Among ever OC users, we studied the duration of OC use in three categories (⩽4, 5 9, and ⩾10 years), and among ever IUD users, we studied the duration in two categories (⩽4 and ⩾5 years).
Duration (in four categories) of maternal sport fish consumption was forced into the model while all other covariates were entered using a forward stepwise approach.
In contrast, when the duration is in category 3, and intensity is in category 1, the densities corresponding to the 2 highest time since cessation categories are almost coincident.
There was some misclassification when breastfeeding duration was analysed in categories.
The effect of covariates on is estimated by the regression model described in Equation 1. 1 In equation 1, is the hazard of a first birth at time t for woman i, is a vector of dummy variables capturing the duration since marriage (in categories of months), is a vector of time-dependent coefficients and a vector of explanatory variables for women i.
These parameters included age categories (<50 years, 50 75 years in 5-year intervals, and ≥75 years), diabetes duration (in quartiles), BMI categories (as presented above), previous history of hypoglycaemia or microvascular disease, number and change in OAD therapy at the time of insulin initiation, HbA1c at baseline and insulin dose (IU in quartiles) [ 12].
The primary effect measure was the adjusted difference and 95% confidence interval (CI) in QT interval duration by categories of each exposure compared to the reference category, calculated from multivariable linear regression models.
To calculate the training load, training duration in each intensity category was multiplied with the corresponding factor and summarized.
This is particularly apparent when looking at the posterior mean log odds ratio for each combination (see Table 3), which ranges from 0.83 for the pseudo-profile with intensity and duration in the lowest smoking categories, to 4.58 for the pseudo-profile with intensity and duration in the highest smoking categories.
Age-group– and duration-group specific proportions were then weighteduration-group specificf miners (black and white combined) in each age and duration category in the calculation of the standardized proportions were silicosis by year of autheny interval.
When applicable, linear or logistic regression was used to adjust for differences in diabetes duration between age categories for continuous and dichotomous outcomes, respectively.
