TABLE 2.

Means ± standard deviations for the study outcomes per group

	Positive suggestions group (n = 52)	Negative suggestions group (n = 46)	Control group (n = 42)
Process measure a
Postsuggestions expected itch	3.47 ± 2.12	4.05 ± 2.33	4.43 ± 2.42
Itch scores for scratching sounds b
Averaged across HF amplitude	2.35 ± 2.05	2.16 ± 1.84	2.52 ± 2.41
Averaged across HF amplitude (sqrt)	1.76 ± 0.53	1.71 ± 0.49	1.78 ± 0.62
Separate for HF amplitude
… −10 dB	2.35 ± 2.00	2.08 ± 1.68	2.35 ± 2.34
… Original	2.33 ± 2.17	2.17 ± 1.82	2.50 ± 2.47
… +10 dB	2.38 ± 2.12	2.22 ± 2.09	2.73 ± 2.56
… −10 dB (sqrt)	1.39 ± 0.66	1.30 ± 0.63	1.31 ± 0.81
… Original (sqrt)	1.37 ± 0.69	1.33 ± 0.64	1.37 ± 0.79
… +10 dB (sqrt)	1.38 ± 0.70	1.31 ± 0.71	1.43 ± 0.83
Itch scores for rubbing sounds b
Averaged across HF amplitude	2.22 ± 1.91	2.06 ± 1.76	2.00 ± 2.10
Averaged across HF amplitude (sqrt)	1.72 ± 0.50	1.68 ± 0.48	1.64 ± 0.56
Separate for HF amplitude
… −10 dB	2.03 ± 1.78	1.95 ± 1.64	1.73 ± 2.01
… Original	2.24 ± 2.03	2.02 ± 1.72	1.97 ± 2.08
… +10 dB	2.37 ± 2.06	2.17 ± 1.98	2.29 ± 2.30
… −10 dB (sqrt)	1.28 ± 0.63	1.24 ± 0.64	1.08 ± 0.77
… Original (sqrt)	1.34 ± 0.68	1.27 ± 0.65	1.18 ± 0.77
… +10 dB (sqrt)	1.40 ± 0.65	1.29 ± 0.72	1.30 ± 0.78

Abbreviations: dB, decibel; HF, high frequency; sqrt, square root transformed.

^a n = 4 missing.

^b n = 6 missing.