Continuing coverage: UTMB’s Jacques Baillargeon had a hunch that prescriptions for testosterone therapy were on the rise just from watching ads on ESPN and other television networks. So Baillargeon checked the medical literature and pharmaceutical sales data. Sure enough, testosterone prescriptions and drug sales were spiking. To see who was taking the hormone, he assembled a team to study a decade's worth of insurance claims from 10 million men, 40 years old and older.