Current classification systems for diagnosing recurring headaches util
ize sets of specific criteria. To determine the usefulness of these cr
iteria in the practical application of diagnosing headache patients, 6
98 headache specialists were asked to review four case vignettes of he
adache patients and assign a diagnosis. They also ranked International
Headache Society (IHS) criteria along with other features commonly us
ed in the diagnosis of headaches in order of importance. There was no
difference in ranked importance for the specific criteria posed by the
IHS compared with commonly used criteria not included within the IHS
system. A large majority of the respondents combined IHS features with
other associated features not used in the IHS system as the basis of
diagnostic assignment. These results raise a question about the accept
ance and utilization of the IHS system as a basis for diagnoses. They
also suggest that there is a need to educate health care providers abo
ut the appropriate use of the current IHS criteria to increase reliabi
lity of headache diagnosis.