More researchers will post the results of their trials if they are sent an email reminder according to a recent study published in The BMJ. Since 2007, the FDA has required people in the US to register their trials on ClinicalTrials.gov before they begin and to post summary results within one year of completion of the trial. However, about 75% of trials on ClinicalTrials.gov haven’t reported results and no fines have ever been issued.

The authors of the study found 379 trials on ClinicalTrials.gov with missing results. They emailed the main contact person for half of those trials reminding them that they could be fined or ineligible for future grant funding by not posting results. When the researchers checked back six months later, 24% of the trial sponsors who received an email had posted results compared to only 14% of those who weren’t sent an email. The authors conclude that sending email reminders to 10 people will result in 1 additional trial being registered.

Although the intervention led to an increase in the number of trials reporting results, a large number of trials still remain unreported on ClinicalTrials.gov. The authors suggest that “a more direct email sent by health authorities and telling recipients that they were in default and risked penalties (up to $10 000 a day) or grant funds being withheld and urging them to post their results might have more impact.”