Imputation rules and key sensitivity analyses
death
REGRESSION
In the primary analysis, for each patient, all available ALSFRS-R scores will be included in the linear regression model to estimate the monthly decline. The following rules for handling missing data will be applied: (i) for deceased patients, as death is clearly a poor outcome and there is no consensus on an alternative score, the lowest score (zero) will be assigned at the time of death, and (ii) for withdrawals or LTF patients without a post-randomization assessment of the ALSFRS-R score, the monthly decline of ALSFRS-R will be imputed using the “nearest neighbor” procedure [