When Barbara Feuerstein, seventy-two, saw a Facebook ad offering a free blood test for Alzheimer’s disease, she jumped at the opportunity. The ad, placed by a research center, offered the test, recently cleared by the Food and Drug Administration (FDA), as part of a drug study to prevent the disease. “I figured it must be safe if it was FDA approved,” said Feuerstein.

It surely helped that prominent experts had launched an impressive campaign to convince doctors, the public, and legislators to embrace widespread Alzheimer’s testing. In impassioned op-eds published around the country, Robert Redfield, former director of the Centers for Disease Control and Prevention (CDC), proclaimed, “These tests fundamentally change our understanding of the disease, just as the HIV test did for AIDS.” At senior communities and other locales across the country, mobile testing vans were offering free blood checks just outside people’s doors.

And the Alzheimer’s Association, a private institution that funds Alzheimer’s research and whose recommendations on the disease are often taken as the final word, has been promoting bipartisan legislation to ensure the test will be covered by Medicare as a screening mechanism for millions of individuals without any memory problems.