Geissbühler 2009 TZA

Methods	Trial design: Controlled before‐and‐after trial Type of cluster: Ward Cluster size: Total study population of 4761 Number of clusters in each arm: Intervention arm: three; control arm: 12 Adjusted for clustering? No
Participants	Age: 0 to five years Sex: Any Co‐morbidities and pregnancy: Any Primary outcome sample size (Parasite prevalence): 4450 participants Secondary outcome sample size (EIR): 268 sentinel sites (4 sites in each of 67 mitaa)
Interventions	Intervention: Larviciding Details of the intervention:                                                      Larviciding: Open (light‐exposed) larval habitats were treated with Bti water‐dispersible granules (VectoBac®, applied at 0.04g/m2 using knapsack sprayers) and Bti corn granules (VectoBac®, applied at 1 g/m2 by hand). Closed habitats (the main larval habitat of Culex quinquefaciatus, a nuisance‐biting mosquito) were treated with Bs corn cob granules (VectoLex®, applied at a dosage rate of 1 g/m2 by hand). Frequency of application: Larviciding of open habitats: weekly; closed habitats: every three months. Duration of intervention period: 12 months Who was responsible for LSM? Open habitats were treated by modestly paid members of the community, Mosquito Contro CORPs, each of which was assigned to a specific area (mtaa). An additional team of CORPs was responsible for treating closed habitats. CORPs reported to the Ward Office. Co‐interventions: None. However ITNs were used in the study area. Coverage: Non‐intervention area: 23.6% (year 1), 27.7% (year 2), 24.6% (year 3); Intervention area: 23.3% (year 1), 26.3% (year 2), 22.4% (year 3). Co‐interventions equal in each arm? Yes
Outcomes	1. Parasite prevalence (measured with randomized, cluster‐sampled household surveys in May to September 2004, November to July 2004, September 2005 to May 2006, July 2006 to March 2007, with parasite prevalence determined by microscopy). 2. EIR (measured by (1) human landing catch for 45 minutes of each hour from 6pm to 6am, at sentinel sites every four weeks, and (2) laboratory analysis of specimens for sporozoites).
Notes	Continent: Africa Country: Tanzania Ecosystem: Coastal Urban or rural: Urban Extensive or localized larval habitats: Localized Primary larval habitats: Man‐made habitats exposed to sunlight Transmission intensity: Low to moderate Transmission season(s): July to September Primary and secondary vector:An. gambiae s.l. Primary malaria parasite:P. falciparum Source of funding: Bill & Melinda Gates Foundation; Valent Biosciences Corporation; United States Centers for Disease Control and Prevention and United States Agency for International Development (Environmental Health Program, Dar es Salaam Mission and the President’s Malaria Initiative, all administered through Research Triangle International); Wellcome Trust.
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	High risk	Not randomly chosen.
Allocation concealment (selection bias)	High risk	Not randomly chosen.
Blinding of outcome assessment (detection bias) All outcomes	Low risk	Malaria prevalence determined by blinded reading of blood smears of randomly chosen individuals.
Blinding of participants and personnel (performance bias) All outcomes	High risk	Impossible to blind implementers to intervention.
Incomplete outcome data (attrition bias) All outcomes	Unclear risk	Individual patients not followed up therefore not possible to measure percentage loss to follow‐up.
Selective reporting (reporting bias)	High risk	All household members tested, but results presented only for children aged 0 to five years.
Baseline characteristics	Unclear risk	Baseline characteristics not specified.
Contamination	Low risk	Most of control clusters > 1 km from intervention clusters.
Incorrect analysis	Unclear risk	Cluster adjustment not applicable.
Other bias	High risk	High risk of confounding.