Two social policy analysts told a House committee yesterday that the increase of black single-parent families has done less to increase poverty rates among black Americans than many experts have suggested.

Speaking at a hearing on "Hunger, Poverty and the Black Family," held as part of the Congressional Black Caucus Weekend, Mary Jo Bane of the New York State Department of Social Service and Marilyn Moon of the Urban Institute, said the assumption that the rise in single-parent black families has caused more black poverty is wrong.

"People sometimes seem to conclude . . . that the poverty problem could be solved if only ways could be found to encourage more stable black marriages and to deter births to unmarried black mothers," Bane said, adding that the facts "are a little more complicated."

Bane said the changing family structure among blacks did have some impact on the poverty rate. She said that family changes "contributed almost nothing" to the sharp increase in poverty among blacks that occurred between 1979 and 1983. And, she said, if family composition among blacks in 1979 had been the same as in 1960, the overall poverty rate among blacks would have been 24 percent rather than 31 percent .

Bane said the assumption that black family breakup was causing poverty took hold during the 1960s and 1970s when poverty rates were dropping faster for blacks in two-parent families than those in single parent families. But she said poverty may have caused families to break up.

"What had originally looked like an effect of family-structure change on poverty might instead have been an effect of poverty on family structures," she told Rep. Mickey Leland (D-Tex.), who chaired the hearing and also chairs the black caucus.

She added that a separate study showed that two-thirds of blacks who became poor after a family breakup were poor before. The results for whites were sharply different. Three-quarters of whites who became poor after a family breakup were not previously impoverished.

She noted that when poor families experience a divorce, there is an increase in "poor, female-headed households but no increase in the number of people who are poor."

Similarly, Bane said, when a poor woman has a child outside of marriage the single parent family created by the birth is not a spur to increased poverty but a reflection of existing poverty.

The New York state official's conclusions were supported by Moon of the Urban Institute: "If black families and individuals are separated into groups such as female-headed families or two-earner families to control for differences in family composition, they [blacks] still began the decade with lower incomes and lost ground to white families in terms of income growth," she said.