Table 4.

Univariate and multivariate survival analyses of time to first event for different otitis outcomes, hazard ratios and 95% confidence intervals

Variable/s included in analyses	OME	AOM	TMP	CSOM
	Hazard ratio (95% CI)	Hazard ratio (95% CI)	Hazard ratio (95% CI)	Hazard ratio (95% CI)
Univariate
Vaccinated versus comparison group	1.17 (0.85 – 1.62)	0.80 (0.51 – 1.26)	0.84 (0.42 – 1.67)	0.57 (0.20 – 1.62)
Age at first examination (days)	0.98 (0.98 – 0.99)	1.00 (0.99 – 1.01)	n/a	n/a
Females/Males	0.79 (0.57 – 1.10)	1.06 (0.70 – 1.60)	0.99 (0.53 – 1.88)	0.36 (0.11 – 1.13)
Rate of non-respiratory illness*	1.09 (0.79 – 1.52)	1.08 (0.73 – 1.60)	1.07 (0.57 – 2.01)	0.98 (0.39 – 2.46)
Rate of prior antibiotic prescription*	0.71 (0.48 – 1.03)	0.91 (0.62 – 1.35)	0.95 (0.53 – 1.72)	1.63 (0.75 – 3.58)
Birth weight (kg)	0.99 (0.74 – 1.33)	1.04 (0.71 – 1.54)	0.90 (0.49 – 1.66)	0.94 (0.35 – 2.54)
Rate of well clinic visits*	1.10 (0.99 – 1.23)	1.32 (1.07 – 1.62)	1.09 (0.74 – 1.62)	1.10 (0.57 – 2.12)
Late immunisation	0.64 (0.36 – 1.17)	0.69 (0.39 – 1.22)	0.66 (0.31 – 1.40)	1.19 (0.40 – 3.54)
Multivariate
Vaccinated versus comparison group	0.90 (0.64 – 1.25)	1.01 (0.61 – 1.67)	0.83 (0.41 – 1.66)	0.56 (0.19 – 1.62)
Age at first examination (days)	0.98 (0.97 – 0.99)	n/a	n/a	n/a
Rate of non-respiratory illness*	1.14 (0.83 – 1.56)	1.04 (0.71 – 1.52)	1.09 (0.58 – 2.07)	1.04 (0.42 – 2.60)
Rate of well clinic visits*	n/a	1.32 (1.05 – 1.65)	n/a	n/a

Note: 150 episodes of first OME in 160 participants, 91 episodes of first AOM in 127 participants, 38 episodes of first TMP in 135 participants, 15 episodes of first CSOM in 145 participants.

* (per month).

n/a not applicable.