Figure 2.

Schematic of minimal clinically important difference analyses. ALSFRS-R speech question subscore: “How is your speech?” Possible responses: (4) normal speech process, (3) detectable speech disturbance, (2) intelligible with repeating, (1) speech combined with nonvocal communication, (0) loss of useful speech. In each analysis, the participants who reached the threshold of change on the ALSFRS-R subscore were compared with the participants who did not reach the threshold of change on the ALSFRS-R subscore (i.e., “no change” or “stayed at score of __”). MCID = minimal clinically important difference; ALSFRS-R = ALS Functional Rating Scale–Revised; ROC = receiver operating characteristics.