Table 4. Significant results from a multivariate Poisson regression model assessing potential risk factors for pneumonia.

Risk factor	IRR	95% CI	p-value
First episode of pneumonia a
Maternal age <18 years	1.59	1.12–2.27	0.01
House volume per person (m3)	0.99	0.99–1.00	0.03
Number of rooms	0.85	0.77–0.95	0.004
Multiple episodes of pneumonia b
Distance to next house	0.86	0.74–1.00	0.04
Primary endpoint pneumonia c
Distance stove to bed	0.89	0.80–0.99	0.03

In addition to the factors in the table, the multivariate model included all factors from Table 1 which were significant in univariate analysis. The following were non-significant:

^adistance from the household stove to the infants sleeping area.

^bseason of birth.

^cbirth weight and the number of people sleeping in the same bed as the infant.