We provide biostatistics expertise for a number of NIEHS and NTP researchers, as well as researchers at universities and other government agencies who are conducting research related to the mission of the NIEHS. In these collaborations, we provide advice about study design, analyze data, interpret statistical results, and participate in writing papers for publication. We collaborated with NIEHS and extramural researchers who are mining survey data to discover associations between environmental exposures and disease. In one study, we examined associations in women between markers of autoimmunity (antinuclear antibodies (ANA)) and hormonal status and reproductive history. We observed that ANA was increased in women who had had at least one child, but was not further increased with the number of children. Use of hormones through contraceptives or estrogen therapy was not associated with ANA prevalence. In other retrospective data-mining studies of surgical treatment of coronary artery disease, we found that thrombosis is more likely several years after a stent is placed in a coronary artery compared to simply expanding the diameter of the artery through angioplasty. In a separate investigation, we found that stents that slowly release drugs as associated with fewer adverse effects than bare metal stents. Finally, in a survey of U.S. research institutions, we characterized policies for providing compensation to research participants who are injured as a result of the research procedures.