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Biomedical subjects

J L Botha

Publications and source records attributed to J L Botha.

At least 55 records · Page 3Linked to original sources
PubMed1989

Validity of the register of medical practitioners for manpower planning. Results and recommendations from a postal sample survey.

A postal survey was conducted to assess the validity of the register of medical practitioners held by the South African Medical and Dental Council. This register has been used by researchers as a data source for assessing the distribution of medical practitioners. The register is not adequate for this function unless adjusted by sample survey results. Crucially, it overestimates rural and homeland doctor resources. The survey also revealed under-representation of women as doctors (17% of all doctors are women) and as specialists (6% of all specialists are women) and unavailability due to retirement of registered doctors as service providers (6% of all registered doctors are retired), particularly in community health (24%). Collection of this information at annual registration is recommended, along with the establishment of an 'overseas' section of the South African register. Failure to implement these recommendations will seriously impede health services research.

Dentists↗
PubMed1989

Regression with an ordered categorical response.

A survey on Mseleni joint disease in South Africa involved the scoring of pelvic X-rays of women to measure osteoporosis. The scores were ordinal by construction and ranged from 0 to 12. It is standard practice to use ordinary regression techniques with an ordinal response that has that many categories. We give evidence for these data that the constraints on the response result in a misleading regression analysis. McCullagh's proportional-odds model is designed specifically for the regression analysis of ordinal data. We demonstrate the technique on these data, and show how it fills the gap between ordinary regression and logistic regression (for discrete data with two categories). In addition, we demonstrate non-parametric versions of these models that do not make any linearity assumptions about the regression function.

Adolescent↗
PubMed1988

An introduction to clinical epidemiology.

Clinical epidemiology is defined and its influence on methods of diagnosing and treating patients assessed. A plea is made for the wider application of such methods.

Clinical Competence↗
PubMed1988

The distribution of health needs and services in South Africa.

The authors recognize that social, economic and political factors play a larger role in determining public health policy than do epidemiological principles such as the analysis of needs, demand and supply. Nevertheless, demographic and mortality statistics, information from the 1983 registers of medical and dental practitioners, and that of nurses, as well as information on hospital beds were reviewed to describe health care requirements and resources in South Africa. The maldistribution observed in health needs and services closely parallel the divisions in South African society imposed by the apartheid policy. It is concluded that fundamental political change is required to reduce this maldistribution. The provision of preventive and promotive health services for children in African rural and peri-urban areas was identified as a health care requirement of high priority. It is thought that the need in these geographical regions might best be met by employing primary health care workers at a lower level of training than doctors with an accessible, supporting referral system. In addition, the quality of health care data being collected needs to be improved. It is suggested that both these problems be approached on a regional basis, and preferably under a single health authority, rather than the current fragmented health service.

Demography↗
PubMed1987

Osteopenia of the pelvis associated with Mseleni joint disease. Radiological aspects.

Mseleni joint disease, an endemic form of osteoarthritis (OA), is associated with osteopenia (OP). In a detailed investigation of the disorder, the degree of OP was assessed in 593 radiographs of the pelvis which were taken during surveys of four populations: rural blacks from Mseleni, rural blacks from Manguzi (a similar population to Mseleni), a black control group of rural Tswanas and a white control group from Johannesburg. Only females were included because the number of males in the rural populations was too small. The radiographic trabecular pattern was assessed at four sites: sacrum, ilium, pubis and ischium. Four grades were used: O = normal bone, 1 = minimal OP, 2 = definite OP, 3 = severe OP. The sum of the grades at the four sites made up the OP score for the individual. The OP scores increased with age in all groups, the age-specific mean OP scores did not differ in the non-OA subgroups of all four populations, and subgroups with OA had significantly higher age-specific mean OP scores than those without OA.

Adolescent↗
PubMed1986

How many doctors are needed in South Africa by 1990?

The 1983 register of medical and dental practitioners was used to describe the provincial and urban-rural distribution of non-specialist medical practitioners. The number of medical practitioners who will be registered in 1990 was estimated on the basis of current accrual and loss patterns. The number required by 1990 was estimated on the basis of the projected population growth using a linear prediction model in which the proportion of blacks resident in urban regions was varied. The requirements were based on doctor/population ratios either remaining as they were in 1980 or improving by 1990. We found that for South Africa there were 2 198 people per doctor. However, there were more people per doctor in rural regions than in urban regions, with the rural Cape Province the only rural region with fewer than 6 000 people per doctor. In black national states there were more than 14 000 people per doctor. There appears, therefore, to be a need for redistribution of medical practitioners to the rural regions. We estimated that, should doctor/population ratios in 1990 remain as they were in 1980 with only a modest increase in black urbanization, there would be enough medical practitioners registered in 1990 at current accrual rates. Should rural ratios be improved to 1:5 000 and urban ratios to 1:1 000 as proposed in the National Health Services Facility Plan, there will be fewer doctors registered than are needed in 1990, particularly if black urbanization increases markedly.(ABSTRACT TRUNCATED AT 250 WORDS)

Forecasting↗
PubMed1986

Familial hypercholesterolaemia--the need for adequate counselling and family tracing.

A search for the founder member(s) responsible for the familial hypercholesterolaemia (FH) gene(s) in the RSA inadvertently revealed the existence of a marriage which links two pedigrees in which FH occurs. This marriage could result in the birth of an FH homozygote child. The couple concerned should have--but had not--been informed of the implications of their union before their marriage. The importance of identifying individuals at risk through extensive tracing of families in which FH occurs and the relevance of subsequent counselling are illustrated.

Child↗
PubMed1986

Excess mortality from stomach cancer, lung cancer, and asbestosis and/or mesothelioma in crocidolite mining districts in South Africa.

To determine whether exposure to crocidolite is associated with excess mortality, the authors calculated standardized mortality ratios based on deaths in South African crocidolite mining districts from 1968 to 1980 for selected causes of death. Contiguous districts were used as controls. To take account of background geographic variability, they divided the control districts into groups of population size similar to those of the crocidolite mining districts. Standardized mortality ratios in crocidolite mining districts were elevated for asbestosis and/or mesothelioma, and cancer of the lung and stomach. These findings could not be explained by background geographic variability in mortality and are likely to be due to exposure to South African crocidolite during mining and milling or to environmental contamination. The increased standardized mortality ratios for stomach cancer are of particular interest, since excess deaths have not previously been shown in individuals exposed to crocidolite alone.

Adolescent↗