BioTenCer: Biofeedback as Preventive Treatment in Tension Type Headache

Inclusion Criteria: * 18 years of age inclusive or older, at the time of signing the informed consent. * A diagnosis of TTH according to the criteria of the International Classification of Headache Disorders 3rd edition (ICHD-3) * History of at least 6 days or more with TTH per 28-day period in the 3 months prior to screening (as recalled by the subject). * Frequency of at least 6 days or more with TTH per 28-day period, confirmed by daily diary entries in the baseline period. * At least three months of experience with smartphone and access to an iOS or Android phone at home. * Capability of giving signed informed consent which includes compliance with the requirements and restrictions listed in the informed consent form (ICF) and in this protocol. * Onset of TTH (and migraine, if present) before the age of 50 years. * The onset of TTH should be present for at least 1 year prior to inclusion. Exclusion Criteria: * Subject does not master a Scandinavian language at a level sufficient to fully understand the written and verbal study information. * Subject is unable to differentiate TTH from other concomitant headaches. * A history of more than 1 migraine attack per month on average in the last year, as recalled by the patient. * Frequency of more than 1 migraine attack per month during the baseline period, as confirmed by daily diary entries. * Subjects diagnosed with trigeminal autonomic cephalalgias and cranial neuralgias. * Subjects with secondary headache conditions with…