Abstract
Background Previous headache trigger studies have primarily utilized checklists to measure beliefs about triggers. While this work has defined the diversity of beliefs across headache sufferers, the strength of association and the frequency at which these triggers are encountered remain unexplored. Objective To measure the strength of association, frequency of encounter, and influences on trigger beliefs and perceptions using a laboratory assessment task. Methods This cross-sectional observational study, part of the HACOGS project, included adult current migraine, tension-type, or cluster headache sufferers. Participants rated the chances they would experience a headache if they were to encounter a specific trigger and the number of days per month they experience that trigger for 33 common triggers. Results All 300 participants contributed data on all triggers, with little missing data (1.2%). All triggers exhibited a high degree of inter-individual variability on the strength of association and encounter perceptions. Many triggers were perceived to be encountered daily (e.g., caffeine, air conditioning), and a full range of perceptions were observed for each trigger. Stress (75% chance of headache), missing a meal (60%), and dehydration (60%) were the triggers with the greatest potency beliefs. Only 8-15% of these beliefs were related to individual differences and 26-27% to the triggers themselves. Conclusions Participants expressed diverse beliefs and perceptions about the strength of many common headache triggers. Variation in these beliefs was not associated with individual differences or the triggers themselves. This finding supports the importance of measuring more than just the presence-absence of trigger beliefs.