Headache Disorders, Primary

• San Francisco Clinical Research Center — San Francisco, California, United States
• New England Center for Headache — Stamford, Connecticut, United States
• Diamond Head Clinic — Chicago, Illinois, United States
• Michigan Head Pain & Neurological Institute — Ann Arbor, Michigan, United States

• GSK Investigational Site — Adelaide, South Australia, Australia
• GSK Investigational Site — Auckland, New Zealand
• GSK Investigational Site — Christchurch, New Zealand
• GSK Investigational Site — Hamilton, New Zealand

• Gemma V Espí López — Valencia, Spain

Not specified

Not specified

• Diamond Headache Clinic — Chicago, Illinois, United States

• Gemma V Espí López — Valencia, Spain

• Celerion — Neptune City, New Jersey, United States

• Cleveland Clinic NI, Center for Headache and Pain, Desk T-33, 9500 Euclid Avenue — Cleveland, Ohio, United States

• Physician Associates LLC — Oviedo, Florida, United States
• Clinvest — Springfield, Missouri, United States