Table 1.

Summary of MDMA and dexamphetamine effects on primary and secondary driving parameters (improvement, neutral, or impairment), as well as subjective measures of arousal or sleep

	MDMA–sleep deprivation study			Dexamphetamine–sleep deprivation study
	(Bosker et al. 2012)			(Hjalmdahl et al. 2012)
	MDMA	Sleep deprivation	MDMA + sleep deprivation	Dexamphetamine	Sleep deprivation	Dexamphetamine + sleep deprivation
Road tracking	No effect^a	Increased SDLP^b	Increased SDLP^b	No effect^a	Increased SDLP^b	Increased SDLP^c
Road tracking	No effect^a	Impairment > BAC 0.8 mg/mL^b	Impairment > BAC 0.8 mg/mL^b	No effect^a	Impairment > BAC 0.5 mg/mL SDLP^b	Relevance of impairment undecided (95 % CI drug effect includes BAC 0.5 mg/mL as well as 0)^c
Car following	No effect^a	No effect^a	No effect^a	Dose-related improvement of phase delay^a	Impairment of phase delay^b	Impairment of phase delay^b
Risk taking	Not assessed	Not assessed	Not assessed	Improvement RT to crossing cars^a	Improvement RT to crossing cars^a	Improvement RT to crossing cars^a
Laboratory measures of skills related to driving	Neutral on most measures^a	Impairment of attention and impulse control^b	Impairment of attention and impulse control^b	Not assessed	Not assessed	Not assessed
Laboratory measures of skills related to driving	Improvement on rapid information processing^a	Impairment of attention and impulse control^b	Impairment of attention and impulse control^b	Not assessed	Not assessed	Not assessed
Subjective measures	Increased arousal^a	Decreased arousal^b	Decreased arousal^b	Decreased sleepiness^a	Increased sleepiness^b	Increased sleepiness^b

RT reaction time

^aNeutral effects or “stimulating effects”

^b“Impairing” effects

^cImpairments associated with a wide 95 % CI, which indicate a large variety in response; some subjects are as impaired as under alcohol, and others perform as under placebo