Cr. Lines et al., A comparison of visual analog scale and categorical ratings of headache pain in a randomized controlled clinical trial with migraine patients, PAIN, 93(2), 2001, pp. 185-190
A visual analog scale (VAS) method of assessing headache pain was compared
with a standard categorical four-grade scale (4GS) in a randomized, placebo
-controlled, double-blind, clinical trial involving 792 treated migraine ou
tpatients who received oral rizatriptan 5 mg, sumatriptan 50 mg, or placebo
for a moderate or severe headache. The VAS and 4GS were equally useful in
demonstrating that the active drugs were superior to placebo at reducing he
adache pain, and in showing that the active drugs were similarly effective.
For both rizatriptan and sumatriptan, slightly larger effect sizes were ob
served with the 4GS compared with the VAS. In analyses using data combined
across all treatment groups, VAS and 4GS scores were highly correlated. Use
of the VAS imposed additional administrative burdens. These: findings sugg
est that the 4GS may be the preferred scale for assessing headache pain in
clinical trials involving adult migraineurs. (C) 2001 International Associa
tion for the Study of Pain. Published by Elsevier Science B.V. All rights r
eserved.