Mechanical versus visual evaluation of urinary flow curves and patterns

Flow curves from 100 consecutive patients were obtained using the Urodyn 1000 mictiograph. Four observers evaluated the flow curves blindly, i.e. without access to the mechanically estimated values. Further, the flow curve pattern was decided upon in each case. The 4 observers agreed very meticulously in the evaluation while they disagreed with the mechanically obtained results. The visually read values were significantly lower than the mechanically determined ones. At the same time the difference in Qmax was most pronounced in abnormal curves. In conclusion the mechanical evaluation of uroflow curves may be misleading and should not replace the visual evaluation.