The mean age, nutritional status and gender of cases and controls, were similar (table 1).
2) Demographics: the age and gender of cases did not differ significantly between 2008 and 2009.
Two of the case control studies 17 18 used matching of age and/or gender of cases and controls to reduce confounding by these factors in the design stage.
The were no statistically significant differences in mean age and gender of cases excluded due to a lack of follow-up information, those participants lost to follow up and the participants remaining in the cohort.
Following adjustment for multiple confounders (age, gender, complexity of case, and skeletal patterns), the final deband score (ABO-OGS) was similar for both groups (23.8 for surgical group versus 22.5 for non-surgical group).
Gender distribution of the birth defects was 54.9% (535 cases) in male, 38.7% in female (378 cases), 0.6% in ambiguous (6 cases), and gender of 57 cases (5.8%) could not be recognized.
Note: Details regarding the gender of one case of ABI due to haemorrhage were not provided.
Since epigenetic marks may be also dependent on the gender, we additionally matched the gender ratio of cases and controls of the replication cohort to the ratio of the screening cohort, leading to significance of the same CGIs shown above.
Age, gender of all cases, and operations performed on the cardiac case group were recorded.
Stallions, geldings and mares were represented in the controls, while the gender of the cases was unknown.
