摘要:

We explored the relation between various potential sources of maternal periconceptional pregnancy exposures to pesticides and congenital anomalies in offspring. Data were derived from a case-control study of fetuses and liveborn infants with orofacial clefts, neural tube defects, conotruncal defects, or limb anomalies, among 1987–1989 California births and fetal deaths. We conducted telephone interviews with mothers of 662 (85% of eligible) orofacial cleft cases, 265 (84%) neural tube defect cases, 207 (87%) conotruncal defect cases, 165 (84%) limb cases, and 734 (78%) nonmalformed controls. The odds ratio (OR) estimates did not indicate increased risk for any of the studied anomaly groups among women whose self-reported occupational tasks were considered by an industrial hygienist likely to involve pesticide exposures. Paternal occupational exposure to pesticides, as reported by the mother, revealed elevated ORs for only two of the cleft phenotypes {OR = 1.7 [95% confidence interval (CI) = 0.9–3.4] for multiple cleft lip with/without cleft palate and OR = 1.6 [95% CI = 0.7–3.4] for multiple cleft palate}. Use of pesticide products for household gardening, by mothers or by professional applicators, was associated with ORs ≥1.5 for most of the studied anomalies. Use of pesticide products for the control of pests in or around homes was not associated with elevated risks for most of the studied anomalies, although women who reported that a professional applied pesticides to their homes had increased risks for neural tube defect-affected pregnancies [OR =1.6 (95% CI = 1.1–2.5)] and limb anomalies [OR = 1.6 (95% CI = 1.0–2.7)]. Having a pet cat or dog and treating its fleas was not associated with increased anomaly risk. Women who reported living within 0.25 miles of an agricultural crop revealed increased risks for offspring with neural tube defects [OR = 1.5 (95%CI = 1.1–2.1)]. For many of the comparisons, data were sparse, resulting in imprecise effect estimation. Despite our investigating multiple sources of potential pesticide exposures, without more specific information on chemical and level of exposure, we could not adequately discriminate whether the observed effects are valid, whether biased exposure reporting contributed to the observed elevated risks, or whether nonspecific measurement of exposure was responsible for many of the observed estimated risks not being elevated. (Epidemiology 1999;10:60–66)

ISSN:1044-3983    

出版商:OVID    

年代:1999

数据来源: OVID

摘要:

Estimation of sensitivity and specificity for diagnostic or screening tests usually requires independent confirmation of subjects as diseased or nondiseased using a gold standard. In practice, however, application of the confirmatory procedure is usually limited to individuals with one or more positive test results. For situations in which two initial tests are applied, recent literature has shown that one can use the data from confirmed disease cases to estimate the ratio of test sensitivities and the information from confirmed noncases to estimate the ratio of false-positive rates. In this paper, I show that estimates of sensitivity and specificity can be obtained for each test separately, together with an estimate of the disease prevalence. The only additional information required compared with previous methodology is the total number of individuals tested, a quantity that is usually readily available. The assumption that the test errors are independent is required. Although specific patterns of test errors cannot be identified, the overall assumption can be tested using goodness of fit. I illustrate the methods using data on breast cancer screening. Provision of sensitivity and specificity estimates for each test separately provide considerably greater insight into the data than previous methods. (Epidemiology 1999; 10:67–72)

ISSN:1044-3983    

出版商:OVID    

年代:1999

数据来源: OVID

摘要:

We examined whether exercise during pregnancy is associated with chromosomally normal spontaneous abortion. We hypothesized that associations would be confined to chromosomally normal losses since only these can be influenced appreciably by experiences during pregnancy. The study population comprises women with chromosomally normal (N = 173) and aberrant (N = 173) losses. Women who exercised during pregnancy had a lower risk of a chromosomally normal spontaneous abortion (OR 0.6; 95% CI 0.3–0.9). Other types of physical activity had little effect. (Epidemiology 1999;10:73–75)

ISSN:1044-3983    

出版商:OVID    

年代:1999

数据来源: OVID

摘要:

Identified risk factors for endometrial cancer are accepted as operating through estrogen exposure. In a recent analysis, the effect of risk factors such as body mass index (BMI) was not explained by circulating estrogen concentrations. In the present analysis, we correct for measurement error associated with obtaining only one blood sample per subject. Applying regression calibration ideas, we found that error correction of log estrone had little impact on estimates of the BMI effect, suggesting that hormone measurement error does not account for the residual importance of BMI. The biologic mechanism for the increased risk associated with BMI remains to be explained. (Epidemiology 1999;10:76–79)

ISSN:1044-3983    

出版商:OVID    

年代:1999

数据来源: OVID

摘要:

I studied the relation between a maternal history of subfertility and the risk of congenital urinary tract anomalies (CUTAs) in a case-control study. I defined subfertility as having unprotected intercourse for more than 12 months without getting pregnant at any time before the conception of the index pregnancy. A maternal history of subfertility was associated with a slightly increased risk of CUTAs (adjusted odds ratio (OR) = 1.4, 95% confidence interval (CI) 0.8–2.4). Risk was higher for mothers whose subfertility occurred at 20 years of age or younger (OR = 2.2, 95% CI 1.0–4.9). The effect of a maternal history of subfertility on the risk of CUTAs was exacerbated by maternal smoking during the index pregnancy and by an early onset of smoking history. (Epidemiology 1999; 10:80–82)

ISSN:1044-3983    

出版商:OVID    

年代:1999

数据来源: OVID

摘要:

Using data from a case-control study conducted in Group Health Cooperative (GHC) of Puget Sound, we examined the relation between the use of electric blankets or heated water beds and the risk of prostate cancer. Cases were 175 prostate cancer patients ages 40–69 years. Controls were 258 male GHC members frequency matched to cases. The odds ratio (OR) for prostate cancer associated with the use of an electric blanket or heated water bed was 1.4 (95% confidence interval (CI) 0.9–2.2). The risk, however, did not tend to be higher with increasing months per year or years of use. This study did not provide clear evidence on the hypothesized association. (Epidemiology 1999;10:83–85)

ISSN:1044-3983    

出版商:OVID    

年代:1999

数据来源: OVID

ISSN:1044-3983    

出版商:OVID    

年代:1999

数据来源: OVID

ISSN:1044-3983    

出版商:OVID    

年代:1999

数据来源: OVID

ISSN:1044-3983    

出版商:OVID    

年代:1999

数据来源: OVID

ISSN:1044-3983    

出版商:OVID    

年代:1999

数据来源: OVID