Table 1.

Main characteristics of the participants and the non-participants

	Participants	Non-participants
	(n = 155)	(n = 46)
Patients recruited by (%):
- general practitioner	39	30
- physician in orthopaedic practice	18	11
- rheumatologist in secondary care rheumatology clinic	43	59
Female (%)	65	65
Mean age in years (SD)	47 (12.6)	48 (12.1)
Previous episode(s) of shoulder pain (%)	41	35
Duration of current episode (%):
- < 3 months	26	30
- 3 – 6 months	17	13
- 6 – 12 months	24	13
- > 12 months	33	44
Mean pain score* (SD):
- at night	48 (31)	63 (25)
- during the day	51 (26)	63 (26)

* Scores on a visual analogue scale ranging from 0 'no pain' to 100 'very severe pain' (in mm).