Analysis of the International Classification of Headache Disorders for diagnosis of migraine and tension-type headache in children.

In 2004, the revised International Classification of Headache Disorders (ICHD-II) was published. This study evaluates: (1) the results obtained from applying ICHD-II to children with primary headaches to distinguish between migraine without aura (MO) and tension-type headache (TTH); and (2) the results obtained from introducing modifications of the classification criteria for MO as suggested by various authors. There were 200 participants (93 males, 107 females; age range 3-17 y, mean 9 y 8 mo [SD 2 y 7 mo]). According to the ICHD-II, MO compared with TTH was characterized by: higher intensity of pain; higher frequency of associated symptoms; and higher number of precipitating factors. The significant difference found between patients with MO/probable MO and those with TTH/probable TTH for the variables used in the ICHD-II shows that these variables describe the two forms well. However, 15.5% of children proved to be unclassifiable, mainly because they could not give information for some criteria; other reasons for this were too short a duration of episodes and the possible overlap of criteria describing probable MO and probable TTH. The frequency of one variable, pulsating pain, significantly increased with age. Reduction of duration to 1 hour for MO produced a statistically non-significant increase in the number of children with MO. Behaviour during attacks was found to be simple to apply in evaluating intensity and therefore was introduced as a new criterion. Severe intensity was related to MO, whereas moderate or low-intensity was related to TTH.