Table 3. Descriptive statistics and correlation of the outcomes (total and individual samples).

	All	FR	GE	PL	RU	ES	SV	UK	US
Perceived usefulness
M (SD)	2.31(1.16)	2.08(1.08)	2.60(1.16)	2.09(1.13)	2.16(1.21)	2.48(1.14)	2.16(1.20)	2.51(1.00)	2.36(1.24)
Frequency of ratings (%)
“0” = Not at all	8.8	10.9	7.6	9.6	11.8	5.6	12.4	3.7	9.5
“1” = Little	13.8	14.4	8.1	18.5	15.1	14.8	15.2	10	14.9
“2” = Moderate	31.8	38	25.5	36.6	34.8	26.6	30.3	33.9	27.8
“3” = Strong	29.2	29.1	34.2	23.6	22.2	32.3	28.9	36.3	26
“4” = Very strong	16.5	7.7	24.5	11.7	16.1	20.7	13.3	16	21.8
Adherence to measures
M (SD)	2.97 (1.00)	3.07(.94)	3.02(.92)	2.79(1.07)	2.48(1.03)	3.29(.83)	2.85(.94)	3.35(.80)	2.88(1.14)
Frequency of ratings (%)
“0” = Not at all	2.8	2.7	2.4	4.4	4	1	2	0.9	5.1
“1” = Little	5.5	3.7	3.8	8.1	10.8	2.5	5.6	2.2	7.7
“2” = Moderate	18.2	13.4	15.6	19.4	36.6	10.7	23.9	9	18
“3” = Strong	39.1	44.5	46.2	40.4	31.1	38.3	42.5	37.4	32.9
“4” = Very strong	34.5	35.7	32	27.7	17.5	47.4	26	50.6	36.3
Correlation (r)
Measures usefulness x Adherence to rules	.490**	.392**	.630**	.516**	.623**	.425**	.235**	.366**	.636**

All: N = 7,658; France (FR): N = 940, Germany (GE): N = 917, Poland (PL): N = 924, Russia (RU): N = 986, Spain (ES): N = 960, Sweden (SV): N = 922, the U.K. (UK): N = 1,105, the U.S. (US): N = 904; M = Mean; SD = Standard Deviation; due to rounding, the sum of the frequencies is not always 100%;

**p < .001.