Angelina Jolie
Her 2013 New York Times essay about carrying a BRCA1 mutation and choosing preventive mastectomy roughly doubled referrals for hereditary cancer testing in several countries: the "Angelina Jolie effect".
Angelina Jolie's mother, Marcheline Bertrand, died of ovarian cancer in 2007 at 56. In May 2013 Jolie wrote in The New York Times that she carried a BRCA1 mutation, that her doctors estimated a high lifetime risk of breast and ovarian cancer, and that she had chosen a preventive double mastectomy. In 2015 she wrote a second essay about removing her ovaries and fallopian tubes. Published studies in the UK, US, Canada and Australia recorded a sharp and sustained rise in referrals for genetic counselling and BRCA testing after the first essay, with no fall in the proportion of tests that were appropriate. Her essays are the clearest documented example of a single public disclosure changing uptake of a preventive medical service.