Table 3.

Predictive model for influenza constructed using multivariable logistic regression among patients enrolled with influenza-like illness (ILI) in southern Sri Lanka, March–November 2013 (odds ratios [OR] with 95% confidence intervals [CI] and P values)^*

	Full model		Reduced model
	OR (95% CI)	P value	OR (95% CI)	P value
Children
Age of child, categorized	2.02 (1.27–3.22)	0.003	2.26 (1.49–3.43)	< 0.001
Pain with breathing	8.55 (1.04–70.2)	0.05	8.90 (1.08–73.0)	0.04
Headache	1.28 (0.52–3.11)	0.59	−	−
Fatigue	2.23 (0.89–5.60)	0.09	−	−
Myalgias	1.04 (0.47–2.28)	0.93	−	−
Adults
Sick contact	3.23 (1.51–6.89)	0.002	3.62 (1.73–7.59)	0.001
Pain with breathing	1.92 (0.83–4.42)	0.126	−	−
Vomiting	2.38 (0.68–8.39)	0.18	−	−
Arthralgias	3.96 (0.95–16.4)	0.06	4.93 (1.23–19.7)	0.02

CI = confidence intervals; OR = odds ratio.

^*P values listed in bold are significant at < 0.05.