In our September 2012 What’s New in the Patient Safety World column “Canadian Paediatric Adverse Events Study” we discussed a study using a trigger tool to assess rates of adverse events in hospitalized pediatric patients in Canada (Matlow 2012). The overall rate of adverse events was 9.2%. The overall rate of adverse events was almost 3 times higher in the academic centers but this was largely driven by a higher rate of non-preventable adverse events.
A new study (Ahuja 2012) shows that the medical error rate in pediatric inpatients in the US is proportionate to the number of chronic conditions that the child has. Those researchers used the large KID (2006 Kids’ Inpatient Database) database and ICD-9-CM codes for iatrogenic medical errors. While the overall rate of medical errors was 3.0 per 100 discharges, there was a big disparity between rates for children with and without chronic conditions. For those without chronic conditions the rate was 1.3 per 100 discharges whereas for those with one or more chronic conditions it was 5.3 per 100 discharges. Moreover, the rates increased in proportion to the number of chronic conditions, though in the adjusted models this tended to level off somewhat once 3 chronic conditions were reached.
They also noted that the error rates were higher in urban hospitals, teaching hospitals, children’s hospitals, and general hospitals with children’s units. These hospitals also had higher numbers of patients with chronic conditions.
So how does this study mesh with the Canadian Paediatric Adverse Events Study? The adverse event rates were higher in the Canadian study. However, that largely reflects different methodologies and not measuring exactly the same things. The Canadian study utilized a trigger tool methodology, which has been shown to uncover many more events than seen in studies using administrative databases only. The use of ICD-9_CM coding for errors in the Ahuja study would be expected to pick up considerably fewer adverse events. So that latter study certainly does not imply that medical error rates are any lower in the US than in Canada.
But both studies add considerably to our knowledge base. The Canadian study also showed higher overall adverse event rates in teaching hospitals (though the higher rates were primarily in the nonpreventable category) and this may well be due to the higher percentage of patients with chronic illnesses at those hospitals as well. It certainly makes sense that patients who are sicker and on more complex medication regimens and interact with the healthcare system more often are probably going to be the most vulnerable to medical errors. We certainly see that in the adult population as well.
Matlow AG, Baker GR, Flintoft V, et al. Adverse events among children in Canadian hospitals: the Canadian Paediatric Adverse Events Study. CMAJ 2012; July 30, 2012 First published July 30, 2012, doi: 10.1503/cmaj.112153
July 30, 2012
Ahuja N, Zhao W, Xiang H. Medical Errors in US Pediatric Inpatients With Chronic Conditions. Pediatrics 2012; 130: e786-e793 Published online September 10, 2012