JACKSON (AP) — Mississippi settled a lawsuit this week and agreed to improve its foster care system, but an advocate says it could be a while before children in the program start to see changes.

‘‘Mississippi has been operating at such a low level for such a long time and needs to make so many changes in terms of structural reform, that it’s hard to know when we will start seeing better outcomes for children,’’ Marcia Robinson Lowry, founder and executive director of Children’s Rights, said Thursday in a telephone interview from New York.

Children’s Rights is a national advocacy group that sued Mississippi in 2004 to push for better conditions for the estimated 3,000 to 3,500 children in foster care.

The lawsuit settlement was signed Wednesday and announced Thursday. Attorneys will present the settlement to a federal judge Jan. 4 for final approval, and the state will have five years to put changes in place.

Under the settlement:

4The state Department of Human Services will hire more social workers and increase the number of visits the workers make to each foster child.

4DHS will increase its offerings of educational and therapeutic services for foster parents and children.

4 The state will do a more thorough job of checking children’s physical and mental health when they enter foster care.

4The state will establish a 24-hour hot line so people can report abuse or mistreatment of children throughout the state.

4 The state will increase reimbursement rates for foster parents.

4 DHS will have to be approved by the Council on Accreditation, a national group that helps states improve their foster care systems.

U.S. District Judge Tom Lee approved a partial settlement of the Mississippi case in April.

At the time, attorneys from both sides agreed to work together on a plan to improve conditions for children.

‘‘Foster care is a challenge for every state because of the complexities involved in caring for these most vulnerable children,’’ Gov. Haley Barbour said in a news release Thursday. ‘‘Since only a handful of states are accredited in this area, I expect this settlement to help create a system in Mississippi that will become a national model for how these essential services can best be delivered.’’

State Attorney General Jim Hood, whose office represented the state in the case, said: ‘‘It will require a great deal of hard work on the part of Human Services to fulfill the terms of this agreement.’’

Lowry said Mississippi probably will have to spend millions of dollars to meet the mandates of the settlement.

‘‘It is going to cost them money,’’ Lowry said. ‘‘On the other hand, the state has been squandering the lives of children, so it’s a question of where you want to put your resources.’’

She said the state has missed the chance to apply for federal money that could pay for some of the required changes.