Millions of older adults likely have minor memory issues that can later become dementia. But only a fraction of them are diagnosed early enough for new treatments to stand a chance.

Millions of people over the age of 65 likely have mild cognitive impairment, or MCI—minor problems with memory or decisionmaking that can, over time, turn into dementia. But a pair of recent studies both concluded that 92 percent of people experiencing MCI in the United States are not getting diagnosed at an early stage, preventing them from accessing new Alzheimer’s treatments that may be able to slow cognitive decline if it’s caught soon enough.

“We knew it was bad. But we didn’t know it was that bad,” says Ying Liu, a statistician at the University of Southern California Dornsife’s Center for Economic and Social Research and a researcher on both studies.