A prospective baseline versus on-treatment study assessing patient perceptions of using a smaller needle when injecting intramuscular interferon beta-1 a (Avonex).

This study assessed patient perceptions of using a smaller needle (1-inch, 25-gauge) to administer weekly intramuscular (IM) interferon beta-1 a (IFNbeta-1 a [Avonex]) injections. Patients received 1 IM IFNbeta-1 a injection at baseline using the standard needle (1.25-inch, 23-gauge), followed by 4 weekly injections using the smaller needle.