We performed duplicate linkage analyses using the variance component model (VCM) using SOLAR program [23] (see Materials and Methods), because of the robustness of this method in such a complex setting [24], and a regression linkage method using MERLIN program [25] (Regress, see Materials and Methods), which yielded overall comparable results.
Coefficients of variation for duplicate serum/plasma aliquots included in all laboratory sample batches were calculated by using the variance components model of SAS software (PROC VARCOMP; SAS Institute, Inc., Cary, North Carolina) for the 3 types of quality control samples: NIST level 1, NIST level 2, and each cohort quality control.
Then, the frailties associated with these two traits were calculated for the offspring population, using the variance component models defined in Equations 2 and 3.
Using the variance partitioning, the model also found high similarity in the pattern of hospitalization between men and women.
Evaluation of the genetic contribution to the phenotypes was performed by estimation of the heritability using the variance-component model [83].
2006 index of relative socio-economic advantage/disadvantage, Standard error, Explained 'between practice variance using the variance in the empty model as reference.
ICCs are calculated using the variance estimates obtained by modeling the average bilateral skin temperature readings using a mixed effects model.
Collinearity was examined in the final model using the variance inflation factor (VIF).
Covariates were analyzed for multicollinearity using the variance inflation factor, and the model fit was checked with the Hosmer and Lemeshow Goodness-of-Fit test.
The only case of substantial collinearity found when testing the models using the variance inflation factor (VIF) was between the variables for mother and father viewing TV advertisements.
