A diversity panel appointed by Mayor Bill de Blasio has called for New York City to stop using academic criteria to screen applicants for admission to public middle schools, and to phase out elementary gifted-and-talented programs that now require a test.

If approved, the changes would mark major shifts for the nation’s largest school district, which a study called one of the most segregated urban systems in the country.

Mr. de Blasio has promised to make New York the fairest big city in America. But so far, he hasn’t made sweeping changes to a complex system of choice, in which many schools rank applicants by factors such as state test scores, course grades and attendance.

Some parents and educators say screened admissions unfairly block many talented low-income, black and Hispanic students from desirable schools and gifted programs. The screening process grew partly as a way to keep wealthier families in public education, with high-achieving middle and high schools offering spots to students with strong academic records.

The School Diversity Advisory Group, convened in 2017 to produce recommendations, has more than 40 members representing civil-rights organizations, unions, students, the city Department of Education and others. It includes mayoral allies: one of its leaders is his former counsel, Maya Wiley. It will hold a news conference on Tuesday to discuss its recommendations.