Fig 1. Incidence of oropharyngeal and non-oropharyngeal head and neck squamous cell carcinomas in Singapore 1968–2012, by gender.

Incidence trends are based on incidence rates for 5-year time periods that were age-adjusted to the WHO standard population. Annual percent change (APC) was calculated using Joinpoint regression analysis. APC = annual percent change. An asterisk (*) indicates an APC value that is statistically significant at p≤0.05. Abbreviations: OPSCC = oropharyngeal squamous cell carcinoma; non-OP HNC = non-oropharyngeal head and neck squamous cell carcinoma