Associations of type-2 diabetes and hemoglobin A1c (HbA1c) with untransformed and log-transformed urinary bisphenol A (BPA), adjusted for urinary creatinine (natural spline (restricted cubic spline) with four degrees of freedom (knots at 25^th, 50^th, and 75^th percentiles)), age, age², gender, race-ethnicity, education, household income, body mass index, waist circumference, and smoking status.

<p>The solid line indicates the smoothing trends estimated from the natural spline (restricted cubic spline) with four degrees of freedom (knots at 25^th, 50^th, and 75^th percentiles), and the dotted lines indicate its 95% confidence intervals.