With critics questioning whether regulators give medical devices enough scrutiny before approving them for patients, University of Minnesota law Prof. Ralph Hall pored over seemingly obscure regulatory data to determine whether the allegations are true.

Hall studied Food and Drug Administration (FDA) recalls of medical devices between 2005 and 2009, focusing on the most-serious kind of pullback -- products that could cause serious injury or death in patients if they malfunctioned. There were 112 recalls in that category.

Of those, roughly 55 percent were recalled because of "post-market" issues, mostly manufacturing problems, and 45 percent were traced to "pre-market" issues -- mostly design and software design problems.

Hall's conclusion: More clinical studies testing medical devices in humans probably wouldn't have prevented the pre-market problems behind most serious recalls. Instead, more bench testing and stricter design controls would "appear to be more effective and more ethical," he said in a presentation Tuesday sponsored by the industry group LifeScience Alley.

But as the FDA revamps the way most medical devices are cleared for use, regulators may require manufacturers to invest in more clinical studies to prove their products are safe.

Effect on Minnesota

This is especially controversial in Minnesota -- home to Medtronic Inc., the world's largest medical technology company, and several hundred other med-tech firms -- because clinical studies cost millions of dollars and prolong the approval process.

The FDA has trained its eye on revamping the 510(k) approval process -- which requires medical device makers to prove a product is similar to one already on the market before launching it commercially, and sometimes without first testing the product on humans. The agency released its preliminary recommendations last week.

Meanwhile, the Institute of Medicine, an independent entity that provides advice to policymakers, will release a report next summer with its suggestions for changes.

Although Hall recently presented his findings to the institute, he's concerned that regulators have a "ready, fire, aim" strategy.

"They're making changes but don't know what the problem is," he said.

Hall found in his study that 89 recalled products were cleared through the 510(k) process in the five-year period-- less than 1 percent of the total number of products submitted for clearance.

Based on his recall data, Hall says the FDA has an excellent safety record. (The study was funded by a grant from the Kauffman Foundation, with support from the U's Law School.)

Don Gerhardt, CEO of LifeScience Alley, estimates that 55 percent of all the med-tech and life science companies in Minnesota are entirely dependent on selling 510(k)-approved products. He said these firms directly employ about 18,000 Minnesotans.

Janet Moore • 612-673-7752