Table 3 Study definitions of a migraine day (N = 10)

Alpuente 2021 [39]

“A migraine day was defined as any day with moderate–severe headache or/and headache with migraine features such as photophobia, phonophobia, nausea, and vomiting.”

Barbanti 2022 [44]

“A migraine day was defined as a calendar day characterized by > 4 consecutive hours of a migraine with or without aura or a headache of any duration successfully treated with migraine-specific acute medications (triptans).”

Becker 2022 [45]

“A migraine day was defined as any calendar day in which the participant experienced a qualified migraine headache (onset, continuation, or recurrence of the migraine headache). A qualified migraine headache was defined as:

1. A migraine headache, lasting for at least four continuous hours, and meeting criteria a and/or b:

a) At least two of the following pain features: Unilateral, Throbbing, Moderate to severe, Exacerbated with exercise/physical activity

b) At least one of the associated symptoms:

• Nausea and/or vomiting

• Photophobia and phonophobia

OR

2. If the participant took a triptan or ergot-derivative on a calendar day, then it was considered as a migraine day regardless of the duration and pain features/associated symptoms.”

De Matteis 2021 [54]

“A ‘migraine day’ was defined accordingly to the ICHD-3 criteria.”

De Vriesch Lentsch 2021 [55]

“An automated and validated algorithm, based on the ICHD- 3 criteria, or intake of a triptan was used to determine whether headache days fulfilled migraine criteria.”

Iannone 2022 [58]

“A migraine day was defined as a calendar day with a headache meeting criteria for migraine (with or without aura) or a day when an acute migraine-specific medication (triptan or ergot) was used.”

Lambru 2020 [62]

“A ‘migraine day’ was defined according to the IHS classification criteria.”

Raffaelli 2022 [69]

“A migraine day was defined as any calendar day fulfilling the ICHD-3 criteria of a definite or probable migraine.”

Raffaelli 2022 [70]

“A migraine day was defined as any calendar day with a headache fulfilling the criteria of a definite or probable migraine according to the ICHD-3 classification.”

Torres-Ferrus 2021 [76]

“A migraine day was defined as any day with moderate–severe headache lasting at least 4 h or treated with analgesic. A headache day was defined as any headache lasting at least 30 min.”