The authors examined the impact of formal reporting of a no driving recommendation in Ontario where patients had easy access to medical services and a data reporting system that could link to emergency room records. Ontario's reporting system began paying providers for completing a warning report in 2006, thus leading to a rise in referrals. Patients who received a warning over a 4 year interval were included in the study. The incidence of emergency room visits for motor vehicle accidents in the year before referral was compared to the incidence after referral for each individual patient in a self-matched cross-over design. The result? They found a 45% reduction in the annual rate of crashes per 1000 patients after the warning (4.76 vs. 2.73). In other words, if you told 1000 patients they were unsafe to drive, you would prevent 2 accidents.A warning to stop driving was also associated with some potential harms. Patients warned to stop driving had greater emergency room visits for depression and made fewer visits to the referring doctor than the year before. 10% of patients made no visits the following year despite having made at least 2 visits the year prior.
via geripal.org