Howard 2007

Methods	Study design: controlled interrupted time series Study location: Kisii Central District, Western Kenya Study dates: October 2003 to October 2004 Transmission intensity: endemic but highly seasonal Malaria parasite species: not specified Primary vectors: An. gambiae s. l.,An. funestus Giles Breeding sites: abandoned fishponds Baseline data: October 2003 to January 2004
Participants	Not applicable
Interventions	Fish species: Oreochromis niloticus L. Indigenous fish species used: yes Fish source: local FD hatchery in Kisii town Populated sites: three abandoned fishponds, Pond A (104 m2), Pond C (128 m2), and Pond D (72 m2); 150 m distance from each other Restocked: no Co-interventions: none
Outcomes	Number of immature Anopheles per pond Density of immature Anopheles per pond Method: five larval dips (2.5 L total volume) randomly from edges of each pond, at least one dip/side, five to seven days/week
Source of funding	Government of Finland and BioVision
Notes	Climatic data for study period obtained from Kenya Agricultural Research Institute Study started with Pond B included, but as it was destroyed during the study period, the authors were unable to collect data for it for the requisite time period
Risk of bias
Bias	Authors' judgement	Support for judgement
Study design	High risk	Controlled interrupted time series study
Site selection	Low risk	"The site has three abandoned fishponds within 150 m of each other". Author communication: "We started with a Pond B but it got destroyed during the study period so we were unable to collect data for it for the requisite time"
Site allocation	Unclear risk	Unclear how treatment for each site was chosen
Blinding of outcome assessment (detection bias) All outcomes	Unclear risk	Unclear whether assessors were blinded to treatment
Baseline values	Low risk	Numbers of An. gambiae s. l. and An. funestus immatures comparable in Ponds A, C, and D
Number of sites	High risk	Probably inadequate as < five sites per group; control = one site, experimental = two sites