Volume 9, Number 10—October 2003
Research
Escherichia coli O157 Exposure in Wyoming and Seattle: Serologic Evidence of Rural Risk
Table 2
Age, gender, history EIA value distribution in each population study, and median and range of OD for the EIA readingsa
Population A | Population B | Population C | |
---|---|---|---|
Characteristics of populations |
N =485 |
N =196 |
N =104 |
Age (y)
Mean (SD) |
57 (15) |
45 (12) |
45 (12) |
Male: female (not reported) |
225:260 |
56:71 (69) |
56:46 (2) |
OD (EIA units)
Least squares mean |
0.356b |
0.328c |
0.310 |
Median (range) |
0.348 (0.185–1.115) |
0.328 (0.149–0.522) |
0.312 (0.222–0.441) |
EIA, 80th percentile N+ (%) EIA, 90th percentile N+ (%) | 107 (22.0%) 60 (12.4%) | 40 (20.4%) 19 (9.7%) | 5 (4.8%) 2 (1.9%) |
aEIA, enzyme immunoassay; OD, optical density; SD, standard deviation.
bp<0.001, population A (Star Valley) vs. either Casper or Seattle.
cp< 0.05, population C (Seattle) vs. population B (Casper).