A survey by a national Catholic journal of practices and attitudes in the more than 18,000 Roman Catholic parishes across the country has confirmed that lay Catholics are playing increasingly key roles in church affairs.

Results of the study are included in the April issue of the U.S. Catholic, a monthly magazine edited for popular readership by the Claretian Fathers and Brothers in Chicago.

About 300 parishes participated in the survey. One-fifth of the respondents represented suburban churches; the remainder were divided evenly between city and rural areas.

The survey which covered a wide range of practices in local churches, indicated that 63 percent of the parishes surveyed use lay ministers of communion - lay persons trained to assist the priest in distributing communion to the worshippers. Women serve in this capacity in 47 percent of the parishes.

Twenty-three percent of the parishes surveyed employ lay persons as part of the pastoral ministry of the church. Substantially larger numbers of lay persons are involved as volunteers in such activities as parish visitors to hospitals and nursing homes (70 percent of the parishes) visitation programs for senior citizens (41 percent) and organized programs of meals for senior citizens (22 per cent).

Four of every five parishes have pastoral councils, an important means for involving lay persons in parish affairs.

"The women's role in the parish is growing, but not as fast as the layman's," the magazine observed. The study found that 86 percent of the parishes have women lectors at mass, but only 12 percent have women servers assisting the priest at mass.

The study of the parishes reflected both the struggle to implement the reforms of the Second Vatican Council and a faithfulness to traditional practices of the faith.

A guitar or folk choir could be found in 58 percent of the parishes and 80 percent have set aside and furnished a special room for the new rite of reconciliation.

This new rite, introduced two years ago, has replaced the traditional dark and quasianonymous confessional with more conversational, face-to-face encounter between priest and penitent.

The Latin mass is celebrated "occosionally" in 12 jercent of the parishes. The study does not indicate whether it is the outlawed Tridentine mass or the authorized new version. In 31 percent of the parishes, people gather weekly to recite the rosary as a group; 59 percent of the parishes studied hold a ceremonial crowning of the Virgin Mother every May.