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Well organized screening programmes for cervical cancer, based on exfoliative cervical cytology, are known to be effective at reducing the incidence of invasive cervical cancer and mortality from the disease. HPV testing should not replace cervical cytology as the first-line approach in screening for cervical cancer, as HPV testing is not sufficiently reliable and some cancers are not associated with HPV infection. Even though there are many unanswered questions about the validity of HPV tests, it is timely to consider whether HPV testing might improve the management of the substantial number of women whose smears are neither clearly normal nor abnormal, but are described as atypical, suspicious or mildly dyskaryotic. The efficacy and costs of incorporating HPV testing into a cervical cancer screening programme need to be evaluated in controlled trials. 相似文献
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M Booth V Beral N Maconochie L Carpenter C Scott 《Journal of epidemiology and community health》1992,46(5):528-531
STUDY OBJECTIVE--The aim was to investigate the association between reproductive, contraceptive, and menstrual factors and risk of benign ovarian tumours. DESIGN AND SETTING--This was a case-control study carried out in six London Hospitals. An interviewer administered questionnaire was used. SUBJECTS--62 women with a benign epithelial ovarian neoplasm, 37 women with a functional ovarian cyst, and 20 women with a dermoid cyst presenting between 1983 and 1985, together with 132 controls, took part in the study. MAIN RESULTS--On average, women with a benign epithelial ovarian neoplasm were older than those with a functional ovarian cyst, who in turn were older than those with a dermoid cyst. Nulliparity and infertility were associated with an increased risk, and multiparity with a reduced risk, of benign epithelial ovarian neoplasms. Infertility and pelvic inflammatory disease were associated with increased risks of functional and dermoid cysts. Recent use of oral contraceptives was associated with a reduced risk of all three tumour types. CONCLUSIONS--The findings suggest that the aetiology of ovarian cysts and benign epithelial ovarian neoplasms may differ. The aetiology of benign and malignant epithelial ovarian neoplasms may be similar, however, since some risk factors are shared. 相似文献
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Further assessment of the effects of occupational radiation exposure in the United Kingdom Atomic Energy Authority mortality study 总被引:1,自引:0,他引:1
H Inskip V Beral P Fraser M Booth D Coleman A Brown 《British journal of industrial medicine》1987,44(3):149-160
The United Kingdom Atomic Energy Authority mortality study was designed to investigate the relation between exposure to ionising radiation and mortality among the authority's employees. The present paper describes some of the problems encountered in assessing occupational exposure to low dose radiation and examines whether the study's conclusions about the relation between exposure and mortality could be affected by the methods used. The study covered the years 1946 to 1979 during which time the frequency with which personal film dosimeters were issued changed from weekly to monthly, and the threshold level below which measurements were not made decreased 20-fold. Exposure from "below threshold" readings made an important contribution to total exposure in the early years. Estimates, based on the remeasurement of a sample of old films, indicated that the average whole body exposure before 1961 may have been about double that which was measured. Furthermore, although records were kept of when dosimeters were lost or damaged, the associated exposures were unknown and could only be estimated. Workers whose dosimeter readings were missing for more than 5% of the time during which they were monitored had higher all cause mortality (p = 0.04) and higher mortality from accidents and violence (p = 0.05) than other radiation workers. The results of analyses of mortality in relation to whole body exposure were compared when the exposures included estimates of the below threshold and missing exposures and when these exposures were assumed to be zero. Some of the findings differed, but none changed sufficiently to alter the general conclusions. Although the trend in mortality from all cancers changed from one in which the increase with exposure was far from statistically significant (p = 0.3) when the below threshold and missing values were assumed to be zero to one that approached significance (p = 0.06) after they were estimated, calculations of the annual excess deaths from cancer per unit dose resulted in broadly similar estimates. Studies of workers exposed to ionising radiation usually focus on mortality in relation to whole body exposure. In the present paper its relation to neutron and surface exposure is also examined. Workers with measured neutron exposures had significantly lower all cause mortality than other workers with a radiation record (p = 0.03). Surface exposure was significantly related to mortality from all cancers (p = 0.02) and prostatic cancer (p less than 0.001). Some data on cancer registration are presented but these cannot be readily interpreted because cancer registration details were available only for ex-employees who may not be typical of the workforce as a whole. 相似文献
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Nuclear industry family study:methods and description of a United Kingdom study linking occupational information held by employers to reproduction and child health
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Maconochie N Doyle P Roman E Davies G Smith PG Beral V 《Occupational and environmental medicine》1999,56(12):798-808
OBJECTION: To describe the methods used in the nuclear industry family study for which a comprehensive database has been assembled that links employment in the nuclear industry and dosimetry records to information on employees'' reproductive health and the health of their children. To discuss the response rates and characteristics of the study population. METHODS: Occupational cohort design leading to a retrospective cohort study of reproductive outcomes reported by 46 396 current and former employees of both sexes in the nuclear industry. Employees of nuclear establishments in the United Kingdom operated by the Atomic Energy Authority, the Atomic Weapons Establishment, and British Nuclear Fuels were surveyed with postal questionnaires ot collect information on pregnancies, children,and periods of infertility. Information on employment and monitoring for ionising radiation was supplied by the employing nuclear authority and was linked to pregnancies and periods of infertility with unique personal identification numbers. RESULTS: The design and completion of this study resulted in high quality data on a representative population of the Atomic Energy Authority, Atomic Weapons Establishment, and British Nuclear Fuels workforces. The response to the survey was extremely good (82% for male workers and 88% for female workers, excluding undelivered questionnaires), and a unique relational database has been created which will enable infertility, pregnancy, and child health outcomes to be examined with respect to the employment and radiation monitoring characteristics of parents. CONCLUSION: This is the first United Kingdom study to link detailed reproductive history data to occupational information held by employers. The methods developed for the study were found to be feasible and successful. The design can be adapted for other investigations of reproductive hazards to men and women in the workplace and is currently in use to survey over 100 000 armed forces personnel in an investigation of reproductive outcome among veterans of the Gulf war. 相似文献
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Beral V Banks E Reeves G Appleby P 《Journal of epidemiology and biostatistics》1999,4(3):191-210; discussion 210-5
At least 20 million women in developed countries are estimated to be currently using hormone replacement therapy (HRT). Almost 100 epidemiological studies have reported on the relationship between the use of HRT and the risk of cancer of female reproductive organs, namely the breast, uterus or ovary. Cancer at these sites is common and there are a priori reasons why the use of hormonal therapy to 'replace' the endogenous production of ovarian hormones after the menopause might increase the risk of these cancers. The available evidence indicates that the risk of breast cancer or endometrial cancer is increased while women are using HRT, the risk increasing with increasing duration of use. Most of the evidence about these cancers relates to use of HRT preparations containing oestrogens alone. The limited evidence about combination therapy, with oestrogens and progestogens, suggests that, compared to oestrogens alone, the effect on the breast is similar, but the effect on the endometrium is diminished, the diminution in risk being greater the more days each month that progestogens are used. The effect of HRT on breast cancer wears off after use ceases and has disappeared largely, if not wholly, within 5 years, whereas the effects on endometrial cancer take longer to wear off, if at all. The breast and endometrial cancers that are diagnosed in HRT users are less aggressive clinically than cancers in never-users but, as yet, there is little reliable information about the relationship between use of HRT and mortality from these cancers. For other cancer sites, the existing data about the effects of HRT are inconclusive. The longer the period of use of HRT, the greater the excess incidence of cancer of the breast and endometrium is likely to be. Use of HRT for short periods of time should have little effect on the incidence of these cancers. The cumulative excess incidence in 1000 women who used HRT for 10 years, beginning at age 50, is estimated to be six for breast cancer, 42 for endometrial cancer in women with an intact uterus using oestrogen therapy alone and about 20 for endometrial cancer in women with an intact uterus using oestrogen-progestogen combinations. The estimate for combined therapy is based on small numbers and may well vary with the type of preparation used. The overall balance between the excess incidence of these cancers and other effects of HRT needs to be evaluated carefully and will require more reliable data than exist at present. 相似文献
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Emily Banks Gillian Reeves Valerie Beral Diana Bull Barbara Crossley Moya Simmonds Elizabeth Hilton Stephen Bailey Nigel Barrett Peter Briers Ruth English Alan Jackson Elizabeth Kutt Janet Lavelle Linda Rockall Matthew G Wallis Mary Wilson Julietta Patnick 《British medical journal》2004,328(7451):1291-1292
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