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1.
E. A. Clarke  S. Hilditch 《CMAJ》1983,129(12):1271-1273
Since cancer registries have different recording practices, the incidence rates that they report must be compared with caution. Indexes of reliability of recording indicated that in 1971 the reported incidence of cervical cancer in Ontario was too high. In 1971 Ontario used a method of passive reporting of cancer cases: the Ontario Cancer Registry linked hospital reports, death certificates and reports from the Ontario Cancer Treatment and Research Foundation''s treatment centres to produce a single record for each case. Pathological confirmation was requested for cases thus recorded by the registry. In 26% of cases a diagnosis other than cervical cancer was indicated. With these cases omitted, the incidence rate became 15.1/100 000, as opposed to the 20.5/100 000 reported by the registry.  相似文献   

2.
The Ontario Laboratory Proficiency Testing Program's testing model and the results of early surveys of cytology laboratories have been previously described. To test consistency and accuracy, the same slides from one survey were recirculated to the same laboratory in the next survey. There was no statistical difference in either the accuracy or consistency in reporting by the various categories of personnel. Analysis of the data by category of diagnosis showed the reporting of "no abnormal cells" and "benign atypia" to be slightly more accurate and "moderate dysplasia" and "severe dysplasia" to be slightly less accurate than the reporting in other categories. Consistency in reporting appeared to be slightly less accurate in severe dysplasia than in the other categories. The analysis, which includes the results from all licensed cytology laboratories in Ontario, provides evidence that, in the reporting of cervical cytologic material, it is feasible to differentiate among the various categories within the spectrum of squamous epithelial abnormalities with a general level of accuracy and consistency that, although satisfactory, is not yet ideal.  相似文献   

3.
Surgical reduction of the female breast (reduction mammaplasty) is very common in plastic surgery. The purpose of this study was to determine whether women who have undergone breast reduction surgery are at the same, greater, or lesser risk of developing breast cancer than women who have not undergone breast reduction surgery. This study incorporates a population-based, non-concurrent cohort linkage methodology. The Canadian Institute for Health Information hospital records were used to identify all Ontario women who had undergone breast reduction surgery in Ontario between 1979 and 1992. Three computerized probabilistic record linkages were performed. The first linkage was between a file of the 28,042 Ontario women who had undergone bilateral breast reduction surgery between April 1, 1979, and December 31, 1992, and a file of incident cancer cases among Ontario women for the calendar period 1979 to 1993. Follow-up of the cohort was undertaken starting from the date of breast reduction surgery, and vital status was ascertained as of December 31, 1993, by record linkage with the Ontario Mortality Database maintained at the Ontario Cancer Registry. The incidence of cancer in the Ontario breast reduction cohort was compared with the cancer incidence of the general Ontario population after appropriate adjustments for age and calendar time period. The expected number of cancers was calculated using the "PERSON YEARS" computer program. Within the cohort, followed for an average of 6.5 years after bilateral breast reduction surgery, 101 breast cancers were observed and 165.8 were expected, for a standardized incidence ratio of 0.61 (0.50 to 0.74, 95 percent confidence interval). This effect was independent of patient age at breast reduction. This study demonstrates that there is no increased risk of breast cancer after bilateral breast reduction surgery and, in fact, a significant decreased risk existed in women followed for an average of 6.5 years.  相似文献   

4.
E M Adlaf  A Paglia  F J Ivis  A Ialomiteanu 《CMAJ》2000,162(12):1677-1680
BACKGROUND: During the 1990s, rates of nonmedical drug use among adolescents escalated. We assessed data from 5 cycles of the Ontario Student Drug Use Survey for overall trends in the proportion of students reporting illegal drug use between 1991 and 1999. METHODS: The survey is a repeated, cross-sectional, 2-stage cluster-design survey of students enrolled in grades 7, 9, 11 and 13. Outcome measures were prevalence of use of 17 drugs, including alcohol and tobacco, over the 12 months preceding the survey. RESULTS: The rates of drug use increased between 1993 and 1999. The 95% confidence intervals (CIs) for the differences in proportions between 1997 and 1999 indicated significant increases in the overall use of 6 drugs: alcohol (95% CIdiff 6.1, 1.9-10.3), cannabis (95% CIdiff 46.3, 0.2-8.4), glue (95% CIdiff 2.3, 1.3-3.3), other solvents (95% CIdiff 5.0, 3.1-6.3), barbiturates (95% CIdiff 1.9, 0.4-3.4) and hallucinogens such as mescaline and psilocybin (95% CIdiff 3.5, 0.8-6.9). Fewer grade 7 students in 1999 than in earlier cohorts reported using alcohol or cigarettes by age 9. INTERPRETATION: The public health implications of the findings are mixed. On the positive side, there is no evidence of increases in early onset of drug use. On the negative side, the overall proportion of students reporting illegal drug use has continued to rise.  相似文献   

5.
H K Weir  L D Marrett  V Moravan 《CMAJ》1999,160(2):201-205
BACKGROUND: Testicular cancer is rare but is notable because it affects mainly young men. The incidence of this disease has been increasing in developed countries throughout the world for several decades. The authors examined trends in the incidence of testicular germ cell cancer in Ontario for the period 1964-1996 according to the 2 main histologic groups, seminoma and non-seminoma. METHODS: Data on incident cases of testicular germ cell cancer diagnosed in Ontario residents aged 15-59 years between 1964 and 1996 were extracted from the population-based Ontario Cancer Registry. Annual rates of testicular cancer for the 2 histologic groups were analysed by means of log-linear regression to estimate average annual percent change. RESULTS: Between 1964 and 1996 the incidence of testicular germ cell cancer increased by 59.4%, from 4.01 to 6.39 per 100,000. This corresponded to an average annual increase of about 2% for both nonseminoma and seminoma. The relative increase in incidence was greatest in the lowest age group (15-29 years) for both histologic groups, although the data suggest that the incidence of nonseminoma cancer in this age group began to decline in the early 1990s. The increase in incidence appears to be due to a birth cohort effect, with more recent cohorts of men at increased risk. INTERPRETATION: The rise in the incidence of testicular germ cell cancer, not only in Ontario but also in many developed countries, requires investigation. The search for explanatory factors should focus on exposures whose prevalence may have increased over the past few decades and that are common enough to affect population incidence. The similarity of trends for seminoma and nonseminoma cancer suggests that the underlying risk factors are likely the same.  相似文献   

6.
BackgroundPopulation based cancer registration provides a critical role in disease surveillance in terms of incidence, survival, cancer cluster investigations and prevalence trends, and therefore high levels of completeness and timeliness are required. This study estimates completeness and variation between early and late registrations in the N. Ireland Cancer Registry (NICR) and assesses the implications for reporting cancer incidence and for registry-based research.MethodsTwo main approaches assessed completeness. For the period 2010–2012, incidence reported in the first year of data publication was compared to incidence reported in subsequent years until 2015. Demographic characteristics and survival of incident cases ascertained before the first publication year were compared to those ascertained in subsequent years. The flow method approach was used to estimate completeness annually after the incident year.ResultsOverall incidence for all cancers increased between the first year of data publication and subsequent years up to 2015, irrespective of year of diagnosis. Late registrations had poorer survival. The flow method approach estimated the completeness of case ascertainment of NICR data to be 96% complete at five years for all cancers combined.ConclusionThe estimated completeness levels for the NICR are comparable to other high quality cancer registries internationally. While data timeliness has little impact on incidence estimates, delays in registration may have implications for specific research studies into incidence and survival. This means that improvements in the timeliness of reporting should be a target for all registries but not at the expense of completeness.  相似文献   

7.
Summary

A survey was made during 1986 of the longitudinal distribution of macrophytes in the River Wear (N-E. England) in order to make comparisons with surveys in 1966 and 1976. The presence or absence of species recognizable with the naked eye was recorded in 1986 for 74 of the possible 211 0.5-km lengths of river. In contrast to the marked differences between 1966 and 1976, changes since 1976 were minor; many were probably merely a reflection of recent flow events. The most clear-cut difference was the loss of most of the Elodea canadensis population. The only other change in records which may reflect a longer-term environmental change was a marked increase in the moss Amblystegium riparium, a species characteristically associated with organic pollution.  相似文献   

8.
There are few formally documented proficiency testing programs for cytology laboratories, and those that have been documented are not entirely comparable in format. The first of three papers documenting a mandatory universal proficiency testing program for cytology laboratories in the Province of Ontario, Canada, presents data on the structure and function of the participating laboratories (including a comparison of the data for 1974 and 1980) and on the organization of the testing model (including selection of terminology, construction and use of the survey and assessment of responses). In 1980, of the 463 medical laboratories in Ontario, 91 of 222 hospital laboratories and 65 of 216 nonhospital laboratories were licensed in cytology. In that year, the 156 cytology laboratories processed 1.48 million cytology specimens, 92% of which were gynecologic. Hospital laboratories processed 87.5% of the nongynecologic cytology specimens and 30% of the gynecologic cytology specimens. These proportions have been virtually constant for several years. Between 1974 and 1980, there was a trend in Ontario to fewer laboratories processing less than 5,000 cytology specimens per annum. Subsequent papers in this series describe the results of the initial surveys in this program and a precision study to evaluate the consistency of reporting by individual laboratories.  相似文献   

9.
Response consistency was examined by linking the records of women interviewed in the 1982 Sri Lanka Contraceptive Prevalence Survey with records from the same individuals followed up 3 years later. Seventy-eight percent of women reported identical year of birth in the two surveys, but only 58% were consistent for age at marriage. Data on sterilisation and number of children born were highly reliable, but wives' reports on husband's age and education were relatively weak. Multivariate analysis of the effects of socioeconomic factors on consistency in age reporting confirms that education is the most influential factor related to consistency, followed by religion and husband's occupation.  相似文献   

10.
Past studies have shown that personal subjective happiness is associated with various macro- and micro-level background factors, including environmental conditions, such as weather and the economic situation, and personal health behaviors, such as smoking and exercise. We contribute to this literature of happiness studies by using a geospatial approach to examine both macro and micro links to personal happiness. Our geospatial approach incorporates two major global datasets: representative national survey data from the International Social Survey Program (ISSP) and corresponding world weather data from the National Oceanic and Atmospheric Administration (NOAA). After processing and filtering 55,081 records of ISSP 2011 survey data from 32 countries, we extracted 5,420 records from China and 25,441 records from 28 other countries. Sensitivity analyses of different intervals for average weather variables showed that macro-level conditions, including temperature, wind speed, elevation, and GDP, are positively correlated with happiness. To distinguish the effects of weather conditions on happiness in different seasons, we also adopted climate zone and seasonal variables. The micro-level analysis indicated that better health status and eating more vegetables or fruits are highly associated with happiness. Never engaging in physical activity appears to make people less happy. The findings suggest that weather conditions, economic situations, and personal health behaviors are all correlated with levels of happiness.  相似文献   

11.
Incidence of malignancy among close relatives was used to evaluate the relationship of early age at diagnosis and familial cancer predisposition in a general population of cancer patients. The occurrence of cancer and other conditions in families of more than 1,350 randomly selected patients with a wide variety of malignancies was ascertained. Each patient was assigned to one of four study groups based on comparison of his age at diagnosis with the distribution of ages at diagnosis for his cancer site compiled by the Third National Cancer Survey. These groups consisted of patients whose ages at diagnosis were in: (1) the lowest decile, (2) the median decile, (3) above the median decile, and (4) between the lowest and median deciles. Person-years and calendar time at risk were calculated for first-degree relatives in each group. The numbers of cancers expected among these relatives were calculated using age- and time-specific incidence rates of a standard population. Statistical analysis of (1) the numbers of reported vs. expected cancers in relatives and (2) the numbers of families reporting cancer in parents or siblings of patients showed that a familial tendency to develop cancer exists in this randomly selected population of cancer patients, regardless of age at onset of malignancy in the proband. Conversely, early age at diagnosis of cancer may indicate genetic predisposition to malignancy only in exceptional cases.  相似文献   

12.
Donald J. McCulloch 《CMAJ》1966,94(5):235-237
A program of case-centred seminars in psychiatry designed for general practitioners was begun in Ontario during 1965. It came into being as the result of the cooperative endeavour of the Ontario Chapter, College of General Practice, the Ontario Psychiatric Association and the Division of Postgraduate Medicine, University of Toronto. The program was conducted on a regional rather than on a centralized basis. No general practitioner had to travel more than 30 miles to his seminar, thus ensuring regular weekly attendance for an average of 12 weeks. The Ontario Chapter recruited the general practitioners, the Psychiatric Association selected appropriate regional psychiatrists, and the University gave a brief preliminary course for these psychiatrists. Nineteen separate groups were formed in 13 different Ontario cities, with an average total weekly attendance of 120. A review conference of participating psychiatrists and general practitioners, held in November 1965, developed plans for renewal and extension of the program for 1966. This approach seems especially appropriate for large geographic regions with scattered populations.  相似文献   

13.
Cancer registries collect cancer incidence data that can be used to calculate incidence rates in a population and track changes over time. For incidence rates to be accurate, it is critical that diagnosed cases be reported in a timely manner. Registries typically allow a fixed amount of time (e.g. two years) for diagnosed cases to be reported before releasing the initial case counts for a particular diagnosis year. Inevitably, however, additional cases are reported after the initial counts are released; these extra cases are included in subsequent releases that become more complete over time, while incidence rates based on earlier releases will underestimate the true rates. Statistical methods have been developed to estimate the distribution of reporting delay (the amount of time until a diagnosed case is reported) and to correct incidence rates for underestimation due to reporting delay. Since the observed reporting delays must be less than the length of time the registry has been collecting data, most methods estimate a truncated delay distribution. These methods can be applied to a group of registries that began collecting data in the same diagnosis year. In this paper, we extend the methods to two groups of registries that began collecting data in two different diagnosis years (so that the delay distributions are truncated at different times). We apply the proposed method to data from the National Cancer Institute's Surveillance Epidemiology and End Results (SEER) program, a consortium of U.S. cancer registries that includes nine registries with data collection beginning in 1981 and four registries with data collection beginning in 1992. We use the method to obtain delay‐adjusted incidence rates for melanoma, liver cancer, and Hodgkin lymphoma.  相似文献   

14.
BackgroundPrevious studies have explored population-level smoking trends and the incidence of lung cancer, but none has jointly modeled them. This study modeled the relationship between smoking rate and incidence of lung cancer, by gender, in the U.S. adult population and estimated the lag time between changes in smoking trend and changes in incidence trends.MethodsThe annual total numbers of smokers, by gender, were obtained from the database of the National Health Interview Survey (NHIS) program of the Centers for Disease Control and Prevention (CDC) for the years 1976 through 2018. The population-level incidence data for lung and bronchus cancers, by gender and five-year age group, were obtained for the same years from the Surveillance, Epidemiology, and End Results (SEER) program database of the National Cancer Institute. A Bayesian joinpoint statistical model, assuming Poisson errors, was developed to explore the relationship between smoking and lung cancer incidence in the time trend.ResultsThe model estimates and predicts the rate of change of incidence in the time trend, adjusting for expected smoking rate in the population, age, and gender. It shows that smoking trend is a strong predictor of incidence trend and predicts that rates will be roughly equal for males and females in the year 2023, then the incidence rate for females will exceed that of males. In addition, the model estimates the lag time between smoking and incidence to be 8.079 years.ConclusionsBecause there is a three-year delay in reporting smoking related data and a four-year delay for incidence data, this model provides valuable predictions of smoking rate and associated lung cancer incidence before the data are available. By recognizing differing trends by gender, the model will inform gender specific aspects of public health policy related to tobacco use and its impact on lung cancer incidence.  相似文献   

15.
Studies of the colonization and spread of invasive species improves our understanding of key concepts in population biology as well as informs control and prevention efforts. The characean green alga Nitellopsis obtusa (starry stonewort) is rare in its native Eurasian range but listed by the United States Geological Survey (USGS) as an aggressive invasive in North America. First documented in North America in 1978 from New York, United States, it has since been reported from numerous inland lakes from Minnesota to Vermont, and from Lake Ontario and inland lakes in southern Ontario, Canada. While the ecological impacts of N. obtusa are not clearly understood in its invasive range, initial results show negative environmental effects. We have discovered a liquid‐preserved herbarium specimen that predates the 1978 records by at least 4 years, and is the first confirmed record of N. obtusa in Québec.  相似文献   

16.
The European Commission Habitats Directive requires that changes in the conservation status of designated species are monitored. Nocturnal and elusive species are difficult to count directly and thus population trajectories are inferred by variation in the incidence of field signs. Presence/absence techniques are, however, vulnerable to Type II errors (false negatives). The Eurasian otter (Lutra lutra), listed by the IUCN as ‘near threatened’, is monitored throughout Europe using the ‘Standard Otter Survey’ method. We explored the reliability of this approach by analysing species incidence at 1,229 sites throughout Ireland. Naïve species incidence was 72 % [95 % confidence interval (CI), 69–75 %] with variation affected significantly by survey team and, at running freshwater sites, the number of bridges present and rainfall during the month, and most notably during the 7 days, prior to survey. Rainfall had no effect on static freshwater sites or the coast. Marginal estimated mean species incidence derived from a GLM assuming the β coefficient of the survey team associated with the highest prevalence, no rainfall in the week prior to survey and sites that had multiple bridges, was 94 % [95 %CI 78–97 %]. We demonstrate that bias and error in binary wildlife surveys can have a major impact on a conservation assessment even when conducted on an apparently well-known species in a developed country with good infrastructure and a long history of similar ecological studies. Our results provide empirical evidence for further criticisms of the Standard Otter Survey method calling into question its value in monitoring changes in otter populations throughout Europe.  相似文献   

17.
E A Clarke  N Kreiger  R F Spengler 《CMAJ》1984,131(6):553-556
A follow-up study of 7535 women in Ontario was carried out to assess the occurrence of second primary cancers following the treatment of invasive carcinoma of the cervix between 1960 and 1975. The study was part of a larger international investigation of late radiation effects in patients with cervical cancer. Data were collected on the date and the type of treatment for cervical cancer and on the occurrence of second primary cancers diagnosed before 1980. Observed and expected numbers of second primary cancers, the latter determined according to Ontario incidence rates, were compared for individual sites and for all sites combined. There were significantly more primary cancers of the lung than expected (64 v. 15.52) but significantly fewer second primary cancers of the breast (56 v. 105.01) and colon (27 v. 43.31). Overall, there were significantly fewer (p less than 0.05) observed second primary cancers than expected (280 v. 394). Although the median follow-up period was less than 10 years there was no marked evidence of an excess of radiation-induced second primary cancers.  相似文献   

18.
Surveys serve as an important source of information on key anthropometric characteristics such as body height or weight in the population. Such data are often obtained by directly asking respondents to report those values. Numerous studies have examined measurement errors in this context by comparing reported to measured values. However, little is known on the role of interviewers on the prevalence of irregularities in anthropometric survey data. In this study, we explore such interviewer effects in two ways. First, we use data from the US National Health and Nutrition Examination Survey and the UK Household Longitudinal Study to evaluate whether differences between reported and measured values are clustered within interviewers. Second, we investigate changes in adult self-reported height over survey waves in two German large-scale panel surveys. Here, we exploit that height should be constant over time for the majority of adult age groups. In both analyses, we use multilevel location-scale models to identify interviewers who enhance reporting errors and interviewers for whom unlikely height changes over waves occur frequently. Our results reveal that interviewers can play a prominent role in differences between reported and measured height values and changes in reported height over survey waves. We further provide an analysis of the consequences of height misreporting on substantive regression coefficients where we especially focus on the role of interviewers who reinforce reporting errors and unlikely height changes.  相似文献   

19.
Brunke AJ  Marshall SA 《ZooKeys》2011,(75):29-68
Staphylinidae (Rove Beetles) from northeastern North America deposited in the University of Guelph Insect Collection (Ontario, Canada) were curated from 2008-2010 by the first author. The identification of this material has resulted in the recognition of thirty-five new provincial or state records, six new Canadian records, one new record for the United States and two new records for eastern Canada. All records are for subfamilies other than Aleocharinae and Pselaphinae, which will be treated in future publications as collaborative projects. Range expansions of ten exotic species to additional provinces and states are reported. The known distributions of each species in northeastern North America are summarized and presented as maps, and those species with a distinctive habitus are illustrated with color photographs. Genitalia and/or secondary sexual characters are illustrated for those species currently only identifiable on the basis of dissected males. The majority of the new records are in groups that have been recently revised, demonstrating the importance of curation and local insect surveys to the understanding of biodiversity, even for taxa and areas considered 'relatively well-known'.  相似文献   

20.
ABSTRACT Mourning doves (Zenaida macroura) are surveyed in North America with a Call-Count Survey (CCS) and the North American Breeding Bird Survey (BBS). Analyses in recent years have identified inconsistencies in results between surveys, and a need exists to analyze the surveys using modern methods and examine possible causes of differences in survey results. Call-Count Survey observers collect separate information on number of doves heard and number of doves seen during counting, whereas BBS observers record one index containing all doves observed. We used hierarchical log-linear models to estimate trend and annual indices of abundance for 1966–2007 from BBS data, CCS-heard data, and CCS-seen data. Trend estimates from analyses provided inconsistent results for several states and for eastern and central dove-management units. We examined differential effects of change in land use and noise-related disturbance on the CCS indices. Changes in noise-related disturbance along CCS routes had a larger influence on the heard index than on the seen index, but association analyses among states of changes in temperature and of amounts of developed land suggest that CCS indices are differentially influenced by changes in these environmental features. Our hierarchical model should be used to estimate population change from dove surveys, because it provides an efficient framework for estimating population trends from dove indices while controlling for environmental features that differentially influence the indices.  相似文献   

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