Yesterday I wrote my first post on Tom Baker's book The Medical Malpratice Myth. I talked about how the number of people injured every year is drastically larger than those who bring suits, as well as the fact that all malpractice spending (premiums, legal representation, awards, etc) amounts to less than one half of one percent of all health care spending.
A commentor was keen to pick up on another malpractice talking point -- the notion of "defensive medicine". So where does defensive medicine fit in the malpractice spending puzzle?
As far as we can tell, "defensive medicine" is one of those tiny puzzle pieces with the really strange shape (you know, the one that seems to have 2.5 sides?) -- you can't figure out where it goes until you've trudged your way through the majority of the puzzle.
That's because defensive medicine is notoriously difficult to study. First, researchers have to decide what constitutes defensive medicine. Then they have to tease out whether the effects of those actions were harmful or helpful. Given the fact that 100,000 people die per year because of medical error, some instances of defensive medicine will be helpful because they'll help reduce that number. Others will simply be unnecessary tests or more invasive procedures to ensure "certainty", leading to increased spending and even more risk.
The research that has been conducted indicates, for the most part, that defensive medicine has little effect overall and that states with tort reform have slightly lower rates of spending than those without. But one thing is clear -- malpractice fears aren't sending shock waves through the system.
• In a clinic scenario survey by the Office of Technology Assessment, where doctors were given a situation and asked how they would proceed, researchers calculated that 95% of doctors did nothing but order a test or diagnostic procedure. The principle reason doctors gave for ordering the procedure "almost all of the time" was medical indications. "Malpractice concerns" were given as a reason in less than one half of one percent of the cases. OTA researchers concluded defensive medicine is "not likely to explain very much of the huge growth in health-care expenses over the last century".
• Researchers at Syracuse examined birth records and compared cesarean delivery rates according to the number of malpractice cases per county. They found that in places with a higher malpractice risk that there was actually a slight decrease in c-sections.
• Harvard researchers compared cesarean rates to the actual hospital rates of malpractice suits and found that, controlling for all other factors, a woman who gave birth at a hospital with high malpractice rates was 30% more likely to have a c-section. Except researchers also found that giving birth at a hospital with a high c-section rate (and not necessarily malpractice rate) increased the risk of having a c-section 10 times.
• Mark McClellan (current secretary of CMS) found that heart disease expenses for the elderly grew only 5-7% less in state with tort reform (expenses grew 24% per year in non-reform states, and 17% in reform states) , and that the gains seemed to decrease after 5 years.
This research shows that, when researchers have been able to puzzle out ways to measure it, they found very small rates of increased spending and intervention due to "defensive medicine".
The bottom line is that while the evidence isn't crystal clear that defensive medicine plays no part, there's nothing that shows defensive medicine is dictating doctors' behavior. More contemporary research needs to be done (the majority of these projects were in the late 1980's and early 1990's), but there's no indication of a rash of doctors performing unnecessary procedures and tests because of their fear of frivolous lawsuits.