Table 8

Sequential multiple regression analysis of BIPQ items predicting BPS

Variable, n=200	B=unstandardised		β=standardised		Adjusted R²
Variable, n=200	B (95% CI)	SEB	β (p value)	R²	Adjusted R²
BIPQ total score	0.154 (0.110 to 0.200)	0.024	0.366 (<0.0001)	0.516	0.491
Consequences	0.314 (0.125 to 0.502)	0.095	0.223 (0.001)	0.444	0.414
Timeline	0.410 (0.221 to 0.600)	0.096	0.255 (<0.0001)	0.464	0.435
Personal control	−0.322 (-0.500 to 0.143)	0.09	−0.205 (<0.0001)	0.449	0.420
Treatment control	−0.173 (-0.376 to 0.030)	0.103	−0.106 (0.095)	0.420	0.390
Identity	0.222 (0.020 to 0.424)	0.103	0.150 (0.032)	0.426	0.396
Illness concern	0.437 (0.250 to 0.623)	0.095	0.294 (<0.0001)	0.471	0.443
Coherence	0.024 (-0.165 to 0.214)	0.096	0.016 (0.803)	0.412	0.381
Emotional representation	0.220 (0.055 to 0.385)	0.084	0.183 (0.009)	0.433	0.402

Significant at Bonferroni 0.0063 level (two-tailed).
BPS, Back Performance Scale; BIPQ, Brief Illness Perception Questionnaire; BIPQ1, consequences; BIPQ2, timeline; BIPQ3, personal control; BIPQ4, treatment control; BIPQ5, identity; BIPQ6, illness concern; BIPQ7, coherence; BIPQ8, emotional representation.