The Impact of Differential Case Ascertainment in Clinical Registry Versus Administrative Data on Assessment of Resource Utilization in Pediatric Heart Surgery

Resource utilization in congenital heart surgery is typically assessed using administrative data sets. Recent analyses have called into question the accuracy of coding of cases in administrative data; however, it is unclear whether miscoding impacts assessment of associated resource use. We merged data coded within both an administrative data set and clinical registry on children undergoing heart surgery (2004-2010) at 33 hospitals. The impact of differences in coding of operations between data sets on reporting of postoperative length of stay (PLOS) and total hospital costs associated with these operations was assessed. For each of the eight operations of varying complexity evaluated (total n = 57,797), there were differences in coding between data sets, which translated into differences in the reporting of associated resource utilization for the cases coded in either data set. There were statistically significant differences in PLOS and cost for seven of the eight operations, although most PLOS differences were relatively small with the exception of the Norwood operation and truncus repair (differences of two days, P < .001). For cost, there was a >5% difference for three of the eight operations and >10% difference for truncus repair (US$10,570; P < .01). Grouping of operations into categories of similar risk appeared to mitigate many of these differences. Differences in coding of cases in administrative versus clinical registry data can translate into differences in assessment of associated PLOS and cost for certain operations. This may be minimized through evaluating larger groups of operations when using administrative data or using clinical registry data to accurately identify operations of interest.