Observer variation in the Lauge-Hansen classification of ankle fractures. Precision improved by instruction.

We investigated whether instruction can decrease the variation in the classification of ankle fractures. The radiographs of 100 consecutive ankle fractures were twice assessed by 8 observers, using the Lauge-Hansen classification system. 1 group of 4 observers was given special instruction between 2 assessments. Without instruction the interobserver variation was identical at the first and second assessments. After instruction, the agreement increased from 0.66 to 0.75. These results show that the variation in the Lauge-Hansen classification system can be reduced by instruction.