The Trump administration has abruptly halted work on a highly regarded program to help physicians, families, state and local government agencies, and others separate effective “evidence-based” treatments for substance abuse and behavioral health problems from worthless interventions.

The program, called the National Registry of Evidence-Based Programs and Practices, was launched in 1997 and is run by the Substance Abuse and Mental Health Services Administration. Its website lists 453 programs in behavioral health — aimed at everything from addiction and parenting to HIV prevention, teen depression, and suicide-hotline training — that have been shown, by rigorous outcomes measures, to be effective and not quackery. The most recent were added last September.