This study uses long-term daily sediment records (12 51 years) from 5 unit-source watersheds in central Texas to examine the role of large infrequent erosion events in the makeup of the overall soil loss record.
However, the results of this study may not be generalizable to the entire U.S. population due to the specific demographic makeup of the study population, the particularly high rates of childhood overweight and obesity in CHAMACOS (Ogden et al. 2012), and the relatively high child PBDE concentrations in California (Windham et al. 2010).
Survival bias may therefore have impacted the makeup of the study sample in ways that ultimately impacted the distribution of cognitive function and its association with DR. A prospective study that includes detailed assessments of both retinopathy severity and cognitive function may pick up where this study leaves off and help provide clarity on these relationships.
Of screened individuals, 86.1% were female and 95.1% were non-Hispanic white, reflecting the racial makeup of the study area.
The different characteristics of the VA cohort may limit generalizability to community nursing homes, but the inclusion of the VA cohort also help complement the gender and racial makeup of the study sample.
The reasons for these discrepancies in results could be numerous including sample size, duration and mode of intervention (supplementation, injection, fortification, or...) and dosages used, baseline values of 25(OH D and also of the other variables (glucose, lipids and so on), method of vitamin D assessment (RIA, CPBA, CL or HPLC) and finally genetic makeup of the study population.
In our national study, we found persistent racial disparities across income categories, but this may be the result of differences in methodology in the estimation of race-based risks or in the demographic makeup of the different study areas.
Although the prevalence of NAFLD varies among studies due to the different sensitivities of the instruments used and the ethnic makeup of the populations studied, there is no doubt that the incidence of NAFLD is increasing to epidemic proportions, especially in developing countries.
Two national-level studies reported that the PM2.5 mortality association differed depending on the chemical makeup of PM2.5, but neither study estimated constituent-specific associations with mortality (Bell et al. 2009; Franklin et al. 2008).
We performed propensity matching to identify comparator DM and non-DM groups that were similar in age, sex, and CAD risk factors but, in doing so, altered the makeup of the initial overall study group.
