You’ve heard it time and time again: studies need you! You with Parkinson’s disease. You without Parkinson’s disease (PD)!

A recent paper in The Journal of the American Medical Association backs us up. A long list of investigators looked at more than 1,000 clinical trials (not just PD ones) approved by six ethics committees spread across France, Switzerland and Canada. Of 1,017 studies, 253 were discontinued. That means almost a quarter of clinical trials from those sites never made it to analysis. Did the intervention work? Who knows.

The most cited reason for discontinuation was, unsurprisingly, poor participant recruitment. Practically 10 percent (9.9) of all the studies in this analysis (101/1,017) were stopped because they didn’t have enough volunteers. Trials need a certain number of patients — and oftentimes control volunteers — to have enough “power.” That is, the findings need to be significant enough to be generalized to the greater patient population.

What can you do? Register for Fox Trial Finder, which matches users to Parkinson’s studies they may be eligible for based on factors like location, age and medical history.

Want to know more? Read the article in JAMA.