Table 3.

The contribution of expected pain levels to pain in active and placebo acupuncture conditions

	Overall			Early			Late
	B	R2	P	B	R2	P	B	R2	P
Actual group allocation
Active acupuncture
Expected pain intensity	0.569	0.257	0.003	0.525	0.162	0.022	0.999	0.698	<0.001
Expected pain unpleasantness	0.515	0.231	0.005	0.509	0.193	0.012	0.993	0.654	<0.001
Placebo acupuncture
Expected pain intensity	0.602	0.277	0.001	0.633	0.212	0.005	0.719	0.493	<0.001
Expected pain unpleasantness	0.744	0.384	<0.001	0.802	0.342	<0.001	0.893	0.690	<0.001
Perceived group allocation
Active acupuncture
Expected pain intensity	0.547	0.238	0.003	0.448	0.116	0.042	0.824	0.593	<0.001
Expected pain unpleasantness	0.456	0.167	0.013	0.402	0.111	0.047	0.963	0.571	<0.001
Placebo acupuncture
Expected pain intensity	0.578	0.311	0.001	0.664	0.276	0.003	0.731	0.488	<0.001
Expected pain unpleasantness	0.675	0.392	<0.001	0.762	0.371	<0.001	0.848	0.671	<0.001

B= unstandardized beta coefficient

R2= regression coefficient

P <0.05

Regression analyses showing the contribution of expected pain intensity and expected pain unpleasantness levels at a given time point to experienced pain intensity and unpleasantness levels at a subsequent time point. Overall: expected pain levels at −2 min seen in relation to the average pain ratings during the 30-min test period. Early: expected pain levels at −2 min in relation to pain levels at 13 min. Late: expected pain levels at 13 min in relation to pain levels at 28 min.