Sources of error and bias in methods of fertility estimation contingent on the P/F ratio in a time of declining fertility and rising mortality

Almost all commonly used indirect fertility estimation methods rely on the P/F ratio. As originally conceived, the ratio compares cumulated cohort fertility with cumulated period fertility on the basis of three, fairly strong, assumptions. The intention of this paper is to interrogate what happens to the results produced by the P/F ratio method as each of these three assumptions is violated, first independently, and then concurrently. These investigations are important given the generally poor quality of census data collected in developing countries, particularly sub-Saharan Africa, and the radically altering demographic conditions associated with a generalised HIV/AIDS epidemic in the region.AIDS/HIV, developing countries, estimation, fertility, indirect techniques

Does the 2008 HSRC survey indicate a turning tide of HIV prevalence in children, teenagers and the youth?

Recently the HSRC released its report on the results of its third and most recent household prevalence survey. The main conclusion of their analysis is that “some solid progress has been made in the fight against the disease in the past few years, especially among teenagers and children”. In particular the authors conclude: • that HIV prevalence at national level has decreased amongst children aged 2-14, from 5.6% in 2002 to 2.5% in 2008, • that there was a substantial decrease in incidence in 2008 in comparison to 2002 and 2005, especially for the single age groups 15, 16, 17, 18, and 19, • that HIV prevalence has decreased amongst youth aged 15-24 from 10.3% in 2005 to 8.6% in 2008, and • that HIV prevalence among adults aged 15-49 has declined between 2002 and 2008 in the Western Cape, Gauteng, Northern Cape and the Free State, “with the largest decline of 7.9 (sic) percentage points in the Western Cape”. How reliable are the results from the survey and how reasonable are these conclusions

Modelling the demographic impact of HIV/AIDS in South Africa and the likely impact of interventions

This paper describes an approach to incorporating the impact of HIV/AIDS and the effects of HIV/AIDS prevention and treatment programmes into a cohort component projection model of the South African population. The modelled HIV-positive population is divided into clinical and treatment stages, and it is demonstrated that the age profile and morbidity profile of the HIV-positive population is changing significantly over time. HIV/AIDS is projected to have a substantial demographic impact in South Africa. Prevention programmes - social marketing, voluntary counselling and testing, prevention of mother-to-child transmission and improved treatment for sexually transmitted diseases - are unlikely to reduce AIDS mortality significantly in the short term. However, more immediate reductions in mortality can be achieved when antiretroviral treatment is introduced.antiretroviral treatment, demographic impact, HIV/AIDS prevention, simulation model, South Africa

Child mortality in South Africa - we have lost touch

No Abstract. South African Medical Journal Vol. 97 (8) 2007: pp. 582-58

Levels of mortality of the South African aged population using the method of extinct generations

Abstract This paper investigates the reasons for the levelling off of the mortality estimates at the oldest age groups and the possibility of estimating the level of the mortality rates at these ages.The research applies the method of extinct generations to estimate indirectly the population numbers at the oldest-old age groups (75 to 100+) using data on reported deaths alone, and hence, the mortality rates. After observing that the estimated mortality rates are levelling off with age at the advanced ages (age 90 to 100+) due to age exaggeration in both the deaths and the population, the Gompertz curve was fitted to the estimated mortality rates at age groups 75, 80 and 85. Our estimates are generally lower but close to the estimates derived by Dorrington et al., (2004) and the estimates from the United Nations Population Division (UNPD) and the US Census Bureau (USCB) population projections.Keywords: Old age mortality; extinct generations; age exaggeration; completeness; South AfricaRésumé Cet article examine les raisons de la stabilisation des estimations de la mortalité des groupes d’âgede plus vieux et la possibilité d’estimer le niveau de taux de mortalité à ces âges. La recherche applique la méthode des générations éteintespour estimer indirectement les nombres de la population des groupes d’age de plus vieux (75 à 100+) en utilisant seuls les données sur lesdécèsrapportés et donc le taux de mortalité. Après avoir abservé que le taux de mortalité estimés sont nivellés avec l'âge à des âges avancés (âge 90 à 100+) dû à l’exaggeration dans les décès ainsi que dans la poplation, la courbe de Gompertz était ajusté au taux de mortalité estimé aux groupes d’age 75, 80, 85. Nos estimations sont généralement plus faibles mais à proximités des estimations dérivées par Dorrington et al., (2004) et les estimations de la Division de la Population des Nations Unies (UNPD: United Nations Population Division) et le projection de populations du Bureau du recensement des États-Unis (USCB: US Census Bureau)

Child mortality in South Africa - we have lost touch

Reducing child mortality is, appropriately, one of the eight Millennium Development Goals (MDGs) for reducing poverty and inequality in the world. The target for this goal is to reduce child mortality by 2015 by two-thirds of the rate in 1990. Monitoring child mortality rates, however, is posing a challenge for low- and middle-income countries. Estimates that many countries, particularly in Africa, use to track progress in meeting this goal have to be extrapolated from earlier empirical data, since there are no up-to-date data. Despite great strides that have been made in improving population health statistics, South Africa is unfortunately no exception. The most recent reasonably reliable estimates of child mortality for South Africa are for the mid-1990s, in other words 10 years out of date

Has HIV prevalence peaked in South Africa? - Can the report on the latest antenatal survey be trusted to answer this question?

On the weekend of Friday 29 August, the National Department of Health placed their report on the results of the 2007 national antenatal survey, carried out a little over 10 months ago, on their website.1 The Department uses these results (showing an overall HIV prevalence of 28%) to reinforce those of the previous survey2 and argue that 'South Africa may be making some real progress in its response to the HIV epidemic' and that the 'South African HIV epidemic is on a downward trend'. While this may or may not be true, in order for one to infer a trend in indicators from a sequence of surveys they need to be comparable, year on year, with one another. Unfortunately this is not the case with the antenatal surveys of the past 2 years

Estimating adult mortality in Zambia using information on survival of parents from surveys

The aim of this study is to derive estimates of level of and trend in adult mortality in Zambia. To do this the study applies the standard orphanhood method to the data on survivorship of parents from various Zambia Demographic and Health and Living Conditions Monitoring Surveys to estimate 10q25 and 15q25 for females; and 10q35 for males, and hence, the probability of a 15 year old dying before age 60 (45q15). The study finds that the orphanhood method captures some of the trend but fails to provide definitive estimates of mortality. The levels of female adult mortality between ages 25 and 35 years have remained constant at about 15 per cent from the mid-1990s. The female mortality rate between ages 25 and 40 years has also remained constant, at between 20 per cent and 25 per cent since 2000. Adult male mortality between ages 35 and 45 years increased in the mid-1990s and has remained between 20 per cent and 25 per cent from the late 1990s to late 2000s. Adult mortality, 45q15, for both males and females, has increased over time and has stabilised at about 60 per cent for males and 50 per cent for females. These adult mortality rates are comparable to estimates from other sources

The level and trends of child mortality in South Africa, 1996-2006

Abstract The lack of reliable data for child mortality estimation since 1998 has meant that child mortality rates for South Africa have not been updated for almost ten years. This study makes use of the Community Survey data of 2007 and adaptation of the correction to the children ever born/children surviving method suggested by Ward and Zaba (2009) to estimate current rates of infant and child mortality and establishes trends in childhood mortality between 1996 and 2006. The study found that infant mortality rates have been almost constant at around 50 deaths per 1000 live births while under-five mortality rates are found to have increased from just below 70 deaths per 1000 live births in 1996 to around 75 deaths per 1000 live births in 2006.Keywords: Infant mortality; under-five mortality; HIV/AIDS prevalence; Brass Technique; Trussel variant; South Africa.Resume L'absence de données fiables sur l’estimation de la mortalité infantile en Afrique du Sud n'ont pas été mise à jour depuis presque dix ans à partir de 1998. Notre étude a établit les estimations sur les taux de mortalité infantile ainsi que la mortalité des enfants de moins de cinq ans. Notre analyse a utilisé les données de l’Enquête communautaire de 2007, recensement de 2001 et les résultats sur les recherches antérieurs depuis 1996.Les résultats montrent que le taux de mortalité infantile sont restés presque con- stant, environ 50 décès pour 1000 naissances vivantes tandis que pour moins de cinq le taux de mortalité ont augmenté, passant de 70 décès pour 1000 naissances vivants en 1996 à 75 décès pour 1000 naissances vivants en 2006.Mots clés: Mortalité infantile, Mortalité des moins de Cinq ans, Prevalence du VIH/SIDA, Technique de Brass, Variance de Trussel, Afrique du Su

The burden of disease attributable to sexually transmitted infections in South Africa in 2000

Objectives. To estimate the burden of disease attributable to sexually transmitted infections (STis) in South Africa, to identify the factors contributing to this burden, and to review successes and failures in reducing this burden.Design. Years of life lost (YLL) and years lived with disability (YLD) were estimated using different approaches for HIV I AIDS, other STis and cervical cancer. Burden in respect of HIV I AIDS was estimated using the ASSA2002 model, and for the other diseases the revised national burden of disease estimates for 2000 based on 1996 cause-of-death data were used. The ASSA2002 model was used to estimate numbers of AIDS deaths under different prevention and treatment scenarios.Setting. South Africa. Outcome measures. Deaths, YLL and disability-adjusted life years (DALYs) associated with HIV I AIDS, other STis and cervical cancer. Results. STis accounted for more than 26% of all deaths and over 5 million DALYs in 2000 and over 98% of this burden was due to HIV I AIDS. A combination of social, behavioural and biological conditions contribute to this burden. HIV I AIDS mortality and morbidity are estimated to have increased significantly since 2000, and the future change in this burden is largely dependent on the extent to which antiretroviral treatment and HIV prevention programmes are introduced. 2.5 million AIDS deaths could be prevented by 2015 if high levels of access to antiretroviral treatment are achieved.Conclusion. South Africa faces one of the largest STI epidemics in the world. A multifaceted strategy to prevent and treat STis is needed, and burden of disease assessments should look beyond the role of 'unsafe sex' when attributing this disease burden to risk factors