Strategies to increase the ownership and use of insecticide-treated bednets to prevent malaria

Abstract

Background Malaria is a life-threatening parasitic disease and 40% of the world's population lives in areas affected by malaria. Insecticide-treated bednets (ITNs) effectively prevent malaria, however, barriers to their use have been identified. Objectives To assess the evidence on the effectiveness of available strategies that focus on delivery and appropriate use of ITNs. Search methods We searched the EPOC Register of Studies, CENTRAL, MEDLINE, EMBASE, HealthStar, CINAHL, PubMed, Science Citation Index, ProQuest Dissertations and Theses, African Index Medicus (AIM), World Health Organization Library and Information Networks for Knowledge (WHOLIS), LILACS, Virtual Health Library (VHL), and the World Health Organization Library Information System (WHOLIS). Initial searches were conducted in May 2011, updated in March 2012 and February 2013. Authors contacted organizations and individuals involved in ITN distribution programs or research to identify current initiatives, studies or unpublished data, and searched reference lists of relevant reviews and studies. Selection criteria Randomized controlled trials, non-randomized controlled trials, controlled before-after studies, and interrupted time series evaluating interventions focused on increasing ITN ownership and use were considered. The populations of interest were individuals in malariaendemic areas. Data collection and analysis Two authors independently screened studies to be included. They extracted data from the selected studies and assessed the risk of bias. When consensus was not reached, any disagreements were discussed with a third author. The magnitude of effect and quality of evidence for each outcome was assessed. Main results Of the 3032 records identified, 10 studies were included in this review. Effect of ITN cost on ownership: Four studies including 4566 households and another study comprising 424 participants evaluated the effect of ITN price on ownership. These studies suggest that providing free ITNs probably increases ITN ownership when compared to subsidized ITNs or ITNs offered at full market price. Effect of ITN Cost on appropriate use of ITNs: Three studies including 9968 households and another study comprising 259 individuals found that there is probably little or no difference in the use of ITNs when they are provided free, compared to providing subsidized ITNs or ITNs offered at full market price. Education: Five studies, including 12,637 households, assessed educational interventions regarding ITN use and concluded that education may increase the number of adults and children using ITNs (sleeping under ITNs) compared to no education. One study, including 519 households, assessed the effects of providing an incentive (an undisclosed prize) to promote ITN ownership and use, and found that incentives probably lead to little or no difference in ownership or use of ITNs, compared to not receiving an incentive. None of the included studies reported on adverse effects. Authors' conclusions Five studies examined the effect of price on ITN ownership and found moderate-certainty evidence that ownership was highest among the groups who received the ITN free versus those who purchased the ITN at any cost. In economic terms, this means that demand for ITNs is elastic with regard to price. However, once the ITN is supplied, the price paid for the ITN probably has little to no effect on its use; the four studies addressing this outcome failed to confirm the hypothesis that people who purchase nets will use them more than those who receive them at no cost. Educational interventions for promoting ITN use have an additional positive effect. However, the impact of different types or intensities of education is unknown.