Evaluation of Intra- and Interobserver Reproducibility of the New AO/OTA Classification for Distal Radius Fractures Compared with the Fernandez Classification.

 To evaluate the inter- and intraobserver reliability and reproducibility of the new AO/OTA 2018 classification for distal radius fractures and to compare it with the Fernandez classification system.  A questionnaire was applied in the Qualtrics software on 10 specialists in hand surgery who classified 50 radiographs of distal radius fractures according to the Fernandez and AO/OTA 2018 classifications and, subsequently, indicated their treatment. The questionnaire was applied in time and repeated after 4 weeks . The mean agreement between the answers, and the reliability and inter- and intraobserver reproducibility were analyzed using kappa indexes.  The mean interobserver agreement in the Fernandez classification was 76.4, and it was 59.2% in the AO/OTA 2018 classification. The intraobserver agreements were 77.3 and 56.6%, respectively. The inter- and intraobserver kappa indexes for the Fernandez classification were 0.57 and 0.55, respectively, and, in the AO/OTA 2018 classification, they were 0.34 and 0.31, respectively.  The AO/OTA 2018 classification showed a low intra- and interobserver reproducibility when compared with the Fernandez classification. However, both classifications have low intra- and interobserver indexes. Although the Fernandez classification did not obtain excellent results, it remains with better agreement for routine use.