title: Cluster-randomised controlled trials of individual and combined water, sanitation, hygiene and nutritional interventions in rural Bangladesh and Kenya: the WASH Benefits study design and rationale.
abstract: BACKGROUND
  Enteric infections are common during the first years of life in low-income countries and contribute to growth faltering with long-term impairment of health and development. Water quality, sanitation, handwashing and nutritional interventions can independently reduce enteric infections and growth faltering. There is little evidence that directly compares the effects of these individual and combined interventions on diarrhoea and growth when delivered to infants and young children. The objective of the WASH Benefits study is to help fill this knowledge gap.
  
  
  METHODS
  WASH Benefits includes two cluster-randomised trials to assess improvements in water quality, sanitation, handwashing and child nutrition-alone and in combination-to rural households with pregnant women in Kenya and Bangladesh. Geographically matched clusters (groups of household compounds in Bangladesh and villages in Kenya) will be randomised to one of six intervention arms or control. Intervention arms include water quality, sanitation, handwashing, nutrition, combined water+sanitation+handwashing (WSH) and WSH+nutrition. The studies will enrol newborn children (N=5760 in Bangladesh and N=8000 in Kenya) and measure outcomes at 12 and 24 months after intervention delivery. Primary outcomes include child length-for-age Z-scores and caregiver-reported diarrhoea. Secondary outcomes include stunting prevalence, markers of environmental enteropathy and child development scores (verbal, motor and personal/social). We will estimate unadjusted and adjusted intention-to-treat effects using semiparametric estimators and permutation tests.
  
  
  BACKGROUND
  Study protocols have been reviewed and approved by human subjects review boards at the University of California, Berkeley, Stanford University, the International Centre for Diarrheal Disease Research, Bangladesh, the Kenya Medical Research Institute, and Innovations for Poverty Action. Independent data safety monitoring boards in each country oversee the trials. This study is funded by a grant from the Bill & Melinda Gates Foundation to the University of California, Berkeley.
  
  
  BACKGROUND
  Trial registration identifiers (http://www.clinicaltrials.gov): NCT01590095 (Bangladesh), NCT01704105 (Kenya).
authors.affiliation: School of Public Health, University of California, Berkeley, California, USA.
authors.forename: Benjamin F
authors.initials: BF
authors.lastname: Arnold
authors.forename: Clair
authors.initials: C
authors.lastname: Null
authors.forename: Stephen P
authors.initials: SP
authors.lastname: Luby
authors.forename: Leanne
authors.initials: L
authors.lastname: Unicomb
authors.forename: Christine P
authors.initials: CP
authors.lastname: Stewart
authors.forename: Kathryn G
authors.initials: KG
authors.lastname: Dewey
authors.forename: Tahmeed
authors.initials: T
authors.lastname: Ahmed
authors.forename: Sania
authors.initials: S
authors.lastname: Ashraf
authors.forename: Garret
authors.initials: G
authors.lastname: Christensen
authors.forename: Thomas
authors.initials: T
authors.lastname: Clasen
authors.forename: Holly N
authors.initials: HN
authors.lastname: Dentz
authors.forename: Lia C H
authors.initials: LC
authors.lastname: Fernald
authors.forename: Rashidul
authors.initials: R
authors.lastname: Haque
authors.forename: Alan E
authors.initials: AE
authors.lastname: Hubbard
authors.forename: Patricia
authors.initials: P
authors.lastname: Kariger
authors.forename: Elli
authors.initials: E
authors.lastname: Leontsini
authors.forename: Audrie
authors.initials: A
authors.lastname: Lin
authors.forename: Sammy M
authors.initials: SM
authors.lastname: Njenga
authors.forename: Amy J
authors.initials: AJ
authors.lastname: Pickering
authors.forename: Pavani K
authors.initials: PK
authors.lastname: Ram
authors.forename: Fahmida
authors.initials: F
authors.lastname: Tofail
authors.forename: Peter J
authors.initials: PJ
authors.lastname: Winch
authors.forename: John M
authors.initials: JM
authors.lastname: Colford
keywords: Drinking Water; Handwashing; Sanitation