Shrinking Samples, Expanding Claims: The Quiet Crisis of Attrition in America's Longitudinal Surveys
Participation rates in the United States' most influential longitudinal surveys have been declining for decades, and the people who remain in these studies are increasingly unlike those who dropped out. The result is a compounding distortion that widens with every successive wave — yet the research claims built on this eroding foundation rarely acknowledge how much the ground has shifted beneath them.