 The researchers used data from a study that's followed nearly 5,000 children in the U.S. since their birth over 20 years ago. About 46% of the children had stable housing throughout this time. A similar number had low levels of intermittent housing insecurity. And about 6% had high levels of housing insecurity in early childhood. Study author Kristen Pierce is at NYU Grossman School of Medicine. That children who experience any level of housing insecurity, they had worse health outcomes at age 15.