Appendix 1

Factor analysis:
S10	I am worried that my asthma may interfere with the lives of the people closest to me	0.73
S8	Being asthmatic often makes me feel depressed	0.71
S15	Being asthmatic often makes me feel angry	0.69
S11	My asthma is severe	0.66
S16	I can’t enjoy a full life because of my asthma	0.65
S14	I worry that I might die from asthma	0.64
S5	I feel different from other people because I am an asthmatic	0.63
S1	I worry about the long term effects of asthma on my health	0.62
S3	Even when I feel well, I worry about getting an attack of asthma	0.56
S13	Asthma makes me physically less attractive	0.51
(S17	The people who are closest to me seem overly protective of me because of my asthma	0.48)
Factor 2. Doctor-patient relationship
S30	My doctor tells me everything I want to know about my asthma	0.82
S22	I feel understood by my doctor	0.77
S7	I have confidence in my doctor’s management of my asthma	0.75
S28	My doctor has helped to make my asthma better	0.71
S18	My doctor told me what the medicines he/she prescribed would do for me	0.63
S4	I wish that my doctor talked more to me about my asthma	0.61
Factor 3. Stigma/pessimism
S27	I avoid other people who know I am an asthmatic	0.66
S12	It embarrasses me to use asthma inhalers or other asthma medicines in public	0.61
S29	Looking towards the future, I feel certain that my asthma will get better	0.50
(S25	I feel somehow to blame for being an asthmatic	0.49)
Factor 4. Self-efficacy
S21	I know when an asthma attack is beginning	0.65
S20	I have confidence in my ability to cope with an asthma attack	0.59
S19	I don’t do anything about my asthma until it gets bad	0.50
(S6	I know what things start my asthma attacks	0.48)
Each question was scored using a 5 point Leikert scale