The National Conference of Catholic Bishops yesterday elected a scholar and theologian, Archbishop John R. Quinn, 48, of San Fancisco, as its president for the next three years.

He succeeds Archbishop Joseph L. Bernardin in the post, which makes him chief spokesman for the American Roman Catholic Church.

Quinn was chosen on the third ballot from a slate of 10. The runner-up, Archbishop John R. Roach of St. Paul-Minnespolis, was named vice president.

Quinn does not fit nearly into either the progressive or the conservative characterizations of a Catholic leader. He is a strict constructionist on church law, but at the same time is attuned to the church's human dimension. He was one of the key participants in a successful battle to keep conservative elements in the hierarchy from scuttling the findings of last year's Call to Action Conference, which examined social concerns for the church.

In business sessions that proceeded around the balloting yesterday morning, Bishop Michael F. McAuliffe of Jefferson City, Mo., reported on a study of the extent to which women are used in decision-making positions in local dioceses.

McAuliffe said the survey showed that the largest number were in education (22 per cent) and social service work (16 per cent). Other areas employing women in decision-making positions ranged from 8 per cent in communications to 2 per cent in seminary training.

He said the bishop's conference's committee on women in society and the church was encouraged by the survey findings because they indicated that "women are becoming more involved in decision-making positions within the church at the diocesan level."

The committee's next step, he said, is "a study to determine how women are involved in the life and ministries of the parish - how women are involved in decisions that affect parish life" and "how women are accepted in such roles by both priests and parishioners."

He expressed hope the survey would encourage the bishops to "open up new avenues for applying the talents of women to the service of the church . . . It is certain that the church will benefit if decision-making positions can be appropriately matched with the unique capacities that the (Holy) Spirit has given to women and if the range ministerial possibilities for women is brought to the attention" of leaders of the church.

Terence Cardinal Cooke of New York, the bishops' chairman for anti-abortion activities, reported that the church's efforts in that field produce "a greater impact each year."

He said that "pro-abortion forces are working diligently; the public debate is sometimes harsh" and couched in rhetoric that tends to "stir up intent anti-Catholic sentiments."

Despite these attacks, he said, the hierarchy is convinced "we must speak out for the unborn" and work for a constitutional amendment to outlaw abortions.

Cooke said his committee also is working "to develop a family planning program for teenagers" using "natural" techniques. He said the program, which would be financed by public funds, would "counter programs promoting contraceptives," which the church has forbidden.

Roach reported that a special committee he heads is developing a five-year agenda of social concerns for the church based on proposals that came out of the broadly representative Call to Action Conference in Detroit.

That conference, the culmination of a two-year process of consultations with grass-roots Catholics around the country, produced 182 recommendations for action in several areas.

Bishop James S. Rausch of Phoenix praised a similar consultative process last summer that focussed on Spanish-speaking Catholics. He said the Hispanic gathering "signaled a change" in the Hispanics' view of church, from a church that is silent to one that speaks; from a church of the masses to one that is made up of basic Christian communities."