The U.S. medical malpractice system is broken. It frequently does not punish doctors who need punishing, while levying fines against doctors who did nothing wrong. And this dreadfully inaccurate system still manages to take almost five years, on average, to settle claims.

Experts have been promoting a type of reform known as safe harbor rules, which would shield physicians from lawsuits in cases where they were known to be following accepted clinical guidelines. For example, a patient who develops metastatic prostate cancer could not sue his physician for failing to screen him for that cancer if safe harbor rules include recent guidelines concluding the prostate screening is not routinely indicated.

The goal of safe harbor rules is to protect doctors from frivolous lawsuits. A study suggests the rule will probably be more beneficial to patients than doctors. The researchers reviewed over 900 malpractice lawsuits in Oregon that took place between 2002 and 2009. They reviewed the claims and tried to figure out if those cases would have gone differently if Oregon had a safe harbor rule in place at that time. They found that only 3 of 970 claims decided against doctors would have instead been decided in their favor if a safe harbor rule had been in place. In other words, safe harbor legislation does not look like it will help doctors very much. Worse yet for doctors, 14 cases would have likely been decided against them, because of harms that were caused by physicians not following practice guidelines.

But the point of malpractice reform is not simply to relieve physicians of unwarranted lawsuits. The most important goal is to improve the quality of care that physicians provide. The research team discovered 41 cases in which patients would not have been harmed if physicians had followed practice guidelines. See the accompanying table, which summarizes their findings:

In short, safe harbor legislation will not necessarily reduce the number of medical malpractice suits in the U.S. But it might improve patient care, by focusing physicians on the importance of following carefully crafted clinical guidelines.

Peter Ubel is a physician and behavioral scientist who blogs at his self-titled site, Peter Ubel and can be reached on Twitter @PeterUbel.  He is the author of Critical Decisions: How You and Your Doctor Can Make the Right Medical Choices Together. This article originally appeared in Forbes.