Hsu 2012.

Study characteristics
Methods	PCC in China
Participants	Participants: 371 (69.5% male) cases and 321 (69.2% male) controls. Only 317 of the 321 eligible controls) included in the analysis Inclusion criteria: aged ≤ 75 years, no previous diagnosis for nasopharyngeal carcinoma and residence in Taipei city/county, Taiwan (China) for > 6 months Recruitment: from 15 July 1991‐31 December 1994
Interventions	N/A
Outcomes	Number of cases Nasopharyngeal carcinoma: 368 cases out of 371 eligible cases
Green tea in exposure categories	Exposure assessment: intake of green tea Lowest exposure: 0 times/week Intermediate exposure: < 1 time/week Highest exposure: ≥ 1 time/week
Notes	Funding: National Institutes of Health, USAA Statistical methods: unconditional logistic regression Variables controlled in analysis: age, sex, ethnicity, educational level, nasopharyngeal carcinoma family history, total calories intake, years of cigarette smoking and exposure to formaldehyde and wood dust Variables controlled by matching: ‐