Those people in whom diabetes will develop simply have insulin sensitivity, mainly in the lowest population quartile (29).
In fully adjusted logistic models, women with PFOA ≥ 5.7 ng/mL [fourth (highest) population quartile] were more likely to report current treated thyroid disease [odds ratio (OR) = 2.24; 95% confidence interval (CI), 1.38 3.65; p = 0.002] compared with PFOA ≤ 4.0 ng/mL (quartiles 1 and 2); we found a near significant similar trend in men (OR = 2.12; 95% CI, 0.93 4.82; p = 0.073).
The 33 municipalities surrounding Belo Horizonte were first grouped according to population quartiles.
Population quartiles, based on a propensity model, were developed to address these imbalances.
For each of the resulting 15 psychosocial variables, scores were divided into population quartiles and the lower and upper quartile populations were used for comparisons in logistic regression (see below).
Figures 4(a) and 4(c) contain curves which estimate the underlying population quartiles for the t-test distributions as a function of signal intensity for datasets 10a and 10e.
The primary explanatory variables of interest, PFOA and PFOS, were analyzed as both continuous and categorical variables (study population quartiles and ventiles, with the lowest percentile group used as referent category).
Figures 3(a) and 3(c) contain curves which estimate the underlying population quartiles for the p-value distributions as a function of signal intensity for datasets 10a and 10e.
Multivariable analysis was performed using linear regression, adjusting for age (quartiles: ≤ 40, 41 47, 47 53 and 54+), gender (male or female), race/ethnicity (White, Black, Hispanic, Asian/other), smoking history (nonsmokers, ex-smokers, and current smokers) and weight (study population quartiles, ≤ 66 kg, 67 78 kg, 79 88.5 kg and ≥ 88.5 kg).
Associations were slightly stronger, but for consistency, we reported the results based on overall-population quartiles.
Finally, Poisson regression was used to test whether each of the density measures was associated with cancer risk in this population by quartile of density, and also grouping the two lower and two upper quartiles in order to improve the stability of the estimates.
