Interferons in relapsing remitting multiple sclerosis

[...]sustained change in the EDSS score at 2 years was analysed on less than 40% of randomised patients, putting into doubt the MSCRG claim that the probabilities of sustained progression were 34.9% for placebo and 21.9% for interferon. [...]as we noted in our original paper, 50% of Avonex-treated patients, who had met the definition of treatment failure in the first year, were indeed better in the second year. [...]the deterioration in EDSS score (1 point) needed to satisfy the study's definition of progression corresponds to the inter-rater variability around 40% of the time for the low disability patients recruited. 5 There was no stated attempt to correct observer-dependent upward movement on this scale.