Psychological and behavioral differences between low back pain populations: a comparative analysis of chiropractic, primary and secondary care patients

Table 4 Descriptive data of the four study samples

Variable		Sample A	Sample B	Sample C	Sample D
n		480	128	273	235
Women	%	53	10	48	55
Age	Mean	45^a	42	42	43
	S.D.	12.5	9.4	9.5	10.4
Pain duration, months	Mean	N.A.	N.A.	37	32
	S.D.	N.A.	N.A.	60	59
Neck/thoracic pain	%	N.A.	72^b	32^e	41^e
LBP	%	96	94^b	66^e	46^e
Mixed pain sites	%	57	66	2^f	13^f
Pain radiating into leg	%	21	N.A.	N.A.	N.A.
Have had LBP episode before	%	75^c	N.A.	N.A.	N.A.
Have had LBP >30 days previous year	%	66^d	N.A.	N.A.	N.A.
Population		Primary care, Chiropractic	Primary care, sick listed with risk of chronicity	Secondary care, multimodal single center	Secondary care, multimodal multi center

^aN = 134, age was recorded at the second baseline in the RCT, therefore data could be recorded only in a minority of the population
^bHaving experienced once or several times during past year
^cN = 467, ^dN = 407
^eNP or LBP as primary pain sites
^fMixed as primary pain site, S.D. – Standard Deviation, N.A. – not available, LBP – Low Back Pain

ISSN: 1471-2474