ANNEX: STATISTICAL TABLES NOTES ON THE DATA
whose parents have died due to all causes or AIDS for past years based on the refined methodology.
Data sources and compilation
To achieve consistency and establish a comparative measurement of progress, trend analyses must be recalculated using only the newly generated estimates.
The data and analyses presented in this Sixth Stocktaking Report are derived from information in UNICEF global databases that are compiled from various sources. These include nationally representative data collected from household surveys – e.g., Demographic and Health Surveys, Multiple Indicator Cluster Surveys and Reproductive Health Surveys; national programme service statistics collected annually by UNAIDS, UNICEF and WHO through the Global AIDS Response Progress Reporting (GARPR) process: country estimates of HIV care and treatment needs modelled by UNAIDS and WHO in collaboration with countries; and the United Nations Population Division country estimates of the number of annual births. In 2013, UNAIDS, UNICEF and WHO collected HIV coverage data from national programmes worldwide, through the 2013 GARPR process, a reporting tool used to monitor and report on their national progress towards HIV and AIDS goals and targets. The tool typically comprises indicators to track progress towards universal access to HIV prevention, treatment and care, including HIV interventions for women and children such as preventing mother-to-child transmission and paediatric HIV care. The tool also collated updated household survey data on HIV knowledge and sexual behaviour. The GARPR replaces the Joint Reporting Tool on the health-sector response to HIV and AIDS and collected HIV programme data for the 12-month period of January–December 2013.
Estimates on HIV care and treatment needs of children and pregnant women In 2013, UNAIDS and WHO refined the HIV and AIDS estimation methodology to reflect more reliable data available from population-based surveys, expanded national sentinel surveillance systems and programme service statistics in a number of countries. As a result, UNAIDS has retrospectively generated new estimates for HIV prevalence, numbers of people living with HIV, paediatric HIV treatment needs and children
Similarly, global estimates of the number of children in need of antiretroviral therapy and the number of pregnant women living with HIV have been refined, and the coverage rates for 2005–2011 have thus been recalculated using the newly generated estimates. These estimates included the most recent country-reported data from 2012. The methods and assumptions of the UNAIDS and WHO estimation model continue to evolve and are regularly updated as new data become available. As a result, the estimated proportion of children (aged 0–14) who received antiretroviral therapy in 2012 is 34 per cent. It is not very different from the estimated coverage published in previous stocktaking reports. Any change in estimated coverage is not related to an increase or a decrease in the number of children in need of antiretroviral therapy receiving treatment, but to changes in the estimation methodology and in coverage of key HIV and AIDS programme interventions, particularly PMTCT. In light of these changes, 2012 coverage rates should not be compared with coverage figures published in previous versions of progress reports including the same data. For this reason, all estimates of paediatric antiretroviral therapy and antiretrovirals for PMTCT for previous years have been back-calculated for this year’s report. Overall, the differences between the newly generated estimates and previously published estimates are not related to trends over time, and are therefore not comparable. Nor are other revised estimates comparable to estimates published in previous years. Trends over time may be assessed, however, using new UNAIDS methodological revisions applied retrospectively to earlier HIV and AIDS data. More details about the data, reporting by specific countries and the methodology for HIV estimates can be found at <www.unaids.org>.
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