Despite our frequent comment that double checks are a relatively “weak” safety intervention, we have noted that the literature supports a medication error reduction of about 30% when using a double check system (see our July 15, 2008 Patient Safety Tip of the Week “Heparin Flushes.....Again!”).
The most recent edition of the ISMP Medication Safety Alert includes an article “Santa checks his list twice. Shouldn’t we?” that puts the independent double check process in perspective. They cite some studies done in community pharmacies that show double checks found errors in 2.6% to 4.2% of cases, about half of which were potentially significant. And the “average’ error checking rate is about 5%. But they also discuss how difficult it is for someone to pick up their own errors (because of phenomena such as confirmation bias) and point out that double checks work best when they are performed truly independently.
They recommend that double checks be limited to hi-alert medications (like insulin, heparin, chemotherapy, TPN, etc.) and to very complex processes or hi-risk patient populations. Don’t use double checks when some more fundamental re-engineering of the system is needed. And learn from errors uncovered during the double check process. They do suggest continuation of “natural” double checks you are already doing, such as when a nurse checks the accuracy after a pharmacist has dispensed a drug. We’ll second that one - particularly since over-reliance on computers often discourages those double checks (see our November 3, 2009 Patient Safety Tip of the Week “Medication Safety: Frontline to the Rescue Again!”). We love the concept in John Nance’s book where everyone always asks themselves “Could what I’m about to do cause harm to this patient?” (see our June 2, 2009 Patient Safety Tip of the Week “Why Hospitals Should Fly…John Nance Nails It!”).
ISMP. Santa checks his list twice. Shouldn’t we? Medication Safety Alert. Acute Care Edition. December 17, 2009