Statistical analysis
As pre-defined in MAMPED, primary analysis compared DM+PE+ vs. DM+PE-.
Secondary analyses compared ‘uncomplicated’ T1DM (DM+PE-) with
non-diabetic women (DM-). Results were expressed as means ± SD (Tables 1
& 2) or SEM (Figures 1-2). Groups were compared using unpaired
Student’s t tests for continuous measures and \(\chi^{2}\) test for
categorical measures; unpaired tests were used because of differential
sample attrition. Analyses of repeated measures used Friedman’s test.
Logistic regression, with and without covariate adjustments, was used to
estimate the probability of women with T1DM developing PE based on
clinical characteristics and biomarker values. The following covariates
were selected based on differences at the time of visit, and/or their
known associations with vitamin D metabolism: BMI, HbA1c, and total
adiponectin.37 All tests were two-tailed, with
p<0.05 considered significant. Statistical analyses were
performed using SPSS software, version 22 (IBM Corp, Armonk, NY).