Table 2.

Tabular overview of the study time schedule including assessments and visits

Time-point	T-2	T-1	T0	T1	T2	T3	T4
Pre-screening
Informed consent for pre-screening	X
SAGE	X
PD-CFRS	X			X	X	X	X
MRI safety screening	X
Alcohol abuse screening (CAGE-AID)	X
Eligibility screening
Montreal Cognitive Assessment		X		X	X	X	X
ICD diagnostic criteria		X		X
SAPS-PD†		X
Beck depression inventory		X		X	X	X	X
Hoehn & Yahr stage		X				X	X
Enrolment and allocation			X
Intervention
Cognitive training			←→
Active control condition			←→
Assessments
Neuropsychological assessment
1	Tower of London		X	X	X	X	X
	Montreal Cognitive Assessmenta			X	X	X	X
	Pentagon copy		X	X	X	X	X
1/2	Stroop Color Word Test		X	X	X	X	X
1	COWAT (‘letter fluency’) a		X	X	X	X	X
2	WAIS-III digit span		X	X	X	X	X
3	Rey Auditory Verbal Learning Testb		X	X	X	X	X
3	Location Learning Testc		X	X	X	X	X
4	Boston naming test		X	X	X	X	X
4	Category fluency		X	X	X	X	X
5	Rey Complex Figure Test		X	X	X	X	X
5	Visual Form Discrimination Test		X	X	X	X	X
Questionnaires and interviews
	CFQ		X	X	X	X	X
	Apathy scale		X	X	X	X	X
	Parkinson anxiety scale		X	X	X	X	X
	QUIP-RS		X	X	X	X	X
	NZPAQ-SF		X	X	X	X	X
	Credibility/expectancy questionnaire		X
Motor symptom assessments
	UPDRS-III - motor score		X			X	X
Medication use
	Levodopa equivalent daily dosage		X	X	X	X	X
Neuroimaging*
	MP-RAGE		X	X
	3D PSIR		X	X
	fMRI - resting state		X	X
	DTI		X	X

Cognitive domains: ¹Executive functioning, ²Attention and working memory, ³Memory, ⁴Language, ⁵Visuospatial. Abbreviations: CFQ Cognitive Failures Questionnaire, COWAT Controlled Oral Word Association Test, DTI diffusion tensor imaging, MP RAGE magnetization-prepared 180 degrees radio-frequency pulses and rapid gradient-echo; (f) MRI (functional) magnetic resonance imaging, NZPAQ-SF New Zealand Physical Activity Questionnaire – Short Form, PD-CFRS Parkinson’s Disease – Cognitive Functional Rating Scale, PSIR phase-sensitive inversion recovery, QPE Questionnaire for Psychotic Experiences, QUIP-RS Questionnaire for Impulsive-Compulsive Disorders in Parkinson’s Disease – Rating Scale, SAPS-PD Scale for Assessment of Positive Symptoms for Parkinson’s disease, UPDRS Unified Parkinson’s Disease Rating Scale, WAIS Wechsler Adult Intelligence Scale

An overview of cognitive assessments and questionnaires, including references is provided in additional file 1

*in a subsample of N = 80

Parallel forms of the same test are used at consecutive visits if available: ^aThree parallel forms; ^bTwo parallel forms; ^cOne parallel form