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S Preston-Martin

Publications and source records attributed to S Preston-Martin.

At least 73 records · Page 4Linked to original sources
PubMed1996

Head injury as a risk factor for brain tumors in children: results from a multicenter case-control study.

We evaluated the risk of brain tumor occurrence in relation to previous head injury in a population-based case-control study of 540 children with a primary brain tumor and 801 control children. The risk of a brain tumor among children with a previous head injury that resulted in medical attention was slightly elevated when compared with children with no reported head injury [odds ratio (OR) = 1.4; 95% confidence limits (CL) = 1.0, 1.9]. This effect was stronger when we restricted the head-injured group to the few children with loss of consciousness (OR = 1.6; 95% CL = 0.6, 3.9) or an overnight admission to a hospital (OR = 1.7; 95% CL 0.7, 4.6), relative to those with no head injury. We observed no appreciable association between brain tumor occurrence and birth injury involving the head or a forceps delivery. Among the few children with either a birth injury or forceps delivery and a subsequent head injury, we observed approximately twofold elevations in risk. The OR was 2.6 (95% CL = 1.1, 6.9) for those with a birth injury and subsequent head injury, relative to those with neither a birth injury nor head injury. Our results provide only weak evidence in support of head injury as an etiologic agent for brain tumor occurrence in children, although most of our exposed group had only mild head injury.

Adolescent↗
PubMed1995

A case-control study of maternal risk factors for thyroid cancer in young women (California, United States).

A population-based case-control interview study investigated whether reproductive factors are related to the striking female-over-male excess of thyroid cancer among women of reproductive age in Los Angeles County, CA (United States). As a separate component of that study, mothers of 153 cases and 140 controls who were age 40 or younger at diagnosis or reference date were interviewed by telephone to determine the significance of family and maternal risk factors in the subsequent development of thyroid cancer among the daughters. More case than control mothers experienced miscarriage prior to the index pregnancy (odds ratio [OR] = 2.0, 95 percent confidence interval [CI] = 1.1-3.5). Increased risk was associated with family history of thyroid cancer or other thyroid disease (OR = 2.1, CI = 1.2-3.6). More control than case mothers smoked during the index pregnancy (OR = 0.6, CI = 0.4-1.0); however, among mothers who smoked, case mothers smoked more. Case mothers experienced a greater increase in weight from minimum adult weight to weight at index pregnancy (P for trend = 0.01). Reports from mothers also confirmed the risk associated with the daughter's exposure to ionizing radiation from birth through adolescence; ionizing radiation remains the best-established risk factor for thyroid cancer.

Adolescent↗
PubMed1995

The Utah Leukemia Case-Control Study: dosimetry methodology and results.

This paper discusses the dosimetry methodology used to estimate bone marrow dose and the results of dosimetry calculations for 6,507 subjects in an epidemiologic case-control study of leukemia among Utah residents. The estimated doses were used to determine if a higher incidence of leukemia among residents of Utah could have been attributed to exposure to radioactive fallout from above-ground nuclear weapons tests conducted at the Nevada Test Site. The objective of the dosimetry methodology was to estimate absorbed dose to active marrow specific to each case and each control subject. Data on the residence of each subject were available from records of the Church of Jesus Christ of Latter-day Saints. Deposition of fallout was determined from databases developed using historical measurements and exposure for each subject from each test was estimated using those data. Exposure was converted to dose by applying an age-dependent dose conversion factor and a factor for shielding. The median dose for all case and control subjects was 3.2 mGy. The maximum estimated mean dose for any case or control was 29 +/- 5.6 mGy (a resident of Washington County, UT). Uncertainties were estimated for each estimated dose. The results of the dosimetry calculations were applied in an epidemiological analysis.

Adolescent↗
PubMed1995

The Utah Thyroid Cohort Study: analysis of the dosimetry results.

Above ground testing of nuclear weapons at the Nevada Test Site (NTS) during the 1950s created radioactive fallout that was dispersed into the atmosphere and deposited over a large geographical area of the U.S. One area believed to have received a considerable amount of exposure to radioiodines (131I and 133I) in the fallout was southwest Utah and southeast Nevada. This paper describes the estimates of doses to the thyroid for a cohort of 3,545 subjects who were children during the atmospheric testing period. This group of children was examined for thyroid disease during 1965-1970 and again in 1985-1986. The cohort was made up of children who lived in three counties in 1965: Washington County, Utah; Lincoln County, Nevada; and Graham County, Arizona (originally thought to be an unexposed group). Pathway analysis was used in the dosimetry, considering exposures through the ingestion of milk and vegetables, inhalation of iodine during the passage of the fallout cloud, and external exposure. Specific data were obtained on diet (including sources and levels of milk and vegetables consumed, residence history, and lifestyle) by interviewing the parents or nearest living relative of subjects. The final dosimetry file for each member of the cohort contained specific doses to the thyroid glands and uncertainties (reported as geometric standard deviations, GSD) related to each dose estimate. The mean absorbed dose to the thyroid for subjects living in Washington County, Utah, was 170 mGy; for Lincoln County, Nevada, 50 mGy; and for those living in Graham County, Arizona, 13 mGy. The maximum dose to any subject was 4,610 mGy. There were 10 subjects who had doses greater than 1 Gy. The majority of uncertainty values calculated in this study were GSD values between 2.0 and 4.0. The results of the dosimetry were combined with the results of clinical examinations of the cohort to determine if a causal relationship exists between dose to thyroid from NTS generated radioactive iodines and the incidence of thyroid disease.

Adult↗
PubMed1995

Misclassification of smoking status among women in relation to exposure to environmental tobacco smoke.

In studies of the health effects of exposure to environmental tobacco smoke (ETS), misclassification of active smokers has the potential to bias the estimates of disease risk. Biochemical validation of exposure to ETS can provide objective evidence of current smoking status in epidemiological studies. Intrinsic to this effort is the establishment of appropriate cut-off points for the measurements of tobacco biomarkers. Within a collaborative study on ETS co-ordinated by the International Agency for Research on Cancer, questionnaire data and urine samples were collected from 1,369 women at 13 centres in 10 countries. Forty seven of these women had urine cotinine levels above 50 ng.mg-1 creatinine, a level used to discriminate smokers from nonsmokers in previous studies. The distributions of the subjects across cotinine values and self-reported exposure to ETS was consistent with the association, at one extreme, of moderate cotinine levels (50-150 ng.mg-1) with very high exposure to ETS, and, at the other extreme, of very high cotinine levels indicating actual use of nicotine-containing products in women with low ETS exposure. Using the cut-off point of 150 ng.mg-1, only 1.5% of the alleged nonsmokers were reclassified as current light smokers. Potential bias due to smoker misclassification is very unlikely to be responsible for the increased health risks observed in epidemiological studies on ETS.

Bias↗
PubMed1995

Spinal meningiomas in women in Los Angeles County: investigation of an etiological hypothesis.

A series of 3 studies explored the hypothesis that the preponderance of spinal meningiomas among postmenopausal women relates to their higher prevalence of spinal osteoporosis: (a) medical records showed that meningiomas in women, unlike other spinal tumors, usually arise in the mid thoracic spine where osteoporotic vertebral fractures predominate; (b) radiographic evidence of osteoporosis was seen commonly with meningiomas but not with other spinal tumors; and (c) age-adjusted multivariate analysis of data from an interview study of 81 women with spinal meningioma and 155 random digit dial controls showed 6 factors related to risk. Four factors were protective: (a) current use (at diagnosis) of estrogen replacement therapy [odds ratio (OR) = 0.2; 95% confidence interval (CI) = 0.1-0.6]; (b) past use of oral contraceptives (P trend < 0.01); (c) past participation in sports (OR = 0.5; CI = 0.2-0.9); and (d) premenopausal status (OR = 0.2; CI = 0.1-0.7). Risk increased among women who had ever smoked cigarettes (OR = 1.7; CI = 0.9-3.1) or had a history of high dose radiography (> 500 mrad exposure to active marrow/examination; includes upper or lower gastrointestinal series and/or cardiac angiography; OR = 2.9, and CI = 1.6-5.3), although no association was seen with prior radiotherapy. Other results that did not support the hypothesis include findings that cases and controls were similar in mean body weight and in the proportion who had postmenopausal fractures or height loss. In conclusion, these studies lend some support to our hypothesis, but other known meningioma risk factors such as ionizing radiation also appear important.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1995

Do the nonsmoking daughters of smokers tend to marry smokers? Implications for epidemiological research on environmental tobacco smoke: the IARC collaborative study.

The IARC collaborative study on exposure to environmental tobacco smoke (ETS) involved collecting interview data and biochemical indicators of exposure from 1369 nonsmoking women in 13 centers in 10 countries. Information on childhood and adulthood exposure to other people's smoke and duration of this exposure from both parents and spouse was gathered at the interview. Of the 900 women whose husbands smoked (current or exsmokers), 71.3% had one or both parents who smoked (predominantly the father), whereas among the 277 women married to never-smokers, only 60.3% had at least one parent who smoked. The odds ratio for the daughter of a smoker to marry a smoker was, therefore, 1.64 (95% confidence interval = 1.24-2.17; P > 0.001), and there was an exposure-response relation between the number of years of childhood exposure to ETS from the parents and the likelihood of being married to a smoker. These results show that nonsmoking women married to smokers are more likely to have been exposed to tobacco pollution during their whole life. Because the duration of exposure is known to be important in the genesis of lung cancer, some of the excess risk of lung cancer in nonsmoking women married to smokers may be due exposure to ETS from parents during childhood.

Adolescent↗
PubMed1994

Dietary glutathione intake and the risk of oral and pharyngeal cancer.

Glutathione, a tripeptide found in a variety of foods, may function as an anticarcinogen by acting as an antioxidant and by binding with cellular mutagens. The association between dietary glutathione intake and risk of oral and pharyngeal cancer was investigated using data from 1,830 white participants (855 cases and 975 controls) in a population-based case-control study conducted in New Jersey; metropolitan Atlanta, Georgia; Los Angeles County, California; and Santa Clara and San Mateo counties, south of San Francisco-Oakland, California, during 1984-1985. The estimated relative risk of cancer among people with the highest quartile of glutathione intake from all sources was 0.5 (95% confidence interval 0.3-0.7). When analyzed by dietary source, however, glutathione intakes derived from all vegetables and from meat were not related to risk of cancer. Only glutathione derived from fruit and from vegetables commonly consumed raw was associated with reduced oral cancer risk. Relative to the lowest level of combined intake of fruit and of fruit-derived glutathione, risk of cancer decreased slightly with increasing intake of fruit glutathione. This analysis was limited, however, by the small numbers of subjects with extreme combinations of intakes. Further studies are needed to distinguish the potential effect of glutathione from that of fruit and raw vegetables per se or from the influence of other constituents in these foods.

Adult↗
PubMed1994

Second cancers following oral and pharyngeal cancers: role of tobacco and alcohol.

BACKGROUND: The exceptionally high rate of second primary cancers among patients with oral and pharyngeal cancers is well recognized, yet there has been limited epidemiologic study of risk factors for second tumors. PURPOSE: To evaluate the relation of smoking and alcohol consumption to the development of second cancers among this high-risk patient group, we conducted a nested case-control study. METHODS: A total of 1090 patients enrolled in a 1984-1985 population-based, case-control study of oral cancer in four areas of the United States were followed through June 1989 for the occurrence of second primary cancers. Information on tobacco and alcohol consumption was obtained from the original interviews and was updated by follow-up interviews obtained for 80 case patients with second cancers and 189 sex-, study area-, and survival-matched cancer patients free of second cancers (control subjects). RESULTS: Tobacco smoking and alcohol drinking each contributed to risk of second cancers, with the effects of smoking more pronounced than those of alcohol. The odds ratios (ORs) for smoking (adjusted for alcohol) rose with duration and intensity of smoking and were strongest for tumors of the aerodigestive tract (oral cavity, pharynx, esophagus, larynx, and lungs), with ORs reaching 4.7 (95% confidence interval [CI] = 1.4-16) among smokers of 40 or more cigarettes per day for 20 or more years. Current smokers as of the baseline survey experienced a fourfold increased risk of a second aerodigestive tract cancer relative to nonsmokers and former smokers. No reduction in risk was associated with cessation of smoking or drinking at or after the index diagnosis, although the short median interval (27 months) between tumor diagnoses limited observation of the effects due to recent cessation. Risk was significantly reduced, however, 5 years after smoking cessation. Among drinkers, second cancer risk was greatest for beer intake, with an OR for a second aerodigestive tract cancer of 3.8 (95% CI = 1.2-12) for 15 or more beers per week. CONCLUSIONS: Oral and pharyngeal cancer patients with the highest intakes of tobacco and alcohol are the ones most prone to develop second primary cancers. IMPLICATIONS: Avoidance of tobacco smoking and alcohol drinking is the most desirable way not only to prevent primary oral cancers, but also to reduce risk of second cancers of the aerodigestive system.

Aged↗
PubMed1994

Processed meats and risk of childhood leukemia (California, USA).

The relation between the intake of certain food items thought to be precursors or inhibitors of N-nitroso compounds (NOC) and risk of leukemia was investigated in a case-control study among children from birth to age 10 years in Los Angeles County, California (United States). Cases were ascertained through a population-based tumor registry from 1980 to 1987. Controls were drawn from friends and by random-digit dialing. Interviews were obtained from 232 cases and 232 controls. Food items of principal interest were: breakfast meats (bacon, sausage, ham); luncheon meats (salami, pastrami, lunch meat, corned beef, bologna); hot dogs; oranges and orange juice; and grapefruit and grapefruit juice. We also asked about intake of apples and apple juice, regular and charcoal broiled meats, milk, coffee, and coke or cola drinks. Usual consumption frequencies were determined for both parents and the child. When the risks were adjusted for each other and other risk factors, the only persistent significant associations were for children's intake of hot dogs (odds ratio [OR] = 9.5, 95 percent confidence interval [CI] = 1.6-57.6 for 12 or more hot dogs per month, trend P = 0.01), and fathers' intake of hot dogs (OR = 11.0, CI = 1.2-98.7 for highest intake category, trend P = 0.01). There was no evidence that fruit intake provided protection. While these results are compatible with the experimental animal literature and the hypothesis that human NOC intake is associated with leukemia risk, given potential biases in the data, further study of this hypothesis with more focused and comprehensive epidemiologic studies is warranted.

Animals↗
PubMed1994

Second cancers following oral and pharyngeal cancer: patients' characteristics and survival patterns.

A survey was made of second primary cancers among patients who were enrolled in a large case-control investigation of oral and pharyngeal cancer, hereafter called oral cancer, during 1984-1985 in four areas of the United States. Among the original 1090 patients with oral cancer (nearly all squamous cell carcinomas), 107 developed a second cancer (one-half of them squamous cell) by the end of follow-up in June 1989 (average follow-up 2.6 years), with 69% occurring in the oral cavity, pharynx, oesophagus, larynx or lung. Rates of second tumours varied by age and socioeconomic status, but not sex or race, and were higher among those whose initial cancer was localised, even after adjusting for their longer survival. Long-term survival was lower among those with second cancers. Conditional on surviving for 2 years, the survival at 5 years was under 50% and nearly 70%, respectively, for those with versus those without a second cancer in the first 2 years. These findings confirm the exceptionally high rate of second cancers (especially of the aerodigestive tract) following oral cancer, describe the clinical and pathological features of patients with multiple cancers and indicate the importance of preventive measures.

Adenocarcinoma↗
PubMed1994

Familial risk in oral and pharyngeal cancer.

We examined the relationship between a family history of cancer and risk of oral and pharyngeal cancer using epidemiological data from a large case-control investigation of these tumours. 487 (45.7%) of the cases and 485 (41.0%) of the controls reported cancer in a parent or a sibling. After controlling for age, race, sex, study location, respondent status and smoking and alcohol use, the OR associated with any cancer in the family was 1.1 [95% confidence interval (CI) 0.9-1.3]. Risks were non-significantly elevated among those with a history of cancers arising from the oral cavity/pharynx (OR = 1.2, 95% CI 0.7-2.3), oesophagus/larynx (OR = 1.6, 95% CI 0.7-3.8) and lung (OR = 1.2, 95% CI 0.8-1.8), with the excess risk primarily among those for whom a male relative, particularly a brother, was affected with these smoking-related cancers. In addition, an elevated risk of oral/pharynx cancer was found among those whose sisters developed other cancers (OR = 1.6, 95% CI 1.1-2.2). Subsite analyses revealed stronger elevated risks of smoking-related cancers in relatives of pharyngeal cancer cases (OR = 1.7, 95% CI 1.1-2.8) than of oral cancer patients. The data indicate that there is at most a weak familial aggregation of oral/pharynx cancers. Furthermore, since the excess familial risk of oral/pharynx cancer was associated with smoking-related cancers among male but not female relatives, it seems likely that environmental factors (notably smoking and drinking) contribute to the familial tendency observed in this study.(ABSTRACT TRUNCATED AT 250 WORDS)

Case-Control Studies↗
PubMed1994

Dietary factors and second primary cancers: a follow-up of oral and pharyngeal cancer patients.

To investigate the possible relationship between dietary factors and the development of multiple primary cancer, a nested case-control study was carried out within a cohort of 1,090 oral and pharyngeal cancer patients. This patient group, enrolled in 1984-1985 in a population-based case-control study conducted in four areas of the United States, was followed up through June 1989 for the occurrence of second primary cancer. Information on a number of risk factors, including diet, ascertained from interviews conducted at baseline (1984-1985) and at follow-up were compared between 80 patients with histologically confirmed second primary cancers (39% in the upper aerodigestive tract, 32% in the lung, 29% elsewhere) and 189 sex- and survival-matched control patients free of second cancers. Although few significant trends emerged, the results were suggestive of a protective effect provided by higher intake of vegetables. Risk of second primary cancers was 40-60% lower among those with the highest levels of intake for total vegetables and most vegetable subgroups, including dark yellow, cruciferous, and green leafy vegetables and legumes. Risks were also nonsignificantly lower among those with high consumption of vitamin C and carotenoids, with the adverse effects of alcohol being most evident among heavy drinkers with low vitamin C or carotenoid intake. There was also some evidence of an interaction between smoking and vitamin C consumption, but numbers of nonsmokers were small. Among other dietary factors considered, positive associations were found with increasing consumption of meats, liver, and retinol. The findings suggest that dietary factors contribute along with alcohol and smoking to the excess risks of second primary cancers among patients with oral and pharyngeal cancers.

Aged↗
PubMed1993

A cohort study of thyroid disease in relation to fallout from nuclear weapons testing.

OBJECTIVE: To estimate individual radiation doses and current thyroid disease status for a previously identified cohort of 4818 schoolchildren potentially exposed to fallout from detonations of nuclear devices at the Nevada Test Site between 1951 and 1958. DESIGN: Cohort analytic study. SETTING: Communities in southwestern Utah, southeastern Nevada, and southeastern Arizona. PARTICIPANTS: Individuals who were still residing in the three-state area (n = 3122) were reexamined in 1985 and 1986, and information on the subjects' and their mothers' milk and vegetable consumption during the fallout period was obtained by telephone interview (n = 3545). After exclusions to eliminate missing data and confounding factors, 2473 subjects were available for analysis. MAIN OUTCOME MEASURES: Individual radiation doses to the thyroid were estimated by combining consumption data with radionuclide deposition rates provided by the US Department of Energy and a survey of milk producers. Relative risk models adjusted for age, sex, and state were fitted using maximum likelihood to period prevalence data for thyroid carcinomas, neoplasms, and nodules. RESULTS: Doses ranged from 0 mGy to 4600 mGy, and averaged 170 mGy in Utah. There was a statistically significant excess of thyroid neoplasms (benign and malignant; n = 19), with an increase in excess relative risk of 0.7% per milligray. A relative risk for thyroid neoplasms of 3.4 was observed among 169 subjects exposed to doses greater than 400 mGy. Positive but nonsignificant dose-response slopes were found for carcinomas and nodules. CONCLUSIONS: Exposure to Nevada Test Site-generated radioiodines was associated with an excess of thyroid neoplasms. The conclusions are limited by the small number of exposed individuals and the low incidence of thyroid neoplasms.

Adolescent↗
PubMed1993

Racial differences in risk of oral and pharyngeal cancer: alcohol, tobacco, and other determinants.

BACKGROUND: In the United States, Blacks have increasingly higher rates of oral and pharyngeal cancer (oral cancer) than Whites, but determinants of the racial disparity have not been clear. PURPOSE: The purpose of this study was to explore reasons for the higher incidence of oral cancer among Blacks than Whites. METHODS: We used data from a large, population-based case-control study of oral cancer risk factors conducted in four areas of the United States. On the basis of interviews that ascertained characteristics of 1065 oral cancer patients (871 Whites and 194 Blacks) and 1182 controls (979 Whites and 203 Blacks), we examined racial differences in exposure prevalences and relative risks for a number of known etiologic factors, including tobacco and alcohol consumption, diet, and socioeconomic and other variables. To evaluate the extent to which the major risk factors explained the excess risk of oral cancer among Blacks, population-attributable risks were calculated. RESULTS: Differences with respect to alcohol consumption, especially among current smokers, emerged as the most important explanatory variables. After adjusting for smoking, heavy drinking (> or = 30 drinks/week) resulted in a 17-fold increased risk among Blacks and a ninefold increase among Whites. Among drinkers, Blacks tended to drink more than Whites. Also, a higher (P = .01) percentage of Blacks (37%) than Whites (28%) were current smokers, although there were little or no racial differences in relative risks or patterns of use for other smoking variables, including number of cigarettes smoked per day, years of smoking, and age started smoking. From population-attributable risk calculations, we estimated that differences in alcohol and tobacco use account for the bulk of the higher incidence of oral cancer among Blacks in the United States and that, in the absence of alcohol and tobacco, the rates of this cancer according to race (Black, White) and gender would be nearly equal. With regard to other potential etiologic factors, protective effects provided by higher dietary intake of fruits and vitamin C were more pronounced for Whites, while Blacks more often tended to be in sociodemographic and medical or dental health categories associated with increased risk. CONCLUSIONS: These analyses provide evidence that various environmental or lifestyle determinants of oral cancer may contribute to the higher oral cancer rates in Blacks than in Whites in the United States, but that patterns and risks associated with alcohol consumption, particularly among current smokers, are the most important contributors to the excess risk in Blacks. IMPLICATIONS: These findings suggest that the key to prevention of oral and pharyngeal cancers among both Blacks and Whites is reduced intake of alcoholic beverages and, because of strong interactive effects, the cessation of smoking.

Adult↗
PubMed1993

A case-control study of thyroid cancer in women under age 55 in Shanghai (People's Republic of China).

A population-based interview study of 207 case-control pairs investigated reproductive, dietary, and other factors thought likely to increase thyroid cancer risk among women of reproductive age in Shanghai. Of particular interest were factors that might help explain the striking female over male excess in this age group. Risk was strongly associated with prior goiter or benign nodules (odds ratio [OR] = 7.0, 95 percent confidence interval [CI] = 2.5-27.5) and miscarriage as outcome of first pregnancy (OR = 9.9, CI = 2.0-48.4). Weaker associations were seen for women who were ever-pregnant (OR = 2.1, CI = 1.1-4.2), ever had an induced abortion (OR = 1.6, CI = 0.9-2.9), and ever used oral contraceptives (OR = 1.7, CI = 1.0-3.1). Compared with controls, cases gained significantly more weight from menarche to highest nonpregnant weight (P trend < 0.01). Overall, cases ate more fish and shellfish, but there was no trend with level of consumption. More cases had a parent, sibling, or child with thyroid disease (OR = 5.2, CI = 2.5-12.1). Our findings relating to goiter and benign nodules and various reproductive factors support earlier studies. Consumption of seafood was difficult to evaluate; more detailed dietary data are needed to assess iodine intake.

Abortion, Spontaneous↗
PubMed1993

Descriptive epidemiology of primary cancer of the brain, cranial nerves, and cranial meninges in New Zealand, 1948-88.

We used New Zealand data on occurrence of different types of brain cancer to investigate: (i) a possible secular increase which has been seen worldwide and has generated considerable debate; (ii) possibly higher rates among Maori; and (iii) possibly higher risks related to social class and occupation. Data from the NZ Cancer Registry on the 5,684 brain cancers diagnosed among NZ residents from 1948-88 were used to study the pattern of occurrence by gender, age, race, calendar year, social class, occupation, and histology. Age-standardized brain-cancer incidence rates per 100,000 more than doubled over the 41-year period (from 2.9 to 6.9 in males and from 2.1 to 5.1 in females). A strong trend of increasing incidence with increasing social class is seen in males (Ptrend = 0.01). Among Maori, the proportion of all brain cancer that is medulloblastoma is four times that among non-Maori, and the proportion of all brain cancers that lack histologic confirmation is about 40 percent higher. Elevated risks are seen among: dairy farmers (odds ratio [OR] = 3.4, 95 percent confidence interval [CI] = 1.9-6.0); sheep handlers (OR = 2.7, CI = 1.4-5.3); livestock workers (OR = 3.8, CI = 1.7-8.4); and farm managers (OR = 3.2, CI = 1.4-7.2); as well as among electrical engineers (OR = 8.2, CI = 20-34.7); electricians (OR = 4.6, CI = 1.7-12.2); and other electrical workers. Brain cancer rates in NZ have increased steadily since 1948, but this increase has leveled off in the most recent five-year period. Although brain cancer rates are likely to be underestimated among the Maori, an excess of medulloblastoma is evident in this group.

Adolescent↗