Question

AVONEX and MS. An issue of Inside MS contained an article describing AVONEX (interferon beta-la), a drug used in the treatment of relapsing forms of multiple sclerosis (MS). Included in the article was a report on "... adverse events and selected laboratory abnormalities that occurred at an incidence of 2% or more among the 158 multiple sclerosis patients treated with 30 mcg of AVONEX once weekly by IM injection." In the study, 158 patients took AVONEX and 143 patients were given placebo.

(a) Is this study observational or is it a designed experiment?

(b) Identify the treatment group, control group, and treatments.

Short answer

Part (a) Designed experiment.

Part (b) Treatment group: 158 patients.

control group: 143 patients.

treatments: AVONEX and placebo.

Step-by-step solution

Part (a) Step 1. Given information.

The given statement says that 2% or more among the 158 patients with multiple sclerosis were given 30 mcg of AVONEX once weekly by IM injection.

In the research, 158 patients received AVONEX and 143 received a placebo.

Part (a) Step 2. Classify the given study as either observational or a designed experiment.

The given study is a case of a designed experiment.

Part (b) Step 1. Identify the treatment group, control group, and treatments.

Treatment group:

The treatment group includes the 158 patients that were given 30 mcg of AVONEX once weekly.

Control group:

The control group includes 143 patients.

These are patients that were given the placebo.

Treatments:

AVONEX and placebo are the treatments given to the patients.