Overall, increased leptin levels were observed in men and women following higher categories of CRP, BMI, and waist circumference (Fig. 1), with the highest concentrations of leptin seen in men and women with high CRP and BMI ≥ 30 kg/m or the upper category of waist circumference.
For all analyses we used the midpoint of each income category and calculated the mid-point of the upper category of income ($66,800) by assuming a Pareto distribution of family income per standard methodology [ 17].
These categories were based on the current EPA regulatory standard [ 38] and World Health Organization guideline value [ 39] of 10 μg/L for the lowest category and just below the previous EPA standard of 50 μg/L for the upper category.
In the upper category (91 100), 76% are equal to 100, 15% chose 95, and more than 9% are other scores in the category (92, 93, etc).
Those participants who were in the upper category of the intoxication frequency variable were considered a high risk group.
For example, the upper category of time in present military occupational specialty was adjusted from 20 to 24 months, yielding categories of ≤12 months, 13 24 months and ≥25 months.
However, from the study by Silverman et al. (2012), we obtained the median cumulative exposure value for the upper category (Silverman DT, personal communication).
Although the upper category of the intensity-weighted lifetime exposure-days suggests an increase in the relative risk, the exposure response gradient was not monotonic.
Owing to the small numbers of adenocarcinoma cases in the upper categories for number of partners, these results are given for three categories only; finer stratification by number of partners within the upper category for lifetime or regular partners did not substantially alter the results.
The main assumption is that a better model would place more participants at the extremes of the risk distribution, with the upper category having clear implications for preventive interventions.
