Table 2

Characteristics of included (quasi-)experimental studies

First author (year)Country/settingStudy designParticipantsSample sizeStudy time frameType of interventionControl situationOutcomes
Level of outcome assessmentEligible outcomesDefinition of outcomeFollow-up
Aung et al 42 (2016)India, ruralRCTHouseholds with one female cook >25 years who was neither pregnant at enrolment nor a current or previous smokerN=187; C=91; I=96Sept 2011–Aug 2012CDM approved single-pot ‘rocket-style’ biomass cookstoveThree-stone stovesHousehold24-hour PM2.5 exposure37 mm Teflon filters placed downstream of a cyclone with a 2.5 µm aerodynamic-diameter cut point connected to a battery-operated pump1 year
Bensch and Peters22 (2012)Senegal, ruralC-RCT (household level)Households with no previous access to improved cookstovesN=253 households; C=155 households; I=98 householdsNov 2009– Nov 2010Portable clay/metal firewood stove (Jambar)Three-stone stoves; traditional metal wood stovesHouseholdRespiratory system disease (cough, asthma, difficulty breathing); eye problemsSelf-reported symptoms1 year
Bensch and Peters23 (2015)Senegal, ruralC-RCT (household level)Households with no previous access to improved cookstovesN=253 households; C=155 households; I=98 householdsNov 2009–Nov 2010Portable clay/metal firewood stove (Jambar)Three-stone stoves and traditional metal wood stovesHousehold; individual (women responsible for cooking)Respiratory system disease (cough, asthma, difficulty breathing); eye problemsSelf-reported symptoms1 year
Burwen and Levine24 (2012)Ghana, ruralRCTOne woman per household (most frequently responsible for cooking)N=768; C=366; I=402Feb– May 2009Improved cookstove (unspecified)Traditional L-shaped or U-shaped three-stone fireIndividualCO exposure during cooking; cough; difficulty breathing; chest pain; excessive mucusCO: Gastec 1 DL CO Passive Diffusion tubes;
self-reported symptoms
8 months
Diaz et al 25 (2007)Guatemala, ruralRCTPregnant women or families with child <4 monthsGroup A: N=300; C=147; I=153
Group B: N=204; C=98; I=106
Oct 2002–Dec 2004Plancha stoveTraditional open fireIndividualSore eyes; exhaled COSore eyes assessed with a health questionnaire, reassessed every 6 months;
exhaled CO measured with a Micro Medical Micro CO monitor
12 months (group A); 18 months (group B)
Hanna et al 26 (2012)India, ruralC-RCT (household level)Eligibility criteria not reportedN=2651 households; first 1/3 within each village received stoves at start of project, second 1/3 received stove 2 years after the first wave and remaining households at end of the studySep 2006–Mar 2007; May 2009–Apr 2010ICS (ARTI)Traditional stoveIndividual (primary cooks, women and children)Exhaled CO; lung function; symptoms (cough, phlegm, wheezing, sore eyes, tightness in the chest); infant mortality; stillbirths and miscarriagesCO: Micro Medical CO monitor;
health symptoms and outcomes were self-reported;
lung function measured with spirometry
4 years
Hartinger et al 40 (2016)Peru, ruralC-RCT (community level)Children aged 6–35 months from households using solid fuelsN=503; C=253; I=250Sept 2008–Jan 2010OPTIMA-improved ventilated solid-fuel stoveUnventilated traditional stove or open fireIndividualARI; ALRI; chronic cough in children <36 monthsARI: child w/cough and/or difficulty breathing. ALRI: child w/ cough and/or difficulty breathing and raised resp. rate12 months
Jamali et al 21 (2017)Pakistan, ruralNRCTHouseholds and one woman (main cook) per householdSindh:
N=292; C=209; I=83
N=313; C=179; I=134
Mar– Sept 2014ChulhasTraditional three-stone stoveKitchen and individual (women responsible for cooking)Respiratory symptoms (chest tightness, shortness of breath, phlegm, asthma, cough); lung function (PEF); eye symptoms;
24-hour PM2.5 and CO exposure
Symptoms: self--reported. Lung function: Philips Respironics peak flow meter; PM2.5: RTI MicroPEM; CO: QRAE II multigas monitor3 months
Jary et al 27 (2014)Malawi, ruralRCT (feasibility study)Non-smoking women in Ntcheu district who cooked on traditional open wood fires, but wished to purchase a chitetezo stoveN=51; C=26; I=25Nov–Dec 2011Chitetezo stoveTraditional open wood fireIndividualExhaled CO;
cough, mucus, shortness of breath, wheezing; burning/watery eyes
PM2.5: Sidepak Monitor
CO: personal CO monitors
Symptoms were self-reported
7 days
Ludwinski et al 43 (2011)Guatemala, ruralCluster NRCT (household level)Households with open fires or stoves in poor conditionN=73 households (477 members); C=45 households (284 members); I=28 households (193 members)Aug 2008–Aug 2009Onil stoveTraditional open fireIndividualHealth outcomes (number of days having cough and eye irritation) in women and childrenHealth outcomes assessed through an interview1 year
McCracken et al 30 (2007)Guatemala, ruralRCTWomen ≥38 years living in households participating in RESPIREN=238; C=115; I=123Jul 2003–Dec 2005Plancha stoveOpen fireIndividual24-hour average PM2.5 exposureMeasured by air sampler pump3 years and 2 months
McCracken et al 28 (2009)Guatemala, ruralRCTMain study: 509 children 0–18 months
Validation study: 70 children randomly selected from main study population
Main study N=509; 1932 observations, validation study N=70; 270 observationsJan 2003–May 2004Plancha stoveOpen fireIndividual48-hour CO exposureMeasured by Gastec 1 DL passive diffusion tubes worn by the children during 48-hour periods1.5 years
McCracken et al 29 (2013)Guatemala, ruralRCTWomen ≥38 years living in households participating in RESPIREN=238; C=115; I=123Jul 2003–Dec 2005Plancha stoveOpen fireIndividual24-hour CO and PM2.5 exposurePM2.5: gravimetric measure of 24- hour personal exposure using Teflon filter
CO: span-gas calibrated passive electrochemical data logger
1 year
Mortimer et al 41 (2017)Malawi, ruralC-RCT (community level)Households with at ≥1 child aged ≤4.5 yearsN=10 750; C=5350; I=5400Dec 2013–Feb 2016Two cleaner burning biomass-fuelled cookstovesOpen firesIndividualWHO IMCI- defined pneumonia in children <5 years; WHO IMCI-defined severe pneumonia; death due to pneumoniaPneumonia: cough or difficulty breathing and fast breathing; severe pneumonia: pneumonia plus chest in-drawing, stridor or general danger sign (inability to drink or breast feed, vomiting, convulsions, lethargy or unconsciousness)2 years and 2 months
Piedrahita et al 31 (2017)Ghana, ruralC-RCT (household level)Households using biofuels as main cooking fuel sources; ≥1 child <5 years and one woman aged 18–55 yearsN=200; C=50; I=150. 50 given two locally made Gyapa rocket stoves (Gyapa/Gyapa), 50 given two Philips HD4012 LS stoves (Philips/Philips), 50 given one of each (Gyapa/Philips)Nov 2013– Jan 2016Gyapa rocket stoves, Philips HD4012 LS stovesThree-stone stovesIndividual (women and children) and kitchen48-hour carbonaceous PM2.5 exposureElemental and organic carbon in μg/m3 measured by sampling packs (backpacks for children, waist packs for adults) using quartz filters2 years
Riojas-Rodriguez et al 32 (2011)Mexico, ruralRCTSubsample of 63 women from Romieu et al (2009)33 RCTN=63 women, C=20, I=43Feb 2005–Jun 2006Patsari stoveOpen wood fireIndividual8-hour CO exposureContinuous data--logging electrochemical CO monitors10 months
Romieu et al 33 (2009)Mexico, ruralRCTHouseholds/women using open wood fire and having a child <5 yearsN=668 households, C=330, I=338Feb 2005–Jun 2006Patsari stoveOpen wood fireIndividualResp. symptoms (phlegm, cough, wheezing, chest tightness); non-resp. symptoms (eye burning, watery eyes); lung functionClinical symptoms were assessed by a team of local nurses;
spirometry was performed to determine lung function
10 months
Rosa et al 34 (2014)Rwanda, ruralC-RCT (household level)Head of household >18 years; no household members were community health workersN=566; C=281; I=285
PM2.5 was measured in
N=121; C=61; I=60
1 year and 7 monthsEcoZoom Dura stoveStone firesHousehold24-hour average PM2.5 exposurePM2.5: a semicontinuous, light scattering nephelometer (Berkeley particle and temperature sensor)5 months
Schilmann et al 35 (2015)Mexico, ruralRCTFuelwood-using households/women with child <4 years in six rural communities in Purepecha regionN=668; C=330; I=338Feb 2005– Jun 2006Patsari stoveOpen wood fireIndividualResp. infections in children <5 yearsLRI: fast breathing and cough or difficult breathing in previous 15 days and/or observed by fieldworker
URI: ≥2 of the following: cough, phlegm, nasal congestion or secretion and sore throat in previous 15 days and/or observed by fieldworker
10 months
Smith et al 36 (2010)Guatemala, ruralRCTChildren living in homes with open fires or chimney stoves in 23 villages in San Marcos highlands; children were in utero or ≤4 monthsN=534; C=265; I=269Oct 2002– Dec 2004Plancha stoveOpen fire or chimney stoveIndividual and kitchen48-hour CO exposurePersonal CO: passive diffusion GASTEC tubes
Kitchen CO: HOBO/onset CO monitor
Until child was 18 months
Smith et al 37 (2011)Guatemala, ruralRCTHouseholds with a pregnant woman or a child <4 monthsN=534; C=265; I=269Oct 2002– Dec 2004Plancha stoveOpen fireIndividualClinical, radiological or fieldworker-assessed pneumoniaFieldworker-assessed pneumonia: child with cough and/or difficulty breathing meeting criteria for referral to study physician as possible ALRIUntil child was 18 months
Smith-Sivertsen et al 38 (2009)Guatemala, ruralRCTPregnant women or families with child <4 monthsGroup A: N=300; C=147; I=153
Group B: N=204; C=98; I=106
Oct 2002– Dec 2004Plancha stoveTraditional open fireIndividual48-hour CO exposure; chronic lung symptoms (cough, phlegm, wheeze, tightness in the chest); lung functionCO: GASTEC CO passive diffusion tubes
Chronic lung symptoms assessed via questionnaire
Lung function: ATS criteria and spirometry
12 months (group A); 18 months (group B)
Thompson et al 39 (2011)Guatemala, ruralRCTHouseholds using open wood fires for cooking and having a pregnant woman or a child <4 monthsN=266; C=120; I=134Oct 2002– Dec 2004Plancha stoveOpen fireIndividual48-hour CO exposure during pregnancy;
LBW (<2500 g); birth weight
CO: passive diffusion colorimetric CO tubes;
birth weight: weighed by team staff within 48 hours after birth
Until child was born
Zhou et al 44 (2006)China, ruralCBAHouseholds that: (i) lived in the area for ≥1 year; (ii) used coal and/or biomass as main energy source; (iii) had a female member >18 years and a child <14 yearsGansu: N=1009; C=509; I=500;
Guizhou: N=1023; C=523; I=500;
Shaanxi: N=1089; C=508; I=581
March 2003– April 2005Gansu: unspecified stove;
Guizhou: air circular stove;
Shaanxi: unspecified stove
Gansu: brick/clay stove;
Guizhou: coal stove;
Shaanxi: brick/clay biomass/coal stove
Household24-hour respirable particles (RPM)
24-hour CO exposure
RPM: nylon cyclone equipped with a 37 mm diameter poly-vinyl-chloride filter
CO: long-term diffusion tubes
12 months
  • Specifications of improved cookstoves are reported in web supplementary appendix pages 15–16.

  • ALRI, acute lower respiratory tract infection; ARI, acute respiratory tract infection; ARTI, Appropriate Rural Technology Institute; ATS, American Thoracic Society; CBA, controlled before–after study; CDM, clean development mechanism; CO, carbon monoxide; C-RCT, cluster randomised controlled trial; IMCI, Integrated Management of Childhood Illness; ICS, improved cook stoves; LBW, low birth weight; LRI, lower respiratory tract infection; NRCT, non-randomised controlled trial; PEF, peak expiratory flow; PM, particulate matter; RCT, randomised controlled trial; URI, upper respiratory tract infection