All type of patients: 7 trials - WACS beta-caroten - NSCP (Green) beta carotene - WHS beta carotene - CARET beta carotene - PHS beta carotene - ATBC beta carotene - SCP beta carotene
Primary prevention: 4 trials - WHS beta carotene - CARET beta carotene - PHS beta carotene - ATBC beta carotene
Secondary prevention: 2 trials - WACS beta-caroten - ATBC 2nd prev subgroup (b carotene)