To Örebro University

INTRODUCTION: Quality registers are used for quality assessment, cost analyses, and research regarding outcomes of surgical and non-operative treatments. As the Swedish Fracture Register (SFR) expands, and is used as a platform for randomized trials, assuring reliability and accuracy of the data is essential. AIM: This study aimed to investigate the accuracy of the radiographic classification data for proximal humerus fractures recorded in the SFR.

METHOD: All radiographic images of 171 patients with a proximal humerus fracture registered in the SFR between 2019 and 03-01 and 2019-08-31 at 3 hospitals were included. The radiographs were independently assessed at 2 occasions >3 weeks apart by 1 surgeon at each center and IRR was calculated to validate the modification of the AO/OTA classification used in the register. A "gold standard" classification for each patients' images was then established with a consensus discussion involving 4 shoulder surgeons. The gold standard classification was compared with the classification registered in the SFR.

RESULTS: Intra-rater reliability was moderate (kappa 0.549-0.596) with percent agreement (PA) 61-66 %. Inter-rater reliability was also moderate (kappa 0.508-0.557) with PA 58-62 %. Accuracy of the SFR recordings compared with gold standard was fair with kappa 0.36 (95 % CI 0.297-0.425) and PA 44 %.

CONCLUSION: For registers to be of use the accuracy of data is essential as well as coverage, completeness, validity and reliability. The modified AO/OTA classification for proximal humerus fractures used in the SFR had moderate reliability but registered data only fair accuracy compared with a gold standard. This questions its value as a base for scientific research and clinical decisions.