Data quality and auditing within the Netherlands Heart Registration: using the PCI registry as an example

AIM: The aim of this article is to present the method and results of the data quality control system and audit within the Netherlands Heart Registration (NHR) using data of patients treated with percutaneous coronary intervention (PCI) in the Netherlands as an example. METHODS: The NHR is a Dutch nationwide registry of all cardiac interventions, comprising data from all 71 hospitals, of which 30 are cardiac intervention or heart centres. Each year, within the NHR, data validation and verification is performed by standard quality controls and monitoring visits (audits). For the audit in 2019, a sample of 50-100 medical records of patients treated with PCI in 2016 and 2017 were reviewed in each hospital by an independent auditor. The data received by the NHR were compared with the information in the hospitals' medical records. In total 12 patient characteristics, 5 intervention variables and 3 outcome variables were screened. The value of a variable was considered discrepant if more than 10% of the medical records reviewed regarding this variable were not consistent with the reported data received by the NHR. RESULTS: For all variables together, the consistency was high, 97.6%. All variables, except multivessel disease (9.3% discrepancy in the 2622 medical records reviewed), had an accuracy above 95%. CONCLUSION: The results of the audit of the PCI medical records show that the overall quality of the data is high. For variables such as multivessel disease it is important to improve knowledge of the definitions and to train all those involved in the registration process.