Implementing Impact Evaluations of Malaria Control Interventions: Process, Lessons Learned, and Recommendations.

As funding for malaria control increased considerably over the past 10 years resulting in the expanded coverage of malaria control interventions, so did the need to measure the impact of these investments on malaria morbidity and mortality. Members of the Roll Back Malaria (RBM) Partnership undertook impact evaluations of malaria control programs at a time when there was little guidance in terms of the process for conducting an impact evaluation of a national-level malaria control program. The President's Malaria Initiative (PMI), as a member of the RBM Partnership, has provided financial and technical support for impact evaluations in 13 countries to date. On the basis of these experiences, PMI and its partners have developed a streamlined process for conducting the evaluations with a set of lessons learned and recommendations. Chief among these are: to ensure country ownership and involvement in the evaluations; to engage stakeholders throughout the process; to coordinate evaluations among interested partners to avoid duplication of efforts; to tailor the evaluation to the particular country context; to develop a standard methodology for the evaluations and a streamlined process for completion within a reasonable time; and to develop tailored dissemination products on the evaluation for a broad range of stakeholders. These key lessons learned and resulting recommendations will guide future impact evaluations of malaria control programs and other health programs.

Impact of Malaria Control on Mortality and Anemia among Tanzanian Children Less than Five Years of Age, 1999-2010.

BACKGROUND: Mainland Tanzania scaled up multiple malaria control interventions between 1999 and 2010. We evaluated whether, and to what extent, reductions in all-cause under-five child mortality (U5CM) tracked with malaria control intensification during this period. METHODS: Four nationally representative household surveys permitted trend analysis for malaria intervention coverage, severe anemia (hemoglobin <8 g/dL) prevalence (SAP) among children 6-59 months, and U5CM rates stratified by background characteristics, age, and malaria endemicity. Prevalence of contextual factors (e.g., vaccination, nutrition) likely to influence U5CM were also assessed. Population attributable risk percentage (PAR%) estimates for malaria interventions and contextual factors that changed over time were used to estimate magnitude of impact on U5CM. RESULTS: Household ownership of insecticide-treated nets (ITNs) rose from near zero in 1999 to 64% (95% CI, 61.7-65.2) in 2010. Intermittent preventive treatment of malaria in pregnancy reached 26% (95% CI, 23.6-28.0) by 2010. Sulfadoxine-pyrimethamine replaced chloroquine in 2002 and artemisinin-based combination therapy was introduced in 2007. SAP among children 6-59 months declined 50% between 2005 (11.1%; 95% CI, 10.0-12.3%) and 2010 (5.5%; 95% CI, 4.7-6.4%) and U5CM declined by 45% between baseline (1995-9) and endpoint (2005-9), from 148 to 81 deaths/1000 live births, respectively. Mortality declined 55% among children 1-23 months of age in higher malaria endemicity areas. A large reduction in U5CM was attributable to ITNs (PAR% = 11) with other malaria interventions adding further gains. Multiple contextual factors also contributed to survival gains. CONCLUSION: Marked declines in U5CM occurred in Tanzania between 1999 and 2010 with high impact from ITNs and ACTs. High-risk children (1-24 months of age in high malaria endemicity) experienced the greatest declines in mortality and SAP. Malaria control should remain a policy priority to sustain and further accelerate progress in child survival.

Data Resource Profile: The sentinel panel of districts: Tanzania's national platform for health impact evaluation.

The Sentinel Panel of Districts (SPD) consists of 23 districts selected to provide nationally representative data on demographic and health indicators in Tanzania. The SPD has two arms: SAVVY and FBIS. SAVVY (SAmple Vital registration with Verbal autopsY) is a demographic surveillance system that provides nationally representative estimates of mortalities based on age, sex, residence and zone. SAVVY covers over 805 000 persons, or about 2% of the Tanzania mainland population, and uses repeat household census every 4-5 years, with ongoing reporting of births, deaths and causes of deaths. The FBIS (Facility-Based Information System) collects routine national health management information system data. These health service use data are collected monthly at all public and private health facilities in SPD districts, i.e. about 35% of all facilities in Mainland Tanzania. Both SAVVY and FBIS systems are capable of generating supplementary information from nested periodic surveys. Additional information about the design of the SPD is available online: access to some of SPD's aggregate data can be requested by sending an e-mail to [hmasanja@ihi.or.tz].

Child survival gains in Tanzania: analysis of data from demographic and health surveys.

BACKGROUND: A recent national survey in Tanzania reported that mortality in children younger than 5 years dropped by 24% over the 5 years between 2000 and 2004. We aimed to investigate yearly changes to identify what might have contributed to this reduction and to investigate the prospects for meeting the Millennium Development Goal for child survival (MDG 4). METHODS: We analysed data from the four demographic and health surveys done in Tanzania since 1990 to generate estimates of mortality in children younger than 5 years for every 1-year period before each survey back to 1990. We estimated trends in mortality between 1990 and 2004 by fitting Lowess regression, and forecasted trends in mortality in 2005 to 2015. We aimed to investigate contextual factors, whether part of Tanzania's health system or not, that could have affected child mortality. FINDINGS: Disaggregated estimates of mortality showed a sharp acceleration in the reduction in mortality in children younger than 5 years in Tanzania between 2000 and 2004. In 1990, the point estimate of mortality was 141.5 (95% CI 141.5-141.5) deaths per 1000 livebirths. This was reduced by 40%, to reach a point estimate of 83.2 (95% CI 70.1-96.3) deaths per 1000 livebirths in 2004. The change in absolute risk was 58.4 (95% CI 32.7-83.8; p<0.0001). Between 1999 and 2004 we noted important improvements in Tanzania's health system, including doubled public expenditure on health; decentralisation and sector-wide basket funding; and increased coverage of key child-survival interventions, such as integrated management of childhood illness, insecticide-treated nets, vitamin A supplementation, immunisation, and exclusive breastfeeding. Other determinants of child survival that are not related to the health system did not change between 1999 and 2004, except for a slow increase in the HIV/AIDS burden. INTERPRETATION: Tanzania could attain MDG 4 if this trend of improved child survival were to be sustained. Investment in health systems and scaling up interventions can produce rapid gains in child survival.