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G Salkeld

Publications and source records attributed to G Salkeld.

36 records · Page 2Linked to original sources
PubMed1998

Best estimate of the magnitude of mortality due to occupational exposure to hazardous substances.

OBJECTIVES: With a proportionate attributable risk approach, to estimate the magnitude of premature mortality induced by exposure to hazardous substances in the Australian workforce. METHODS: Estimates of the magnitude of mortality induced by exposure to hazardous substances in the Australian work-force were calculated by the proportionate attributable risk approach after careful consideration of options for methodological refinements. The main data sources used were unit mortality datasets (individual deidentified death records), and tabulations when these were unavailable. RESULTS: The estimated number of deaths that occurred in Australia each year from occupational exposure to hazardous substances was 2290; 78% of these were men. The rate of mortality attributable to occupational exposure to hazardous substances was three to four times greater in male workers than in female workers. Male (productive) person-years of life lost (PYLL) were generally eight times higher than female PYLL. Cancer was the prime cause of death, followed by renal, cardiovascular, neurological, and chronic respiratory disease. Acute toxic episodes accounted for a small proportion of mortality but yielded a much larger proportion of PYLL, reflecting the relatively young ages of those who experienced fatal effects. CONCLUSIONS: Although national estimates of the proportions of mortality attributable to occupational exposure to hazardous substances seemed to be validly derived, uncertainties remain associated with the lack of an empirical basis for derivation of proportionate risk fractions used in the calculations. The finding of an appreciable burden of mortality that is attributable to past occupational exposure to hazardous substances emphasises the necessity for occupational health and safety authorities to measure and reduce worksite exposures. There is also an incentive to encourage the construction of appropriately designed cohort studies across industries and occupational groupings so that, ultimately, risk estimates may be directly calculated and applied to total workforce data for the definitive estimation of the magnitude of harm induced by occupational exposure to hazardous substances.

Australia↗
PubMed1998

Intensive case management: a cost-effectiveness analysis.

OBJECTIVE: The objective of this study was to compare the outcomes and costs of intensive case management with routine case management for a group of severely disabled patients with a mental illness. METHOD: A cost-effectiveness analysis was conducted alongside a randomised controlled trial. Seventy-three patients, who reside in the eastern suburbs of Sydney, were randomly allocated to either intensive or routine case management. Staff providing intensive case management and substantially lower caseloads than staff providing routine case management. The main health outcome measured was patients' level of functioning as measured by the Life Skills Profile. Costing data were collected from hospital services, mental health services, general health services, community services and informal carers. RESULTS: At 12 months, outcome and costing data were analysed on 58 patients and hospitalisation data were analysed on 68 patients. Significantly more patients in the intensive case management group remained in treatment (chi 2 = 6.00, df = 1, p < 0.01) and showed a clinically significant improvement in functioning from baseline to 12 months (chi 2 = 4.50, df = 1, p < 0.05). The mean cost per patient was $7745 more in the intensive group than in the routine group (t = 1.49, df = 56, p > 0.01) over 12 months. The cost-effectiveness ratio indicated a cost of $27,661 per year for one additional patient in the intensive case management group to make a clinically significant improvement in functioning. CONCLUSION: Intensive case management led to an increased rate of retention in treatment and a clinically significant improvement in functioning. Further comparative cost-effectiveness studies are required to determine whether $27,661 per year for one patient to make a clinically significant improvement in functioning is a cost-effective use of mental health resources.

Adolescent↗
PubMed1997

The cost-effectiveness of a cardiovascular risk reduction program in general practice.

An economic evaluation was conducted alongside a randomised controlled trial of two lifestyle interventions and a routine care (control) group to assess the cost-effectiveness of a general practice-based lifestyle change program for patients with risk factors for cardiovascular disease. Routine care was the base case comparator because it represents 'current therapy' for cardiovascular disease (CVD). A 'no care' control group was not considered a clinically acceptable alternative to lifestyle interventions. The interventions consisted of an education guide and video for GPs to assess individual patient risk factors and plan a program for risk factor behavior change. Each patient received a risk factor assessment, education materials, a series of videos to watch on lifestyle behaviors and some patients received a self-help booklet. Eighty-two general practitioners were randomised from 75 general practices in Sydney's Western Metropolitan Region to (i) routine care (n = 25), (ii) video group (n = 29) or (iii) video + self help group (n = 28). GPs enrolled patients into the trial who met selection criteria for being at risk of CVD. There were 255 patients in the routine care (control) group, 270 in the video (intervention) group and 232 in the video + self help (intervention) group enrolled in the trial. Outcome measures included patient risk factor status: blood pressure, body mass index, cholesterol and smoking status at entry to trial and after 1 year. Changes in risk factors were used to estimate quality adjusted life years (QALYs) gained. One hundred and thirty patients in the routine care group, 199 in the video group and 155 in the video + self help group remained in the trial at the 12-month review and had complete data. The cost per QALY for males ranged from $AUD152,000 to 204,000. Further analysis suggests that a program targeted at 'high risk' males would cost approximately $30,000 per QALY. The lifestyle interventions had no significant effect on cardiovascular risk factors when compared to routine patient care. There remains insufficient evidence that lifestyle programs conducted in general practices are effective. Resources for general practice-based lifestyle programs may be better spent on high risk patients who are contemplating changes in risk factor behaviours.

Australia↗
PubMed1996

The measurement of utility in multiphase health states.

To examine the validity of the additive quality-adjusted life year model used to evaluate a multiphase health state, data from a pilot study of mammography were used to determine whether the values assigned to a multiphase postmastectomy health state could be estimated from a combination of the independently rated constituent health state values. The results suggest that they cannot.

Adult↗
PubMed1996

Health care expenditure and life expectancy in Australia: how well do we perform?

The Australian health care system consists of mixed public and private financing underpinned by Medicare, a universal government-run insurance scheme paid through taxation (and levy) on income. Australia has improved its ranking for life expectancy (at birth) since 1960, and in 1990 ranked ninth and seventh of 24 countries for females and males respectively; this is ahead of the United States and United Kingdom, and approximately equal to Canada. Australian hospital bed supply and utilisation are average, after deletion of day-only cases. The proportion of gross domestic product (GDP) spent on health, in relation to GDP per capita (adjusted for purchasing power), in Australia in 1990 was average, and the prices for health care from 1975 to 1990 did not increase when adjusted for inflation. Although 68 per cent of health expenditure emanates from public sources in Australia, this is lower than in the majority of European countries and Canada. Some countries are doing poorly (such as the United States, with lower than average life expectancy and higher than predicted health expenditure) and some countries are doing well (with higher than average life expectancy and lower than predicted health expenditure; for example, Japan). Australia has higher than average life expectancy and only slightly higher than predicted health expenditure per capita. Although the Australian system could be improved, there are no indications that radical changes are required. The relatively high life expectancy in Australia can be attributed to favourable social and economic conditions, successful public health programs, and the availability of universal quality health care.

Australia↗
PubMed1996

Cost-effectiveness analysis of screening by faecal occult blood testing for colorectal cancer in Australia.

The incremental costs and effects of annual faecal occult blood test screening in Australia were modelled for a hypothetical cohort of 1000 persons offered screening or not offered screening. Incremental costs and effects were estimated as the differences in direct health care costs (Australian costs) and years of life remaining between the annual-screen group and the control (no screen) group, based on the published results of the Minnesota randomised controlled trial. The cost per life year saved was $24,660. The greatest source of variability in the cost-effectiveness ratio is the effectiveness of screening. The 95 percent confidence interval for cumulative mortality in the annual-screen group is 3.86 to 7.9 per 1000, assuming the control rate is fixed at 8.83 per 1000. With this confidence interval, the cost per life year saved ranges from $12,695 to $67,848. The cost-effectiveness ratio increases to $48,000 if no mortality benefit is assumed beyond the end of the trial follow-up period, 13 years. The results are sensitive to the cost of colonoscopy (at $400 per colonoscopy, the cost per life year saved is $12,319) and the false-positive rate. The cost-effectiveness of colorectal cancer screening is comparable with that of other screening programs but further evidence is needed on the efficacy of screening. Whether the benefits of colorectal cancer screening outweigh the harm and costs needs to be more certain before more resources are committed to mass screening. Health policy planners should initiate planning for Australian pilot projects in the event that the efficacy of screening is confirmed by two current studies.

Australia↗
PubMed1995

A critical review of health-related economic evaluations in Australia: implications for health policy.

In Australia, as in many other countries, economic evaluation is increasingly seen by health care policy makers as a useful aid to priority setting and resource allocation. In Australia, economic evaluation is now a requirement for new drugs to be listed on the Pharmaceutical Benefits Scheme which provides a government subsidy on the price of listed drugs for purchasers. Yet, despite recognition of the importance of economic evaluation by policy makers, there is a paucity of published evaluations in Australia. We reviewed all of the 33 health-related economic evaluations conducted in Australia and subsequently published since 1978. This study assesses how well informed decision makers might be if they used the results and conclusions of published economic evaluations as an aid to resource allocation. The review highlights several issues: (i) it is difficult to interpret the conclusions or assess the generalisability of individual papers without information on the context of the original study; (ii) the choice of comparator(s) was often unexplained and most papers did not employ marginal analysis; (iii) in the absence of marginal analysis, the comparability of cost-effectiveness ratios in league tables must be questioned as well as the completeness (were all the relevant alternatives included?) of studies; and (iv) the quality of effectiveness evidence varies enormously, with some authors content to use the best available evidence (even if it is of poor quality). The development of standards for economic evaluation methods might ensure a more consistent and scientific approach to evaluative work, but they cannot guarantee it. A more concerted effort to disseminate the principles and methods of economic evaluation to policy makers and non-economist evaluators might be a more important precursor to improving the credibility and usefulness of economic evaluations in priority setting.

Australia↗
PubMed1995

The potential benefits and harms of screening for colorectal cancer.

Australian guidelines for colorectal cancer screening for average-risk populations vary from recommendations for annual screening by faecal occult blood testing for those over 40 years to recommendations that screening may be appropriate if requested by an informed patient aged 50 to 75 years. There are five large screening trials, of which three have published mortality data. A meta-analysis of the mortality data suggests a 19 per cent reduction in colorectal cancer mortality (95 per cent confidence intervals 0.68 to 0.96) with Hemoccult screening. Because of the width of the confidence interval, decisions about the magnitude of the effect of screening should await further trial results, which should be available in the next few years. In the interim, we should examine issues of harm and costs in Australia. For example, in the major trials, over 80 per cent of positive results have been falsely positive and have required invasive investigation. Estimates of the cost-effectiveness of screening for the Australian health system are not yet available and are essential. If the benefits of screening outweight the harms and costs, a successful screening program would require provision of screening infrastructure and appropriate information to target populations, quality control for screening tests and investigations, recall mechanisms to ensure appropriate follow-up of persons with positive results and the active participation of the Australian public and health practitioners.

Adult↗
PubMed1995

Increasing response rates in telephone surveys: a randomized trial.

BACKGROUND: Sampling frames and mode of contact and administration of questionnaires are important factors contributing to response rates and selection bias in population-based research. The purpose of this paper is to evaluate whether contact by mail before contact by telephone increases response rate, and to assess the concurrent validity of telephone surveys for collecting health research and service data. METHODS: Two thousand households were randomly selected from electronic white pages. Half were randomly allocated to receive or not to receive an explanatory letter before telephone contact. Interviewers were blinded to whether a household received a letter. Respondents aged 18 years or over were randomly selected from within each household using a Kish grid and interviewed by telephone. RESULTS: The overall response rate was 68 per cent [confidence interval (CI) 66-70]. The response rate of those who received the letter was 76 per cent (CI 73-79), and of those who did not receive the letter was 60 per cent (CI 56-63). Use of the Kish grid to select randomly a respondent decreased the response rate by less than 10 per cent. The internal validity of the data was as follows: in a 10 per cent sub-sample, the Kish grid had been correctly applied in 93 per cent of households, and in 99 per cent of households the exclusion criteria had been correctly adhered to. The external validity was as follows: comparisons with data obtained from the same reference population using similar instruments administered face-to-face revealed no meaningful or significant differences in population estimates. CONCLUSIONS: Mail-out before telephone contact greatly increases response rates at low cost. Telephone surveys can yield valid, useful data for health research and service evaluation.

Adult↗
PubMed1994

Will early detection of breast cancer reduce the costs of treatment?

A substantial investment in resources is required to provide a population-based mammography screening program. At the same time, screening may also reduce the costs of treating breast cancer. Empirical evidence to support such cost savings, however, is limited. This paper presents a simulation of the impact on treatment costs of a population-based mammography screening program in New South Wales. A 1991 cohort of women aged 45 to 69 years is followed for the period 1991 to 2023. With two-yearly screening, the present value of the total health service costs for this cohort would be approximately $112 million. Primary treatment, at $60 million, would cost $5 million more with screening than without. Treatment for advanced stages of the disease would cost $22 million less. Overall, this analysis suggests that savings in treatment costs are relatively small in relation to the overall resource requirements of organised screening.

Aged↗
PubMed1993

Cost-effectiveness of mammographic screening in Australia.

The purpose of this research was to estimate the cost-effectiveness of mammographic screening to supplement the results of the National Evaluation of Breast Cancer Screening which identified the mortality benefit as the most sensitive parameter. This appraisal used a different computer model, MISCAN, which models the effects of introducing a national screening program into a previously unscreened population, rather than basing estimates on the assumption of a fully established program. For the 40 to 49 age group a mortality reduction of 8 per cent was assumed, rather than the 30 per cent estimate utilised in the National Evaluation. The revised estimate is based on the two Swedish trials (Malmo and WE). New estimates for treatment costs were also incorporated into the MISCAN model. The cost-effectiveness of the policy recommended in the National Evaluation Report, $11,000 per life year saved with two-yearly screening of women over 40, is estimated by the MISCAN model to be $20,300. These differences arise partly from the difference in mortality effects for the 40 to 49 age group, but also from differences inherent in the steady-state and dynamic population approaches to modelling premature deaths averted. The MISCAN results confirm that screening for women over 50 is more cost-effective than screening women under 50. Screening all women aged 50 to 69 every two to three years is reasonable value for money. For women aged 40 to 49 the mortality benefit and cost-effectiveness is less clear, and it would be prudent to allow screening in this group until further evidence is available.

Adult↗
PubMed1992

A cost utility analysis of mammography screening in Australia.

Cost utility analysis is the preferred method of analysis when quality of life instead is an important outcome of the project being appraised. However, there are several methodological issues to be resolved in implementing cost utility analysis, including whether to use generalised measures or direct disease specific outcome assessment, the choice of measurement technique, and the combination of different health states. Screening for breast cancer meets this criterion as mammographic screening has been shown to reduce mortality; and it is said that earlier treatment frequently results in less radical surgery so that women are offered the additional benefit of improved quality of life. Australia, like many other countries, has been debating whether to introduce a national mammographic screening programme. This paper presents the results of a cost utility analysis of breast cancer screening using an approach to measuring outcome, Healthy Year Equivalents, developed within this study to resolve these problems. Descriptions of breast cancer quality of life were developed from surveys of women with breast cancer, health professionals and the published literature. The time trade off technique was then used to derive values for breast cancer treatment outcomes in a survey of women in Sydney, Australia. Respondents included women with breast cancer and women who had not had breast cancer. Testing of (i) the effect of prognosis on the value attached to a health scenario; and (ii) whether the value attached to a health scenario remains constant over time has been reported. The estimate of the net costs of screening are reported. The costs of breast cancer screening include the screening programme itself, the further investigations and the subsequent treatment of breast cancer cases. Breast cancer is treated in the absence of screening, many commentators claim earlier treatment is costly but there is little evidence. Therefore we have investigated current patterns of breast cancer treatment, current use of investigations for women presenting with symptoms and current use of covert mammography screening. The results are extrapolated to obtain estimates of the costs and outcomes presented as cost per healthy year equivalent. This analysis produces important information for the Australian policy debate over mammography. It also contributes to the development of cost utility analysis and the approach developed here can be applied more generally.

Australia↗
PubMed1990

Counting the costs of mammography screening: first year results from the Sydney study.

Population-based mammography screening is a highly specialized service which aims to improve the early detection of breast cancer. This is achieved through the installation of a dedicated mix of medical technology and professional skills. It is therefore a resource-intensive activity so the benefits foregone by deploying these resources for mammography screening ought to be determined to investigate the relative efficiency of such a commitment. This paper describes the costing methodology used in the evaluation of the Sydney Breast X-ray Programme and presents the health service costs for the first 12 months of operation. In the first year when attendance was under 5000 it cost $118.93 to screen a woman, $13,817 to detect a cancer and $18,720 to detect an impalpable cancer. However, costs are expected to fall in subsequent years as attendance reaches capacity level. The first screening round will detect prevalent cancers; costs will change with subsequent screening rounds as incident cancers are detected. We are cautious in extrapolating the costs of a national programme from these results. However, on the basis of our data and disregarding treatment costs, a national programme which screened 70% of all Australian women over the age of 45 years every two years would add between $60 million and $100 million to the national health bill each year.

Aged↗
PubMed1990

Patient education policy and practice in Australian hospitals.

In Australia little is known of the quality and range of patient education programs or their level of support. A national survey was conducted to establish a baseline of the number of programs being conducted, the level of administrative support and the sophistication of practice. This survey shows that most hospitals in Australia conduct some patient education programs. Teaching and metropolitan public hospitals conduct the most, 95% and 88%, respectively, private hospitals the least, 47%. The programs conducted mainly cover chronic health problems such as diabetes (80% of all hospitals offering programs), heart disease (52%) and cancer (36%). The main reason given for not conducting education programs is lack of trained staff (59%). Of the programs which are conducted only half are planned. Most of the hospitals surveyed had few of the administrative components found to be necessary to support planned, patient education programs. The two most common administrative components were documentation in patient notes (48% of hospitals conducting programs) and a resource center (34%).

Australia↗
PubMed1989

The management of oesophageal carcinoma: radiotherapy or surgery? Cost considerations.

A cost comparison has been made between two treatment modalities used with curative intent for carcinoma of the oesophagus, for 144 patients seen between December 1979 and December 1985. Forty-two patients were selected for radical oesophagectomy. In this paper these are compared with 50 patients who underwent radical radiotherapy. The median survival of both groups was identical (12 months). The remaining 52 patients underwent a variety of palliative procedures and are not considered further. Components of management were identified and costed on the basis of direct resource use by the hospital. Surgically treated patients on average cost $A13,638 in 1987 dollars, whereas those treated by radiotherapy cost $A3533. The major factors accounting for this cost difference were the necessary perioperative intensive management in the surgical group, the inevitable perioperative complications and the subsequent prolonged hospitalization of a proportion of patients. The cost of the management of the complications of radiation therapy are included but were not a major factor in overall costs for the irradiated group. This cost differential must influence the continuation of current strategies in which radical surgery, rather than irradiation, is the selected routine curative approach for oesophageal cancer particularly in the absence of evidence of higher survival.

Adenocarcinoma↗
PubMedDate not supplied

Adherence to occupational therapist recommendations for home modifications for falls prevention.

OBJECTIVE: This study examined adherence to home modification recommendations made by an occupational therapist and attempted to identify predictors of adherence. METHOD: An experienced occupational therapist visited the homes of 178 people (mean age = 764 years) to evaluate for and recommend appropriate home modifications for falls prevention. One year later, a research assistant visited these persons' homes to assess adherence. RESULTS: At least one home modification was recommended in 150 of the 178 homes visited. The most common recommendations were to remove mats and throw rugs (48%), to change footwear (24%), and to use a nonslip bathmat (21%). In the 121 homes revisited after 12 months, 419 home modifications had been recommended, and 216 (52%) were met with partial or complete adherence. The only significant predictors of adherence were a belief that home modifications can prevent falls and having help at home from relatives. CONCLUSION: A major barrier to adherence to home modification recommendations is that many older people do not believe that home modifications can reduce their risk of falling.

Accidental Falls↗
PubMedDate not supplied

Feasibility study of the early detection and treatment of renal disease by mass screening.

AIM: To determine whether mass screening for proteinuria may be worthwhile in the detection of early renal disease in Australians. METHODS: A feasibility study was conducted using systematic review, meta-analysis and cost-effectiveness methods. RESULTS: End-stage renal disease (ESRD) develops in about 1500 Australians each year. Of these, about 1000 are over 50 years of age (an incidence of about 200 per million, per year). Proteinuria, which is present in about 5% of the general population, confers an approximately 15-fold increased risk for ESRD. Twelve randomized trials of angiotensin-converting enzyme inhibitors (ACEi), in 1943 patients with varying degrees of renal impairment, hypertension and proteinuria, showed that the risk of developing ESRD can be reduced by about 30% over a 2- to 3-year period. In a general-practice-based screening model involving: (i) an opportunistic single dipstick test for protein, (ii) a confirming 24-h urine test for protein and (iii) commencement of ACEi in appropriate individuals, 20 000 people over 50 years of age would need to be screened to prevent one case of ESRD. To achieve this, approximately 100 people would need to be treated with ACEi for 2 to 3 years, and 1,000 would need to have a 24-h urine protein test (and of these, 700 would be false positives). Such a strategy may save health dollars but some critical research questions are still unanswered. What is an individual's risk of developing ESRD, given values for proteinuria, blood pressure and renal function? What is the benefit of ACEi in screen-detected cases, which are at low risk of ESRD? What psychological and physical harm is caused by screening, including the specific renal investigations and treatments that follow on from proteinuria detection? CONCLUSIONS: Given available data, screening middle-aged and older Australians for proteinuria and treating some with ACEi is, at best, a promising primary prevention strategy for preventing ESRD. However, a large population-based cohort study, with nested trial of ACEi, is still required to evaluate whether this model of screening for renal disease does more harm than good.

Aged↗