Headache

Abstract

Migraine is a common primary headache disorder with effective evidence-based preventive medications that reduce the frequency and severity of attacks. Cluster headaches and other trigeminal autonomic cephalalgias are uncommon with evidence-based acute treatment options available for cluster headache and preventive medications for cluster headache, paroxysmal hemicrania, and SUNCT.

Appendix: Definition of Class I and Class II Studies

Class I: A randomized, controlled clinical trial of the intervention of interest with masked or objective outcome assessment, in a representative population. Relevant baseline characteristics are presented and substantially equivalent among treatment groups or there is appropriate statistical adjustment for differences.

The following are also required:

• a. Concealed allocation

• b. Primary outcome(s) clearly defined

• c. Exclusion/inclusion criteria clearly defined

• d. Adequate accounting for drop outs (with at least 80% of enrolled subjects completing the study) and crossovers with numbers sufficiently low to have minimal potential for bias.

• e. For noninferiority or equivalence trials claiming to prove efficacy for one or both drugs, the following are also required:

  • 1. The authors explicitly state the clinically meaningful difference to be excluded by defining the threshold for equivalence or noninferiority.

  • 2. The standard treatment used in the study is substantially similar to that used in previous studies establishing efficacy of the standard treatment. (e.g., for a drug, the mode of administration, dose, and dosage adjustments are similar to those previously shown to be effective).

  • 3. The inclusion and exclusion criteria for patient selection and the outcomes of patients on the standard treatment are comparable to those of previous studies establishing efficacy of the standard treatment.

  • 4. The interpretation of the results of the study is based upon a per protocol analysis that takes into account dropouts or crossovers.

Class II: A randomized controlled clinical trial of the intervention of interest in a representative population with masked or objective outcome assessment that lacks one criteria a–e above or a prospective matched cohort study with masked or objective outcome assessment in a representative population that meets b–e above. Relevant baseline characteristics are presented and substantially equivalent among treatment groups or there is appropriate statistical adjustment for differences.