Kato 1990.

Study characteristics
Methods	PCC in Japan
Participants	Participants: 221 (male/female: 138/83) cases and 578 (male/female: 377/201) controls Inclusion criteria: aged ≥ 18 years, receiving a coloscopic examination at Aichi Cancer Center Hospital, Japan Recruitment: from June 1986‐March 1990
Interventions	N/A
Outcomes	Number of cases Colorectal cancer: 221 (male/female: 138/83) cases (2 cases have both colon and rectal cancer) Colon cancer: 132 (male/female: 79/53) cases Rectal cancer: 91 (male/female: 60/31) cases
Green tea in exposure categories	Exposure assessment: hot green tea Lowest exposure: < daily drinker Highest exposure: daily drinker
Notes	Funding: Grants‐in‐Aid for Cancer Research from the Ministry of Health and Welfare of Japan (61‐6 and 1‐6) Statistical methods: unconditional logistic regression Variables controlled in analysis: age, sex and residence Variables controlled by matching: age (± 5 years), sex and municipality