The new analysis doesn’t resolve the dilemmas surrounding choices about prostate cancer screening. While prostate cancer is one of the most common cancers affecting men and it can be aggressive, many men have a slow-growing form of the disease that will likely never become life-threatening, and would not even know about it if not for screening.

More patients with these low-grade cancers are now being closely monitored by doctors instead of undergoing surgery and radiation, treatments that can lead to serious complications such as incontinence and impotence.

The aim of monitoring, or active surveillance as it is called, is to prevent unneeded treatment, said Dr. Etzioni, who does research on the harms of screening as well. “On average, in the screened population, more men will be over-treated than have their lives saved,” Dr. Etzioni said.

In its most recent draft of recommendations issued in April, the United States Preventive Services Task Force urged older men to talk to their doctors about the benefits and risks of prostate cancer screening and make an individual decision that is right for them. That’s a change from the earlier guideline issued in 2012, which told men who were not at increased risk to skip routine screenings altogether. The task force could massage the recommendation further over the next few months before issuing a final version.

Andrew J. Vickers, an attending research methodologist at Memorial Sloan Kettering Cancer Center, who wrote an editorial accompanying the new paper, said in an interview that there really is no doubt that PSA screening can curb the death rate from prostate cancer. “The debate shouldn’t be to screen or not to screen, but how can we change screening so it does not cause harm,” Dr. Vickers said.

“It’s not a take-it-or-leave-it,” Dr. Vickers said. “A PSA test cannot really harm you or save your life. What can harm you is if the test leads you to get treatment you don’t need, and what can save your life is the PSA test that finds the cancer that could kill you.”

Critics of screening say the new analysis does not change much in the calculation of risks versus benefits of screening. Only 3 percent of men die of prostate cancer, so the benefit of screening, in the number of prostate cancer deaths averted, is small in absolute terms.