Table 2 Results of the principal component factor analysis of the CHQ scale

Avoided leaving the house

Avoided making plans due to unpredictability of CH e.g., holidays

Felt unable to complete duties at work

Had difficulty in getting involved in leisure activities e.g., cinema, theatre, etc.?

Avoided crowded and noisy places e.g., public transport, pubs, etc.

Felt that the severity of cluster headache affected your daily activities

Been less involved in family affairs e.g., interaction with children, planning holidays

Been unable to socialise/spend time with friends and family

Been unable to achieve your daily goals and carry out routines and chores

Felt less respected by others

Had problems with close personal relationship

Felt you were a burden on family and friends

Felt self-conscious and uncomfortable about your appearance after a cluster headache attack (e.g., swelling/redness of eyes and facial sweating, etc.)

Felt that others are dismissive of your cluster headaches

Felt aggressive

Felt bad about yourself, lost self-confidence or felt worthless

Felt like harming yourself or suicidal

Been irritable, impatient or less tolerant

Been forgetful e.g., missed appointments

Been unable to take care of your appearance (e.g., take a bath, put make-up on, change clothes etc.)

Felt isolated, lonely or vulnerable

Found your pain is unbearable if untreated

Dreaded that the headache would not go away

Felt lacking in energy and constantly tired

Felt sleepy, worn out or less able to concentrate due to nocturnal attacks of CH

Had problems concentrating e.g., reading paper, watching TV, etc.

Been unable to think clearly

Felt tense or anxious

% of variance explained