A multi-center comparison of diagnostic methods for the biochemical evaluation of suspected mitochondrial disorders

► Diagnostic procedures for respiratory chain measurements of 5 labs were compared. ► Mouse SURF1 and control muscle, human control muscle and fibroblasts were examined. ► In almost all cases, a correct diagnosis was made. ► Sample preparation methods affect the results of the enzyme activity measurements. ► Although raw data shows inter-lab variation, normalized data give similar results.