This study aims to evaluate the usefulness of an app-based headache diary in episodic migraine patients. For this the investigators will conduct a randomized clinical trial with a crossover design, using the app-based diary and a traditional paper-based headache diary. The patients will use each diary for 13 weeks. The investigators will evaluate diary adhesion after each 13-week period, and also evaluate headache burden and prophylactic medication compliance at the beginning, at the crossover point, and at the end of the study, and acute headache medication use through diary records. The investigators will also evaluate user preference through a questionnaire at the end of the study.

Headache is one of the main reasons for seeking primary health care and an important cause of absenteeism at work and decreased quality of life in the population, being the major neurological cause of disability in young adults and middle-aged adults. Although the subjectivity of the complaints and the great intra and inter-individual variability of clinical presentations hinder its epidemiological study, it is estimated that the overall prevalence of headache throughout life is 66% (46-78% in tension-type headache; 14-16% for migraine and 0.1-0.3% for cluster headache). Migraine, in particular, is a primary headache with an estimated prevalence of 11 to 14% in adult women and 4 to 9% in adult men. In addition, it is assumed that up to 20% of absences from work can be attributed to headaches, with the inherent socio-economic impacts.

Headache is a very frequent complaint in the primary care setting. However, the differential diagnosis can be complicated at this level. Primary headache diagnosis is made almost exclusively through clinical history taking, for this purpose clinicians use the criteria in the International Classification of Headache Disorders, currently on its 3rd version. However, its application is often challenging and time-consuming, especially in a primary care setting, where physicians are very limited on time. Nonetheless, a correct diagnosis is essential, as treatment varies among the primary headaches and also within the same headache type according to its frequency.

The episodic nature of headaches increases the risk of memory bias towards more severe or more recent crises. To avoid this, patients nowadays use a paper calendar. This calendar makes it possible to monitor, more reliably, the response to therapy and to identify the need for any adjustments.

However, the paper calendar has many limitations, such as the possibility of filling in immediately before consultations instead of non-biased daily records. In addition, the paper or card used can be lost, is more easily forgotten, and cannot be consulted remotely by the attending physician. In the current digital landscape, we have seen a transition in registration methods for semi-automated electronic platforms, considered more practical and appealing to users. However, most in-app headache diaries are not validated and are mainly written in English.

Having these ideas in mind the investigators decided to develop an app-based electronic headache diary that would not only permit a better adhesion to follow-up but also remote monitoring of headache patients. To study the applicability and the usefulness of this idea the investigators designed a randomized clinical trial with a crossover design where episodic migraine patients would be randomized to the use of the app or of a paper headache diary. Each patient would use the app and the paper diary for a period of 13 weeks.

In the paper and electronic diary patients will record headache days, headache type (migraine or tension-type headache), headache intensity with a scale from 0 to 10, intake of acute headache medication, missing work days due to headache, and recurrence to the emergency department due to headache.

The investigators will also measure headache burden with the portuguese versions of HIT-6, MSQ v2.1 and MiDAS scales and quality of life with the WHOQOL-BREF at the beginning, at the crossover point, and at the end of the study. Also, the study will evaluate prophylactic medication compliance at the beginning, at the crossover point, and at the end of the study through a questionnaire. User preference will be measured through a questionnaire, using a Likert type scale, at the end of the study.

Inclusion Criteria:

• Patients with episodic migraine, diagnosed for more than 6 months.
• Patients with at least 4 headache days per month and a maximum of 15 headache days per month.

Exclusion Criteria:

• Patients with major psychiatric illness.
• Patients participating in another clinical trial.
• Patients who do not meet diagnostic criteria for episodic migraine according to ICHD-3.
• Illiterate patients or those who are unable to fill the records independently.
• Patients with a previous history of filling in a headache calendar, in the 3 months prior to randomization.
• Patients who do not use a cell phone with Android OS.
• Patients who cannot read or write in Portuguese.