Reliability Of A Surgeon-Reported Morbidity And Mortality Database: A Comparison Of Short-Term Morbidity Between The Scoliosis Research Society And National Surgical Quality Improvement Program Databases

BACKGROUND: There exists a lack of comparison between large national healthcare databases reporting surgical morbidity and mortality. Prior authors have expressed concern that the Scoliosis Research Society (SRS) membership may have underreported complications in spinal surgery. Thus, the purpose of the present study was to compare the incidence of morbidity between the SRS and National Surgical Quality Improvement Program (NSQIP) databases.

METHODS: We reviewed patients enrolled between 2012 and 2013, with a total of 96,875 patients identified in the SRS dataset and 15,909 in the combined adult and pediatric NSQIP dataset. Patients were matched based on diagnostic category,and a univariate analysis was used to compare reported complication rates in the categories of perioperative infection, neurologic injury, and mortality. The SRS database only requires detailed demographic data reporting on patients that have had a complication event. We compared the demographics and comorbidities of this subgroup, and used this as a surrogate to assess the potential magnitude of confounders.

RESULTS: Small differences existed between the SRS and NSQIP databases in terms of mortality (0.1% v. 0.2%), infection (1.2% v. 2%), and neurologic injury (0.8% v. 0.1%) (p<0.001 for each comparison). Infection rates were consistently lower across multiple diagnostic sub-categories in the SRS database, whereas neurologic injury rates were consistently lower in the NSQIP database. These differences reached statistical significance across several diagnostic subcategories, but the clinical magnitude of the differences was small. Amongst the patients with a complication, modest differences in comorbidities existed between the two cohorts.

CONCLUSION: Overall, the incidence of short-term morbidity and mortality was similar between the two databases. There were modest differences in comorbidities, which may explain the small differences observed in morbidity. Concerns regarding possible under-reporting of morbidity and mortality data by the SRS membership seem largely unfounded. This study may be useful for future investigators using the NSQIP and SRS datasets.