuse or dependence for given AUDIT test scores.
These models combine standard exclusion restrictions with a requirement that each structural error enter through a "residual index" function.
Marginal models do not require any distributional assumptions beyond correctly modelling the mean (average) outcome, yet when combined with robust standard errors they can provide appropriate inferences.
The results from the COG discovery cohort and the UPDB validation cohort were combined using weighted standard errors in meta-analysis, due to differences in study design between the cohorts, to generate summary ORs (ORs) and 95% CIs.
In the analysis using the combined data set, standard errors were adjusted for non-independence between biomarkers coming from the same individual using the cluster option for clogit in STATA [ 39].
The GWAS meta-analysis was performed using the METAL program [ 18], which tests the combined effects and standard errors of effects of each common SNP across the tested populations by taking sample size and direction of genotype effects into account.
