The quantification of alcohol-caused morbidity and mortality in Australia: the authors respond.
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Adult↗
Biomedical subjects
B K Armstrong
Publications and source records attributed to B K Armstrong.
The effects of surgical treatment on survival and local recurrence of cutaneous malignant melanoma.
All patients with a diagnosis of cutaneous malignant melanoma (CMM) in Western Australia from 1980 to 1981 were observed for up to 6 years to determine vital status and to detect the development of local recurrences of the primary lesion. Approximately 35% of all patients had their tumors excised with surgical margins of less than 1 cm. When compared with patients whose tumors were excised with margins of at least 2 cm, the fatality rate in those with narrow margins was slightly less (rate ratio, 0.60; 95% confidence interval [CI], 0.20% to 1.80% for margins of 5 to 9 mm; rate ratio, 0.69; 95% CI, 0.26% to 1.87% for margins of 1 to 4 mm); however, this difference could have been caused by chance alone. The risk of local recurrence within 5 years after diagnosis was 2% (95% CI, 1% to 4%). The risk was strongly related to age and tumor thickness, but did not appear to be influenced by the width of excision (greater than 1 cm versus less than 1 cm: rate ratio, 1.03; 95% CI, 0.25% to 4.34%). The apparent lack of effect could be caused by to chance alone because the number of local recurrences was small.
Adult↗
Wittenoom, Western Australia: a modern industrial disaster.
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Asbestosis↗
The role of the cancer registry in cancer control.
It has been accepted generally that the cancer registry has more of a 'back room' than a 'front line' role in cancer control, its particular responsibilities lying in description of cancer patterns, care, and outcome, in monitoring these variables in relation to control activities, and in providing a research database--often, for others to utilize. While readily justifiable, this prevailing concept of the cancer registry's role may not be sustainable in times of economic restraint. A survey of members of the International Association of Cancer Registries showed that most registries fit the accepted mold. Some, however, extend beyond it, particularly in the direct conduct of epidemiologic research and in the implementation of control programs, particularly screening. Sixteen percent appeared only to be collecting incidence statistics and may be at risk of economic rationalization. It would be consonant with their basic role and skills, and promote more rational cancer control, if cancer registries were to take on an expanded role, including direct participation in epidemiologic research, evaluation of interventions against cancer at the population level, situation analysis and cancer control planning, and implementation of aspects of cancer control--particularly coordination of screening--and monitoring the performance of cancer control programs. This expanded role could become the responsibility of specialized cancer control units of which cancer registration would be the central function.
Cancer Care Facilities↗
Lack of positive bias of the confounding effect of risk factors estimated by marginal aetiological fractions.
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Bias↗
Survival among patients with clinical stage I cutaneous malignant melanoma diagnosed in Western Australia in 1975/1976 and 1980/1981.
Five-year survival rates were slightly higher for patients with cutaneous malignant melanoma (CMM) diagnosed in Western Australia in 1980/1981 (89% in men and 95% in women) than in those whose melanomas were diagnosed in 1975/1976 (88% in men and 91% in women). The improvement in survival was probably due to a decrease in median tumor thickness from 1.29 mm in 1975/1976 to 0.77 mm in 1980/1981 because tumor thickness was the most important histologic index of prognosis. Tumor cell type and cross-sectional profile were the only other histologic characteristics that independently influenced fatality rates. Prognosis was significantly worse in males than in females and in patients with tumors on the posterior head and neck. Ten-year survival rates of patients whose melanomas were diagnosed in 1975/1976 was 82% in men and 87% in women, indicating that these patients continued to experience some excess mortality up to 10 years after diagnosis. The comparatively small improvement in prognosis in the 5-year period between these two groups suggests that survival might be expected to continue to improve only gradually unless there is a sharp absolute decrease in the number of thick tumors diagnosed.
Adolescent↗
Incidence of histologic types of uterine sarcoma in relation to menstrual and reproductive history.
To determine whether the occurrence of one or more histologic types of uterine sarcoma is related to events in a woman's reproductive life, a population-based case-control study was conducted. One-hundred sixty-seven women newly diagnosed with uterine sarcoma among residents of 6 geographic regions were compared to 208 women selected at random from the same populations with regard to histories of menstruation, pregnancy and childbearing, and breast feeding, as reported during a telephone interview. Compared to women whose menstrual periods began at age 13, women whose menses began earlier were at increased risk of leiomyosarcoma (OR = 2.0, 95% CI 0.9, 4.3); other histologic types were less strongly associated with early age at menarche. Women with leiomyosarcoma and endometrial stromal sarcoma, but not malignant mixed Müllerian tumors, tended to have ceased menstruating 2-3 years later than controls. None of the histologic types was clearly related to parity or to age at first live birth, but each was inversely related to age at last live birth. Associations were observed between leiomyosarcoma and histories of an induced abortion (OR = 4.2, 95% CI 1.2, 14.2) and of breast feeding after a live birth (OR = 0.5, 95% CI 0.3, 1.0); these relationships were not observed for other morphologic variants. These results suggest possible similarities and differences in menstrual and reproductive risk factors among histologic types of uterine sarcoma, and between these malignancies and the more common breast, endometrial and ovarian carcinomas.
Adult↗
Pigmentary and cutaneous risk factors for non-melanocytic skin cancer--a case-control study.
The roles of ethnic origin, pigmentary traits, sun sensitivity and other cutaneous characteristics as risk factors for basal-cell carcinoma (BCC) and squamous-cell carcinoma (SCC) were examined in a case-control study of prevalent and incident cases of histopathologically confirmed skin cancers. Two hundred and twenty six confirmed cases of BCC, 45 of SCC and 1,015 controls with no lesions were identified in a population-based survey of skin cancer in 1987 in Geraldton, Western Australia. The risk of both cancers was higher in native-born Australians than in migrants. The risk of BCC decreased with increasing age at arrival in Australia. Southern European ancestry was strongly protective against BCC (for any southern European grandparents) and SCC (no case of SCC had any grandparents of southern European origin). Inability to tan was the strongest pigmentary risk factor for both BCC and SCC. Among factors that incorporated a measure of sun exposure as well as sun sensitivity, freckling on the arm in childhood was important for both cancers, the number of moles on the back was important for BCC, and forearm skin colour and having a permanent colour difference between the neck and adjacent protected areas were important for SCC. Among measures of sun damage to the skin, solar elastosis of the neck was a strong risk factor for both BCC and SCC, loss of fine texture of the skin of the back of the hands (as measured by cutaneous microtopography) was important for BCC and telangiectasia of the face for SCC. When all important variables for each cancer were examined together in a single model with age, sex, migrant status or age at arrival in Australia, and ethnicity, in ability to tan, solar elastosis of the neck, and the number of moles on the back were independently significant risk factors for BCC and solar elastosis of the neck and having a permanent colour difference between the neck and adjacent protected areas were independently significant risk factors for SCC. The effects of age at arrival or migrant status and ethnic origin remained important in the models incorporating these factors. A history of ever having acne and a history of warts were protective for BCC and a history of acne was protective for SCC.
Adult↗
Smoking, exposure to crocidolite, and the incidence of lung cancer and asbestosis.
In 1979 all former workers from the Wittenoom asbestos industry who could be traced to an address were sent a questionnaire to determine smoking history. Occupational exposure to crocidolite was known from employment records. Of 2928 questionnaires sent, satisfactory replies were received from 2400 men and 149 women. Eighty per cent of these had smoked at some time and 50% were still smoking. Since that time 40 cases of lung cancer and 66 cases of compensatable asbestosis have occurred in this cohort. The incidence of both lung cancer and asbestosis was greatest in those subjects with the highest levels of exposure to crocidolite and in ex-smokers. Statistical modelling of the joint effects of these exposures on the incidence of each disease indicated that crocidolite exposure multiplied the rates of lung cancer due to smoking and that smoking has no measurable effect on the rates of asbestosis. There was also some evidence that the incidence rate of lung cancer is falling with time.
Asbestos↗
Skin cancer in Geraldton, Western Australia: a survey of incidence and prevalence.
A survey of the incidence and prevalence of non-melanocytic skin cancer in Geraldton, Western Australia, was undertaken in November 1987. All residents aged 40 to 64 years whose names were on the electoral roll on August 1, 1987 were invited to undergo a whole-body skin examination by a dermatologist. When a skin cancer was suspected, participants were referred for treatment to their usual medical practitioner. Subjects were asked to recall incident skin cancers over the preceding two years, and medical records were searched for confirmatory evidence. Histological confirmation of all lesions, both prevalent and incident, was sought and sections were obtained for a standardized review. The prevalence of confirmed non-melanocytic skin cancer in those aged 40 to 64 years was 7.0% in men and 4.7% in women. The prevalence of basal-cell carcinoma (BCC) was 6.5% in men and 4.5% in women while the prevalence of squamous-cell carcinoma (SCC) was 1.2% in men and 0.3% in women. The estimated incidence rate of non-melanocytic skin cancer in this age group was 1560 per 100,000 person-years. The estimated incidence rate of BCC in men was 1335 per 100,000 person-years, and in women 817 per 100,000, while in men the estimated incidence rate of SCC was 890 per 100,000 person-years, and in women it was 289 per 100,000 person-years.
Adult↗
Influence of education and advertising on the uptake of smoking by children.
How effective are peer-led programmes in preventing the uptake of smoking by children? In 1981, we conducted a randomized controlled trial of a school-based educational programme for the prevention of smoking in children who were in their seventh year at school. In this article, the reported results of two years of follow-up confirm an earlier report that both teacher-led and peer-led programmes resulted in a reduction, to about the same degree, in the uptake of smoking by girls, while only the teacher-led programme appeared to be effective in boys. In girls, both the teacher-led and peer-led programmes maintained their effects over the two years of follow-up with adjusted differences in prevalence rates of the uptake of smoking relative to the control group of -6.6% (95% CL, -17.3%, 4.0%) and -8.1% (95% CL, -18.9%, 2.7%), respectively, after two years. In boys, the effect of the teacher-led programme was reduced substantially by the second year with a difference in the prevalence rate of -2.8% (95% CL, -11.2%, 5.6%); for the peer-led programme the difference in the prevalence rate was +6.4% (95% CL, -3.6%, 16.4%). Other variables which had a significant effect on the smoking behaviour were the perceived response to cigarette advertising, parental and sibling smoking status, the perceived parental sanctions on smoking behaviour, selected peer influences and the intention to smoke. The children's perceived responses to cigarette advertising showed the strongest and most consistent evidence of an effect on the uptake of smoking by children who initially were non-smokers. After adjustment for the effects of other variables there was an excess of 15.0% (95% CL, 2.1%, 27.9%) in the prevalence rate of smoking after two years for girls who thought that they were influenced by advertising compared with those who did not. The corresponding difference for boys was 15.3% (95% CL, 4.0%, 26.6%). As smoking-prevention programmes only may delay the onset of smoking in children, it is important that legislative measures be introduced to reduce the effects of cigarette advertising.
Advertising↗
The incidence of malignant mesothelioma in Australia, 1947-1980.
Details of patients with malignant mesothelioma that was diagnosed in Australia before 1981 were obtained by searching all possible sources throughout Australia as far into the past as possible and up to and including 1980. The earliest patient with mesothelioma who was identified was diagnosed in Victoria in 1947. By 1980, 535 (81%) men and 123 (19%) women had been diagnosed with the disease; only 14 persons were aged less than 35 years at the time of diagnosis (the youngest person was 15 years of age). The incidence rate in subjects who were 35 years or older at diagnosis was less than 1.0 cases per million person-years until 1964-1968, and then it rose progressively to 15.5 cases per million person-years in 1979-1980. The highest rate (69.7 cases per million person-years) was observed in 65- to 74-year-old men in 1979-1980. The incidence rate in Western Australia was greater than were the rates in other states of Australia after the mid 1960s. Pleural mesotheliomas accounted for 88% of cases in which the site of the tumour was known; peritoneal mesotheliomas accounted for 10% of such cases and "other" sites for 2% of such cases. In 6% of cases the site was not specified. The exposure to asbestos was stated as "definite" in 59% of the cases with a recorded history of exposure: 8% of all the cases in the study had been exposed to crocidolite (blue asbestos) from Wittenoom Gorge in Western Australia. The age at diagnosis of patients with known exposure to asbestos was similar to that in those without known exposure. The increases in the incidence of malignant mesothelioma in Australia follow the published trends in the production and use of the amphibole varieties of asbestos in this country after a lag period of between 20 and 30 years.
Adolescent↗
A review of the effects of random measurement error on relative risk estimates in epidemiological studies.
Many articles in the recent epidemiological literature have discussed the effects of random error and misclassification on effect estimation, but many of these have been unclear and hard to follow. This paper reviews and interprets many of these and summarizes the use of the correlation coefficient in assessing the likely effect of measurement error on relative risk estimates for variables that are either continuous or ordered. A table of expected values of relative risks (RRs) calculated in different ways for different levels of random error is presented and the typically large expected attenuation in RR values is shown. The recommendation of taking repeated or multiple measurements whenever possible is endorsed.
Confounding Factors, Epidemiologic↗
An unjustified attack on "incidence"?
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Acute Disease↗
Trends in the incidence of myocardial infarction in Western Australia between 1971 and 1982.
Trends in the incidence of and mortality from myocardial infarction in Perth, Western Australia, were studied for the period 1971 to 1982. The estimated age-adjusted incidence rate of myocardial infarction fell by 24% in males and 37% in females over this period. The rate fell in each of six age-sex groups, but the proportional decrease in those aged less than 45 years was nearly double that in those aged 45 years and over, as it was in females compared with males and in fatal cases compared with nonfatal cases. Over 80% of the decline in mortality was in deaths outside hospital. This and seven other comparable studies all showed a net decrease in the estimated incidence of myocardial infarction in both sexes, with median annual decreases of 2% in males and 3% in females. It is concluded that the decline in the incidence of myocardial infarction contributed substantially to the observed decrease in ischemic heart disease mortality, and that the most plausible explanation for the decline in incidence is a reduction in the prevalence of risk factors for myocardial infarction.
Adult↗
Nuclear indices and survival in cutaneous melanoma.
Computerized video image analysis of Feulgen-stained paraffin sections was used to assess the relationships of nuclear DNA content and other nuclear morphological characteristics with survival from cutaneous melanoma. The results indicate that nuclear area and deviation from diploidy have effects on survival independent of tumor thickness and the age of the patient. Tumor thickness, however, remained the most important predictor of survival. Video image analysis of tissue sections, by virtue of its speed, simplicity, and accuracy, appears to be a potentially valuable prognostic method.
Age Factors↗
Natural history of pleural thickening after exposure to crocidolite.
Serial plain chest radiographs of 384 men who worked at the Wittenoom crocidolite mine and mill between 1943 and 1966 and who applied for pneumoconiosis compensation between 1948 and 1982 have been examined independently by two trained observers for pleural disease using the 1980 ILO-UICC classification of radiographs to record width and extent of pleural disease. Radiographs covering follow up periods of from two to 38 years were examined (median number of films per subject was nine). The degree of crocidolite exposure was estimated from employment records and a survey of airborne fibre concentrations performed in 1966. Agreement between the observers on the presence and degree of pleural disease in the final film for each subject was moderately close (Kendall's tau B = 0.62) and was least for subjects with thickening less than 5 mm in width. Diffuse pleural thickening extending for greater than 50% of the lateral chest wall was the most common type recorded by both observers. Minor pleural thickening frequently progressed in extent along the lateral chest wall but progression beyond 5 mm in thickness was less common. Pleural plaques were not seen to progress beyond their initial thickness or extent. The rate of onset of thickening in this population increased continually from the time of first exposure and also increased slightly with age. There was evidence that the level of total cumulative exposure to crocidolite increased the rate of onset of pleural thickening in the period between five and 15 years after first exposure. Rate of progression of established thickening was greatest in subjects who first developed thickening early after first exposure. The relative rate of progression decreased slowly with time from first signs of thickening and there was no evidence of any progression more than 15 years after onset.
Asbestos↗
Cancer mortality in relation to measures of occupational exposure to crocidolite at Wittenoom Gorge in Western Australia.
The separate and combined effects of duration and intensity of exposure to crocidolite on mortality from lung cancer, malignant mesothelioma, and stomach cancer were examined in 6506 male former crocidolite miners and millers at Wittenoom Gorge, Western Australia. Each subject who had died from lung cancer (92), mesothelioma (31), or stomach cancer (17) was matched with up to 20 control subjects of the same age who were not known to have died before the index subject. Relations of dose and time of exposure to crocidolite to risk of death were modelled by conditional logistic regression. For lung cancer, the best fitting multiplicative model was one which estimated a relative risk (RR) of 1.12 (95% CI 1.04-1.20) per year of exposure and 1.01 (95% CI 1.00-1.01) per fibre/ml. This was statistically indistinguishable from an additive model showing an increase in RR of 0.01045 (95% CI 0.008-0.020) per f/ml year. For mesothelioma the best fitting model appeared to be one estimating a RR of 24.9 (95% CI 3.51-1.77) per log year since first exposed and a RR of 10.5 (95% CI 3.12-35.1) if exposed for longer than six months. This was not distinguishable statistically from a model that showed mortality increasing as the fourth power of time since first exposed less the fourth power of time since last exposed. The effect of intensity of exposure on the RR for mesothelioma was only slight. There was no consistent effect of any measure of exposure to crocidolite on death from stomach cancer.
Asbestos↗