Objective: The multi-national and multi-institutional collection of data on outcomes in Congenital Heart Surgery (CHS) provides the possibility of analysis of results of treatment and may result in further improvement of the quality of care. The verification of data as far as the completeness and accuracy is necessary to give confidence to all sides--the patients, centers and regulatory authorities. The source data verification (SDV), although difficult, appears possible even in such a large-scale database.
Methods: Out of 5.274 patients and 5.612 procedures data of 2003, collected in the database, 1.703 (32.3%) and 1.895 (33.8%), respectively, have been verified at five sites on following fields: IPPV time, date of birth, date of admission, date of surgery, date of discharge/mortality, body weight, case category, CPB time, AoX time, Circulatory arrest time. SDV was performed at five sites by two database officers using the sources of information different to the local copy of the database (patients' files, operation notes, perfusion charts, OR Books). Verification was performed between June 1st and July 31st 2004. Statistical analysis was performed using R-project software, ver. 2.0.0. and Welch's t-test for comparison of continuous variables. P-value >0.05 was used as statistically significant difference between groups.
Results: Pre- and post-verification mortalities in all groups showed no significant differences although seven deaths out of 68 (10.27%) were missed. None of the other verified fields showed significant differences after verification.
Conclusions: Source Data Verification showed no statistically significant differences between verified and non-verified data on 30 days mortality, LOS, age, body weight, CPB time, AoX and Circulatory arrest time. IPPV time was not available in 58.6% procedures.