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Background: The burden of human papillomavirus (HPV) positive oropharyngeal squamous cell carcinoma (OPSCC) is disproportionately high among men, yet empirical evidence regarding the differential prevalence of oral HPV infection by gender is limited. Concordance of oral and genital HPV infection among men is unknown. Objective: To determine the prevalence of oral HPV infection, and concordance of oral and genital HPV infection among US men and women. Design: Nationally representative survey. Setting: Civilian noninstitutionalized population. Participants: Participants aged 18–69 years from the National Health and Nutritional Examination Survey (2011–2014). Measurements: Oral rinse, penile swab, and vaginal swab specimens were evaluated using polymerase chain reaction followed by type-specific hybridization. Results: The overall prevalence of oral HPV among men and women was 11.5% (equating to 11 million men nationwide) and 3.2% (3.2 million), respectively. High-risk oral HPV (HR-HPV) prevalence was higher among men (7.3%) than in women (1.4%). Oral HPV-16 was 6-times more common in men (1.8%) than in women (0.3%), i.e., 1.7 million men compared with 0.27 million women. Among men and women who reported having same gender sex partners, prevalence of HR-HPV infection was 12.7% and 3.6%, respectively. Particularly, among men who reported having ≥2 same gender oral sex partners, prevalence was 22.2%. Oral HPV prevalence among men with concurrent genital HPV infection was 4-fold greater (19.3%) compared to men without genital HPV infection (4.4%). Gender and lifetime number of oral sex partners were associated with overall HPV, HR-HPV, concordant overall HPV, and concordant HR-HPV infection. Limitations: Sexual behaviors were self-reported. Conclusion: Oral HPV infection is common among US men. Our findings provide several policy implications to guide future OPSCC prevention efforts to combat this disease.

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Comparison of two hazard rates is important in applications that are related to times to occurrence of a specific event. Conventional comparison procedures, such as the log-rank, Gehan-Wilcoxon and Peto-Peto tests, are powerful only when the two hazard rates do not cross each other. Because crossing hazard rates are common in practice, several procedures have been proposed in the literature for comparing such rates. However, most of these procedures consider only the alternative hypothesis with crossing hazard rates; many other realistic cases, including those when the two hazard rates run parallel to each other, are excluded from consideration. We propose a two-stage procedure that considers all possible alternatives, including ones with crossing or running parallel hazard rates. To define its significance level and "p"-value properly, a new procedure for handling the crossing hazard rates problem is suggested, which has the property that its test statistic is asymptotically independent of the test statistic of the log-rank test. We show that the two-stage procedure, with the log-rank test and the suggested procedure for handling the crossing hazard rates problem used in its two stages, performs well in applications in comparing two hazard rates. Copyright 2008 Royal Statistical Society.