Bulletin of the World Health Organization

Indoor air pollution from unprocessed solid fuel use and pneumonia risk in children aged under five years: a systematic review and meta-analysis

Mukesh Dherani, Daniel Pope, Maya Mascarenhas, Kirk R Smith, Martin Weber, Nigel Bruce

Volume 86, Number 5, May 2008, 390-398

Table 3. Pooled odds ratios from meta-analysis of all studies and sensitivity analyses

Group	Detail	Estimates including low exposure prevalence studies			Estimates excluding low exposure prevalence studies
Group	Detail	N	OR	95% CI	N	OR	95% CI
All studies		27	1.78	1.45–2.18	23	1.93	1.54–2.42
All studies		26	1.67^a	1.39–2.01	22	1.79^a	1.46–2.21
Study design	Randomized control trial (one study)	2	1.28	1.06–1.54	No studies with low prevalence
	Cohort	7	2.12	1.05–4.25	No studies with low prevalence
	All case–control	15	1.97	1.47–2.64	11	2.38	1.90–2.97
	Case–control with good control selection	(9)	1.50	1.05–2.14	(5)	2.17	1.07–4.41
	Cross sectional	3	1.49	1.21–1.85	No studies with low prevalence
Confounding	Adequate or good adjustment^a	16	1.77	1.43–2.18	14	1.80	1.43–2.25
Exposure	Good categorization^a	16	1.67	1.33–2.09	14	1.73	1.35–2.20
Exposure	Solid versus clean fuel^a	14	1.69	1.29–2.20	12	1.76	1.32–2.36
Outcome	Excluding DHS^a	23	1.72	1.37–2.17	19	1.89	1.44–2.48
measure	Used physician diagnosis or more specific	20	1.65	1.26–2.15	16	1.83	1.31–2.55
measure	Used physician diagnosis or more specific	–	–	–	15	1.97^b	1.44–2.70
Age group	< 60 months	11	1.62	1.21–2.15	10	1.67	1.22–2.30
	< 36 months	4	2.05	1.38–3.07	3	2.17	1.37–3.43
	< 24 months^a	12	1.96	1.36–2.82	9	1.85	1.27–2.69

CI, confidence interval; DHS, Demographic and Health Surveys; OR, odds ratio.^a Exclusion of Group II in study by Pandey et al.³² (this study was of children < 24 months of age, so only required exclusion in the youngest group in the age sensitivity analyses).^b Exclusion of study by Jin et al.³⁵