A tiered approach to prioritizing registered pesticides for potential cancer hazard evaluations: implications for decision making.

Background: Over 800 pesticides are registered for use in the United States. Human studies indicate concern that some pesticides currently in use in large quantities may also pose a carcinogenic hazard. Our objective is to identify candidates for future hazard evaluations among pesticides used in high volumes in the United States and also classified as potential carcinogens by U.

Challenges and recommendations on the conduct of systematic reviews of observational epidemiologic studies in environmental and occupational health.

Systematic reviews are powerful tools for drawing causal inference for evidence-based decision-making. Published systematic reviews and meta-analyses of environmental and occupational epidemiology studies have increased dramatically in recent years; however, the quality and utility of published reviews are variable. Most methodologies were adapted from clinical epidemiology and have not been adequately modified to evaluate and integrate evidence from observational epidemiology studies assessing environmental and occupational hazards, especially in evaluating the quality of exposure assessments.

Software Tools to Facilitate Systematic Review Used for Cancer Hazard Identification.

Objective and systematic methods to search, review, and synthesize published studies are a fundamental aspect of carcinogen hazard classification. Systematic review is a historical strength of the International Agency for Research on Cancer (IARC) Monographs Program and the United States National Toxicology Program (NTP) Office of the Report on Carcinogens (RoC). Both organizations are tasked with evaluating peer-reviewed, published evidence to determine whether specific substances, exposure scenarios, or mixtures pose a cancer hazard to humans.

Health consequences of electric lighting practices in the modern world: A report on the National Toxicology Program's workshop on shift work at night, artificial light at night, and circadian disruption.

The invention of electric light has facilitated a society in which people work, sleep, eat, and play at all hours of the 24-hour day. Although electric light clearly has benefited humankind, exposures to electric light, especially light at night (LAN), may disrupt sleep and biological processes controlled by endogenous circadian clocks, potentially resulting in adverse health outcomes. Many of the studies evaluating adverse health effects have been conducted among night- and rotating-shift workers, because this scenario gives rise to significant exposure to LAN.

How credible are the study results? Evaluating and applying internal validity tools to literature-based assessments of environmental health hazards.

Environmental health hazard assessments are routinely relied upon for public health decision-making. The evidence base used in these assessments is typically developed from a collection of diverse sources of information of varying quality. It is critical that literature-based evaluations consider the credibility of individual studies used to reach conclusions through consistent, transparent and accepted methods.

Notifiable disease reporting among public sector physicians in Nigeria: a cross-sectional survey to evaluate possible barriers and identify best sources of information.

Background: Since 2001, Nigeria has collected information on epidemic-prone and other diseases of public health importance through the Integrated Disease Surveillance and Response system (IDSR). Currently 23 diseases are designated as "notifiable" through IDSR, including human infection with avian influenza (AI). Following an outbreak of highly pathogenic avian influenza A(H5N1) in Nigerian poultry populations in 2006 and one laboratory confirmed human infection in 2007, a study was carried out to describe knowledge, perceptions, and practices related to infectious disease reporting through the IDSR system, physicians' preferred sources of heath information, and knowledge of AI infection in humans among public sector physicians in Nigeria.

Polychlorinated biphenyl (PCB) exposure in mothers and time to pregnancy in daughters.

Developmental exposure to polychlorinated biphenyls (PCBs) disrupts reproduction in animals. Human data are lacking. We measured PCBs in preserved mothers' serum samples collected during 1960-1963, 1-3 days after their daughters' birth.

Prostate cancer and vasectomy: a hospital-based case-control study in China, Nepal and the Republic of Korea.

Background: The study of a possible relationship between vasectomy and prostate cancer has yielded mixed results. Data from developing countries are limited.

Study Design: We conducted a hospital-based case-control study in China, Nepal and the Republic of Korea to evaluate the risk of prostate cancer after vasectomy.

Depo medroxyprogesterone acetate (DMPA) and combined oral contraceptives and cervical carcinoma in-situ in women aged 50 years and under.

Most low-resource settings depend on hormonal contraceptives for their family planning programmes and cervical cancer occurs in higher frequency in these populations. To determine whether hormonal contraception use increases cervical carcinoma in-situ (CIS) risk, a case-control study was conducted in the Kingston and St Andrew Corporate area of Jamaica, using 119 cases from the Jamaica Tumour Registry and 304 population controls matched on year of Papanicolaou (Pap) smear and clinic where Pap smear was obtained. While CIS cases were more likely to have 'ever used' combined oral contraceptives (COC) (OR = 1.

DDT and DDE exposure in mothers and time to pregnancy in daughters.

Reproductive-tract anomalies after administration of the potent oestrogen, diethylstilboestrol, in pregnant women raised concerns about the reproductive effects of exposure to weakly oestrogenic environmental contaminants such as bis[4-chlorophenyl]-1,1,1-trichloroethane (p,p'-DDT) or its metabolites, such as bis[4-chlorophenyl]-1,1-dichloroethene (p,p'-DDE). We measured p,p'-DDT and p,p'-DDE in preserved maternal serum samples drawn 1-3 days after delivery between 1960 and 1963. We recorded time to pregnancy in 289 eldest daughters 28-31 years later.

New contraceptive eligibility checklists for provision of combined oral contraceptives and depot-medroxyprogesterone acetate in community-based programmes.

Community-based services (CBS) have long used checklists to determine eligibility for contraceptive method use, in particular for combined oral contraceptives (COCs) and the 3-month injectable contraceptive depot-medroxyprogesterone acetate (DMPA). As safety information changes, however, checklists can quickly become outdated. Inconsistent checklists and eligibility criteria often cause uneven access to contraceptives.

Safety and effectiveness of vasectomy.

Objective: To recommend further research on vasectomy based on a systematic review of the effectiveness and safety of vasectomy.

Design: A systematic MEDLINE review of the literature on the safety and effectiveness of vasectomy between 1964 and 1998.

Main Outcome Measure(s): Early failure rates are <1%; however, effectiveness and complications vary with experience of surgeons and surgical technique.

Early onset baldness and prostate cancer risk.

Prostatic carcinoma is the leading cancer among American men, yet few risk factors have been established. Although increased androgen levels have long been associated with both prostatic carcinoma and baldness, to date no studies have shown an association between hair patterning and prostate cancer risk. A lack of standardized instruments to assess baldness or the assessment of hair patterning during uninformative periods of time may have precluded the ability of previous studies to detect an association.

Estimates of the risk of cardiovascular death attributable to low-dose oral contraceptives in the United States.

Objective: Our purpose was to estimate the annual risk of death in the United States from cardiovascular disease attributable to low-dose combination oral contraceptives.

Study Design: Estimates of the risk of death from cardiovascular disease attributable to low-dose oral contraceptives were modeled on data from studies published through 1997 and from age-specific mortality rates in the United States for 1993 and 1994.

Results: Attributable risk of death from cardiovascular disease resulting from oral contraceptive use is 0.

Modeled estimates of myocardial infarction and venous thromboembolic disease in users of second and third generation oral contraceptives.

Consistent reports from several recent studies suggest that users of third generation oral contraceptives (OCs) containing gestodene and desogestrel may be at increased risk of venous thromboembolic disease (VTE). Paradoxically, other reports indicate that these users may be at decreased risk of acute myocardial infarction (MI) compared with users of second generation OCs. To determine whether the potentially increased risk of VTE would outweigh the potentially reduced risk of MI in users of third generation OCs, we conducted an analysis to quantify the trade-offs providers and users may be faced to make between these formulations.

Epithelial ovarian cancer risk among women with polycystic ovary syndrome.

Objective: To investigate the relationship between polycystic ovary syndrome (PCOS) and ovarian cancer, and to present three hypotheses regarding hormonal factors and the risk of ovarian cancer in women.

Methods: Data were analyzed from a population-based, case-control study, the Cancer and Steroid Hormone Study, to test the hypotheses. Four hundred seventy-six subjects with histologically confirmed epithelial ovarian cancer were identified from eight tumor registries of the Surveillance Epidemiology and End Results program.

A medical record linkage analysis of abortion underreporting.

Inaccuracy in women's reports of their abortion histories affects many areas of interest to reproductive health professionals and researchers. The identification of characteristics that affect the accuracy of reporting is essential for the improvement of data collection methods. A comparison of the medical records of 104 American women aged 27-30 in 1990-1991 with their self-reported abortion histories revealed that 19% of these women failed to report one or more abortions.

Risk factors for menopausal hot flashes.

Objective: To find predictors of hot flashes at natural menopause.

Methods: A cross-sectional sample of 334 black and white, naturally menopausal women was selected from a control group in a population-based study of reproductive cancers in central North Carolina. Women reported whether they had experienced hot flashes at the time of menopause.

Selection bias associated with contraceptive practice in time-to-pregnancy studies.

In studies of subfertility using data on time to pregnancy (the number of noncontracepting menstrual cycles required to conceive), many pregnancies are not included in analyses because time-to-pregnancy data cannot always be collected. Birth control failures are one such group (couples who are using birth control regularly or sporadically, but become pregnant anyway). The more fecund couples are more likely to have birth control failures, and consequently, more likely to be excluded from analyses.

Breech presentation and fetal growth retardation.

Although it has been consistently demonstrated that breech presentation is associated with fetal growth retardation, this relationship has not been clarified. This study intends to elucidate this association by use of live births recorded in North Carolina in 1988 and 1989. A remarkable difference in birth weight between breech and vertex infants existed only in the preterm births.

Association of paternal alcohol use with gestational age and birth weight.

Paternal alcohol use has been associated with a number of adverse reproductive outcomes in laboratory animals and there is one epidemiologic report of a detrimental effect on infant birth weight. To expand the epidemiologic evidence, data from the Child Health and Development Studies were analyzed. Data collected from the onset of prenatal care in 10,232 women enrolled in the Kaiser Foundation Health Plan and residing in the San Francisco East Bay area between June 1959 and September 1966 were available, including information on the mother's report of paternal alcohol consumption and a number of potential confounders.

A case-control study of paternal smoking and birth defects.

Although the influence of paternal smoking on birth defects is of great public interest, epidemiological evidence concerning this potential relationship is extremely limited. A stratified random sample of 29 hospitals in the Shanghai Municipality, China, was used to select 1012 birth defects cases and controls. Mothers of the cases and controls were interviewed in the hospitals from October 1986 to September 1987.