Usefulness of administrative databases for risk adjustment of adverse events in surgical patients

The aim of this study was to assess the usefulness of clinical-administrative databases for the development of risk adjustment in the assessment of adverse events in surgical patients.

The study was conducted at the Hospital of Navarra, a tertiary teaching hospital in northern Spain. We studied 1602 hospitalizations of surgical patients from 2008 to 2010. We analysed 40 comorbidity variables included in the National Surgical Quality Improvement (NSQIP) Program of the American College of Surgeons using 2 sources of information: The clinical and administrative database (CADB) and the data extracted from the complete clinical records (CR), which was considered the gold standard. Variables were catalogued according to compliance with the established criteria: sensitivity, positive predictive value and kappa coefficient >0.6.

The average number of comorbidities per study participant was 1.6 using the CR and 0.95 based on CADB (p<.0001). Thirteen types of comorbidities (accounting for 8% of the comorbidities detected in the CR) were not identified when the CADB was the source of information. Five of the 27 remaining comorbidities complied with the 3 established criteria; 2 pathologies fulfilled 2 criteria, whereas 11 fulfilled 1, and 9 did not fulfil any criterion.

CADB detected prevalent comorbidities such as comorbid hypertension and diabetes. However, the CABD did not provide enough information to assess the variables needed to perform the risk adjustment proposed by the NSQIP for the assessment of adverse events in surgical patients.