Table 4. The NRS results of repeated-measures analyses of variance (ANOVA) and planned comparisons.
Variable | Main effects and interactions |
F | df |
p (power) |
ƞ2 | Planned comparisons | F | df |
p (power) |
ƞ2 | |
---|---|---|---|---|---|---|---|---|---|---|---|
Pain intensity | Placebo groupa | Placebo vs control ratings | 30.18 | 1, 39 | 0.001 (0.99) |
0.44 | |||||
Rating | 0.04 | 1, 39 | 0.85 (0.08) |
0.001 | Nocebo groupa | Nocebo vs control ratings | 21.95 | 1, 39 | 0.001 (0.99) |
0.36 | |
Experimental condition | 0.18 | 2, 39 | 0.84 (0.20) |
0.009 | Control groupa | Orange-control vs blue-control ratings | 0.24 | 1, 39 | 0.63 (0.24) |
0.01 | |
Experimental condition × Rating | 26.17 | 2, 39 | 0.0001 (0.99) | 0.57 | Difference between placebo/nocebo vs control stimulib | Placebo vs control group | 17.87 | 1, 39 | 0.001 (0.99) |
0.31 | |
Nocebo vs control group | 8.82 | 1, 39 | 0.005 (0.99) | 0.18 | |||||||
Expectancy | Placebo groupa | Placebo vs control ratings | 1.67 | 1, 39 | 0.20 (0.84) |
0.04 | |||||
Rating | 0.004 | 1, 39 | 0.95 (0.05) | 0.001 | Nocebo groupa | Nocebo vs control ratings | 3.76 | 1, 39 | 0.06 (0.78) |
0.09 | |
Experimental condition | 0.02 | 2, 39 | 0.98 (0.05) | 0.001 | Control groupa | Orange-control vs blue-control ratings | 0.56 | 1, 39 | 0.46 (0.70) |
0.01 | |
Experimental condition × Rating | 3.00 | 2, 39 | 0.0615 (0.99) |
0.13 | Difference between placebo/nocebo vs control stimulib | Placebo vs control group | 0.15 | 1, 39 | 0.71 (0.23) |
0.01 | |
Nocebo vs control group | 3.62 | 1, 39 | 0.06 (0.38) |
0.09 | |||||||
Fear | Placebo groupa | Placebo vs control ratings | 0.63 | 1, 39 | 0.43 (0.47) |
0.02 | |||||
Rating | 0.11 | 1, 39 | 0.75 (0.29) |
0.003 | Nocebo groupa | Nocebo vs control ratings | 3.30 | 1, 39 | 0.08 (0.70) |
0.08 | |
Experimental condition | 2.90 | 2, 39 | 0.07 (0.99) |
0.13 | Control groupa | Orange-control vs blue-control ratings | 0.21 | 1, 39 | 0.65 (0.55) |
0.01 | |
Experimental condition × Rating | 2.02 | 2, 39 | 0.15 (0.99) |
0.09 | Difference between placebo/nocebo vs control stimulib | Placebo vs control group | 0.06 | 1, 39 | 0.81 (0.14) |
0.001 | |
Nocebo vs control group | 2.58 | 1, 39 | 0.12 (0.45) |
0.06 |
a Within-group comparisons.
b Between-group comparisons.