Table 3. List of tests used for assessment of impulsivity, including brief description of the task, the available outcome measures, and the measures included in the principal components analysis.

Test Type	Test and reference	Brief description	Outcome measures or subscales	Principal measure included in PCA
1	Kirby Temporal DiscountingKirby and Marakovic [130]	Serial forced choice between two rewards, of varyingMagnitude and different time delays	k values	k
1	BIS Barrat Impulsivity ScaleStanford et al. [60],Barrat [131]	30 item self-report questionnaire3 second order factors of the impulsivity concept	1. Attentional Impulsiveness2. Motor Impulsiveness3. Nonplanning Impulsiveness	BIS score
1	Behavioural Inhibitory System Behavioural Approach System BIS/BAS, Carver [132]	Self-Report questionnaire	1._ BAS-Behavioural Approach System for appetitive motivation2._ BIS-Behavioural Avoidance System for aversive motivation	BAS scores
1	South Oaks Gambling Screening –SOCSLesieur and Blume [133]	Structured interview on different aspects of pathological gambling	Total score	na
1	Modified-Minnesota Impulsive Disorders Interview –MIDI, Grant [134]	Structured interview exploring different areas of impulsive, repetitive, explosive and compulsive sexual behaviour	Total score	na
2	Motor Go-NoGo task	“Action restraint” inhibition of a prepotent response in response to a low frequency visual cue	Commission errors on NoGo trialsOmission errors and RT on Go trials	Commission errors
2	Temporal interval estimation	Subjective estimation of short periods of time, producing 2, 5, 9 and 17 s intervals	Temporal scaling error (proportional)	Estimation error
2	Frontal Assessment Battery –FABDubois et al. [135]	Brief clinical assessment of frontal function.Items 4 and 5 asses motor inhibitory control	Total score on items 4–5	Total score
2	Stop-signal Task (CANTAB)	“Action cancellation” Stop signal response task.	Direction of error, percentage successful Stop trials, Go reaction time, Stop signal reaction time (SSRT)	SSRT
2	Cambridge Gambling Task (CANTAB)	Assesses decision-making and risk-taking behaviour within gambling context.	Delay aversion (difference between the risk-taking on descend and ascend conditions), Deliberation time, Quality of decision, Risk taking	Delay aversion
2	Hayling Sentence Completion TestBurgess [136]	Sentence completion	Total score, Scaled score	Total score
2	Stroop test, Stroop [137]	Colour-word conflict resolution (timed)	‘CW’ responses	Total score
3	Saccade NoGoPerneczky et al. [94]	Conditional reflexive horizontal saccades, to either go or no go.	For error rate, mean reciprocal RT, variances, and estimate of express saccades variance	Error rate

Type 1 tests are based on questionnaires or interview and self-reporting, Type 2 tests are behavioural response measures, for manual tasks. Type 3 indicates a saccadometric decision_task.