Doctors praised the study results.

“I’m very favorably impressed they were able to pull this study off so successfully, and it clearly shows the importance of early intervention,” said Dr. William T. Carpenter, a professor of psychiatry at the University of Maryland School of Medicine, who was not involved in the study.

Dr. Mary E. Olson, an assistant professor of psychiatry at the University of Massachusetts Medical School, who has worked to promote approaches to psychosis that are less reliant on drugs, said the combined treatment had a lot in common with Open Dialogue, a Finnish program developed in the 1980s. “These are zeitgeist ideas, and I think it’s thrilling that this trial got such good results,” Dr. Olson said.

In the new study, doctors used the medications as part of a package of treatments and worked to keep the doses as low as possible minimizing their bad effects. The sprawling research team, led by Dr. John M. Kane, chairman of the psychiatry department at Hofstra North Shore-LIJ School of Medicine, randomly assigned 34 community care clinics in 21 states to provide either treatment as usual, or the combined package.

The team trained staff members at the selected clinics to deliver that package, and it included three elements in addition to the medication. First, help with work or school such as assistance in deciding which classes or opportunities are most appropriate, given a person’s symptoms. Second, education for family members to increase their understanding of the disorder. And finally, one-on-one talk therapy in which the person with the diagnosis learns tools to build social relationships, reduce substance use and help manage the symptoms, which include mood problems as well as hallucinations and delusions.

For example, some patients can learn to defuse the voices in their head — depending on the severity of the episode — by ignoring them or talking back. The team recruited 404 people with first-episode psychosis, mostly diagnosed in their late teens or 20s. About half got the combined approach and half received treatment as usual. Clinicians monitored both groups using standardized checklists that rate symptom severity and quality of life, like whether a person is working, and how well he or she is getting along with family members.

The group that started on the combined treatment scored, on average, more poorly on both measures at the beginning of the trial. Over two years, both groups showed steady improvement. But by the end, those who had been in the combined program had more symptom relief, and were functioning better as well.The researchers expect to have lowered average doses in the combined program but had not yet finished analyzing that data.