Study subject characteristics.

Characteristics of the study population (upper part), clinical and subclinical response of patients with MS to IFNβ-therpay (middle part) and tolerability of influenza vaccination and incidence of influenza-like illnesses (lower part). Abbreviations: interferon-beta (IFNβ), IFNβv-treated patients with multiple sclerosis (MS IFNβ), not applicable (N.A.), Expanded Disability Status Scale (EDSS), intramuscular (im), subcutaneous (sc), once weekly (OW), three times per week (THW), every other day (EOD).*indicates p