Primary outcomes of included (quasi-)experimental studies
| First author (year) | Events | Effect measures | Summary of findings | |
| Intervention | Control | OR/RR (95% CI) | ||
| Pregnancy and infant outcomes | ||||
| Low birth weight (LBW) | ||||
| Thompson et al (2011)39 | n/N (%): 13/69 (19%) | n/N (%): 26/105 (25%) | OR (95% CI): 0.74 (0.33, 1.66) | There was no statistically significant difference in LBW between infants born to mothers using wood-fuelled chimney stoves and those born to mothers using open fires |
| Infant mortality, stillbirths and miscarriages* | ||||
| Hanna et al (2012)26 | 14.7% (n/N not reported) | 11.9% (n/N not reported) | Relative risk change (95% CI): 15% (–13, 43) | The study found no effect of randomly being offered a stove on infant mortality, stillbirths and miscarriages |
| Children | ||||
| Acute respiratory infections (including pneumonia) | ||||
| Hartinger et al (2016)40 | N=248 Number of ARI episodes: 831 Number of ALRI episodes: 25/554 (554 ARI episodes seen with respiratory rate measurements) | N=251 Number of ARI episodes: 877 Total number of ALRI episodes: 10/563 (563 ARI episodes seen with respiratory rate measurements) | Number of ARI episodes Relative rate (95% CI): 0.95 (0.82, 1.10) Number of ALRI episodes Relative rate (95% CI): 2.47 (0.84, 7.29) | The study did not observe a reduction in paediatric ARI and ALRI episodes among improved stove users |
| Mortimer et al (2017)41 | Number of IMCI-defined pneumonia episodes in the overall intention-to-treat population: 1255/5297 Incidence rate (cases per 100 child-years) (95% CI): 15.76 (14.89, 16.63) Number of IMCI-defined severe pneumonia episodes in the overall intention-to-treat population: 186/5297 Incidence rate (cases per 100 child-years) (95% CI): 2.33 (2.00, 2.67) | Number of IMCI-defined pneumonia episodes in the overall intention-to-treat population: 1251/5246 Incidence rate (cases per 100 child-years) (95% CI): 15.58 (14.72, 16.45) Number of IMCI-defined severe pneumonia episodes in the overall intention-to-treat population: 145/5246 Incidence rate (cases per 100 child-years) (95% CI): 1.80 (1.51, 2.09) | IMCI-defined pneumonia IRR (95% CI): 1.05 (0.93, 1.18) IMCI-defined severe pneumonia IRR (95% CI): 1.30 (0.99, 1.71) | The study found no evidence that an intervention comprising cleaner burning biomass-fuelled cookstoves reduced the risk of pneumonia in young children |
| Schilmann et al (2015)35 | N=287 (prevalence not reported) | N=272 (prevalence not reported) | URI: using mainly Patsari stove: OR (95% CI): 0.84 (0.69, 1.03) Combined use of Patsari and traditional stoves: OR (95% CI): 0.93 (0.76, 1.18) LRI: using mainly Patsari stove: OR (95% CI): 0.61 (0.21, 1.81) Combined use of Patsari and traditional stoves: OR (95% CI): 0.88 (0.26, 2.99) | There was no significant impact on the incidence of respiratory infections among children of mothers using mainly the Patsari stove. There was, however, a reduction in the duration of both URIs and LRIs in Patsari users (IRR (95% CI): 0.79 (0.70, 0.89) and 0.41 (0.21, 0.80), respectively) |
| Smith et al (2011)37 | N=265 Clinical pneumonia: 124/15 526 child weeks† 60/15 553 child weeks‡ Radiological pneumonia: 41/15 558 child weeks† 25/15 559 child weeks‡ RSV negative: 73/15 542 child weeks† 27/15 564 child weeks‡ RSV positive: 43/15 556 child weeks† 30/15 568 child weeks‡ Fieldworker-assessed pneumonia: 321/14 379 child weeks† 26/14 719 child weeks‡ | N=253 Clinical pneumonia: 139/14 871 child weeks† 76/14 891 child weeks‡ Radiological pneumonia: 44/14 886 child weeks† 28/14 891 child weeks‡ RSV negative: 77/14 877 child weeks† 42/14 899 child weeks‡ RSV positive: 43/14 879 child weeks† 27/14 897 child weeks‡ Fieldworker-assessed pneumonia: 340/13 939 child weeks† 45/14 310 child weeks‡ |
Clinical pneumonia: IRR (95% CI): 0.78 (0.59, 1.06)† IRR (95% CI): 0.67 (0.45, 0.98)‡ Radiological pneumonia: IRR (95% CI): 0.74 (0.42, 1.15)† IRR (95% CI): 0.68 (0.36, 1.33)‡ RSV negative: IRR (95% CI): 0.79 (0.53 to 1.07)† IRR (95% CI): 0.54 (0.31 to 0.91)‡ RSV positive: IRR (95% CI): 0.76 (0.42 to 1.16)† IRR (95% CI): 0.87 (0.46 to 1.51)‡ Fieldworker-assessed pneumonia: IRR (95% CI): 0.91 (0.74, 1.13)† IRR (95% CI): 0.56 (0.32, 0.97)‡ | Implementation of chimney stoves did not significantly impact the incidence of physician-diagnosed pneumonia (any severity) for children younger than 18 months. There were, however, significant reductions in the intervention group for severe fieldworker-assessed, physician-diagnosed and RSV-negative pneumonia |
*Broader definition than the one prespecified (perinatal mortality) in the protocol.
†All cases of pneumonia.
‡Severe cases of pneumonia.
ALRI, acute lower respiratory tract infection; ARI, acute respiratory tract infection; IMCI, integrated management of illness; IRR, incidence rate ratio; LRI, lower respiratory infection; RR, risk ratio; RSV, respiratory syncytial virus; URI, upper respiratoy infection.