Stephenson 1989.

Methods	Design: parallel group randomized trial Duration of study: 1989 Follow‐up: 180 days
Participants	Country: Kenya Setting: school Number included in study: 17 Age: 6–16 years Sex: 96 boys, 75 girls Inclusion criteria: all available children in the lower grades (Standards I and II) in Mvindeni Primary School in Kwale District, Coast Province, Kenya Exclusion criteria: severe anaemia at stool examination 1 (haemoglobin < 8.0 g/dL) Lost at follow‐up: 21 (12.3%) Number positive for A lumbricoides: 73 Number included in review: 73
Interventions	Treatment strategy: screening and treat all included participants Group 1: albendazole 200 mg 2 tablets single dose (n = 34) Group 2: placebo (n = 39)
Outcomes	Outcomes included:Ascaris prevalence pre‐ and post‐treatment, AM and GM epg Outcomes not included in review: anthropometric measures, anthelmintic efficacy for T trichiura and hookworm
Notes	Diagnostic technique: modified Kato‐Katz Funding support: Smith Kline & French Laboratories, Ltd., and the Edna McConnellClark Foundation
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	Quote: "the children were allocated at random within sex to albendazole (A) or placebo (PL) groups and treated."
Allocation concealment (selection bias)	Unclear risk	Details not reported.
Blinding of participants and personnel (performance bias) All outcomes	Low risk	Quote: "Control group received identical placebo."
Blinding of outcome assessment (detection bias) All outcomes	Low risk	Quote: "examinations were carried out with the same team of worker and were done in a blind fashion."
Incomplete outcome data (attrition bias) All outcomes	Low risk	21 (12.3%) participants lost at follow‐up and not included in analysis.
Selective reporting (reporting bias)	High risk	Adverse events not reported.
Other bias	Unclear risk	Financial support: Smith Kline & French Laboratories, Ltd.