Table 4.

Changes from baseline, postintervention, and posttest in expected pain relief by amitriptyline.

	Expected pain relief by amitriptyline
	F value	Probability (P)	Effect size (d)
ANOVA	F (2,42)	P	d
Time	6.28	<0.05	1.1
ANOVA	F (2,42)	P	d
Group	1.56	0.22	0.39
ANOVA	F (2,40)	P	d
Time × group	0.99	0.38	0.26
Time	F (2,40)	P	d
Baseline vs postintervention	3.03	0.09	0.54
Time	F (2,40)	P	d
Postintervention vs posttest	6.6	<0.05	0.79
Time × group	F (2,40)	P	d
Baseline vs postintervention	0.76	0.39	0.27
Time × group	F (2,40)	P	d
Postintervention vs posttest	0.73	0.4	0.26

The results of a repeated-measures analysis of variance (ANOVA) for the main effect time and interaction of time and group (ie, difference between both groups in baseline, postintervention, and posttest changes) with F values (F), probability (P) and effect size Cohen d (d). In addition, contrasts of time (ie, both groups together) comparing expectation ratings at baseline vs postintervention as well as ratings at postintervention vs posttest. Bold indicates only the comparison between postintervention and posttest yielded a significant difference. The contrast time × group (ie, comparing the change from one data point to another between groups) did not result in significant differences.