Table 4. Univariable and multivariable analysis of putative risk factors associated with having an HPV positive tumour.

Variable		Univariable analysis			Multivariable analysis
		Odds Ratio	95% CI	P value	Odds Ratio	95% CI	P value
Age	≤60	REF1			REF1
	≥61	0.48	0.28–0.82	<0.01	0.55	0.33–0.99	0.05
Sex	Female	REF1			REF1
	Male	1.50	0.79–2.78	0.21	1.36	0.68–2.66	0.38
Ethnicity	NZ European	REF1			REF1
	NZ Māori	1.82	0.74–5.15	0.22	1.49	0.55–4.52	0.45
	Other	1.07	0.52–2.27	0.86	1.14	0.53–2.53	0.74
Timeframe	1996–98	REF1			REF1
	2003–05	1.75	0.84–3.67	0.14	1.76	0.83–3.81	0.14
	2010–12	5.90	2.82–12.62	<0.01	5.65	2.60–12.30	<0.01

¹ REF is the baseline level (OR = 1.00)