Table 2.

Summary of results of the subjective measures on day 1 and day 8

	Mean ± s.e.mean per treatment				Treatment effect
	CET	PLA	MEQ	DEX	F	d.f.	P	N
Day 1
Subjective driving quality
Pre-test (mm)	78.5 ± 4.6	73.7 ± 6.3	79.1 ± 6.5	68.7 ± 6.3	1.06	3,39	NS	15
Post-test (mm)	64.7 ± 6.9	67.9 ± 6.6	55.1 ± 7.5b	51.5 ± 8.0a	4.55	3,39	0.008	15
Sleep questionnaire
Time before asleep (min)	18.9 ± 4.6	12.4 ± 2.2	18.8 ± 4.5	22.6 ± 5.0	1.06	3,39	NS	15
Number of awakenings	1.1 ± 0.3	1.1 ± 0.3	1.0 ± 0.3	1.1 ± 0.4	0.00	3,39	NS	15
Sleep (h)	6.7 ± 0.3	7.6 ± 0.2	7.2 ± 0.2	7.1 ± 0.3	2.05	3,39	NS	15
Number of complaints	2.6 ± 0.9	1.0 ± 0.4	1.7 ± 0.9	2.7 ± 0.9	1.23	3,39	NS	15
Day 8
Subjective driving quality
Pre-test (mm)	86.7 ± 3.0	77.5 ± 5.8	73.0 ± 4.2	72.2 ± 6.4	2.66	3,39	NS	15
Post-test (mm)	62.7 ± 7.8	64.3 ± 5.7	59.5 ± 6.5	62.3 ± 6.5	0.23	3,39	NS	15
Sleep questionnaire
Time before asleep (min)	22.9 ± 7.1	22.3 ± 6.8	14.6 ± 3.1	14.4 ± 2.1	1.14	3,39	NS	15
Number of awakenings	0.8 ± 0.3	0.7 ± 0.3	0.7 ± 0.2	1.3 ± 0.4	1.46	3,39	NS	15
Sleep (h)	7.2 ± 0.2	7.4 ± 0.2	7.5 ± 0.2	7.3 ± 0.3	0.36	3,39	NS	15
Number of complaints	1.9 ± 0.7	2.6 ± 1.0	1.5 ± 0.4	1.8 ± 0.6	0.60	3,39	NS	15

Abbreviations are as indicated in Table 1 Significant drug–placebo differences are indicated by.

^aP < 0.017;

^bP < 0.025. High scores on the subjective driving quality indicate better driving performance.