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Table 1 Assumptions used in estimations of lives saved from Global Fund-supported service deliveries.

From: Lives saved by Global Fund-supported HIV/AIDS, tuberculosis and malaria programs: estimation approach and results between 2003 and end-2007

Service Mortality reduction based on population coverage Population coverage estimated from service deliveries Other assumptions
ARV Survival of people in need of ARV [25, 26]: with ARV: 85% by 12 months, 95% over each next year without treatment: 50% by 12 months, 0% by 24 months.} Regional estimates of the average number of life-years gained per patient-year of (Global Fund-supported) ARV, derived by applying the Spectrum model [26] to UNAIDS estimates of national HIV prevalence, HIV mortality and ARV coverage (see Table 2) [24]. All people put on ARV are in need of ARV
Those on ARV as of December 2004 started treatment in 2004 (rather than earlier)Of people starting ARV in a given calendar year, starting dates are evenly distributed over that calendar year.
Region-specific 95% URs on mortality estimates from the Spectrum model [25, 26]
DOTS Death rates for newly detected smear-positive cases (WHO Stop TB department, unpublished data):
HIV-positive: country-specific (cross-country average 11%; 95% UR 6-21%)
HIV-negative: country-specific (cross-country average 11%; 95% UR 6-20%)
Scenario (a) - No TB treatment:
HIV-positive: country-specific (cross-country average 83%; 95% UR 70-99%)
HIV-negative: country-specific (cross-country average 70%; 95% UR 55-75%)
Scenario (b) - non-DOTS treatment:
HIV-positive: country-specific (cross-country average 31%; 95% UR 21-43%)
HIV-negative: country-specific (cross-country average 24%; 95% UR 15-34%)
All smear-positive cases reported as detected are DOTS-treated
Half of lives saved occur in the year of reported case detection, and half in the next year.
For programs not reporting the smear status of new cases, 50% were assumed to be smear-positive
Proportions of smear-positive TB cases that are HIV-positive are country-specific estimates, with a cross-country average of 12.3% (95% UR 10-15%) in 2006 [28].
ITNs All-cause under-5 mortality falls by 5.5 (95% UR 3.4-7.7) per 1000 child-years of protection by ITNs, in areas of stable endemic falciparum malaria [29] Each ITN distributed in a country with stable endemic falciparum malaria protects on average 0.73 child under-5 at risk [31].
Effective lifespan of an ITN is 1.5 years.
→ Average of 1.1 child-year (0.55-2.2) of protection per ITN distributed, over an ITN's lifetime
ITNs reported in a given calendar year count as providing protection for half of that year and (a maximum of) 1.0 year thereafter.
  1. Abbreviations: ARV = antiretroviral treatment; DOTS = directly observed treatment, short course; ITN = insecticide-treated mosquito net (including long-lasting insecticide nets). Numbers in brackets are 95% uncertainty ranges (UR).
  2. Note: For ARV, in view of its life-extending but non-curative nature, 'lives saved' should be read to mean: the difference between cumulative deaths with and without ARV, i.e. the deaths averted or postponed due to ARV by Global Fund-supported programmes, over the reference period between 2003 and December 2007.