Carolien Zeetsen

31 CHAPTER Psychometric properties of the MoCA in healthy participants 2 Methods Design A repeated–measures within–subject design was used in which MoCA version 7.1 and one of the alternate versions 7.2 or 7.3 were administered, with an interval of two to four weeks. Data were collected between March 2012 and December 2016, as part of a larger research project on the applicability of the MoCA in addiction care. Participants The main inclusion criterion was an age between 18 and 70. Exclusion criteria were: 1) a current diagnosis of substance or behavioural abuse/dependence according to DSM–5 (APA, 2013) criteria, excluding nicotine; 2) self–reported presence or history of neurological disorders (e.g. stroke, dementia, traumatic brain injury, Korsakoff’s syndrome); 3) self– reported presence or history of an otherwise defined psychotic, psychiatric and/or medical condition that, in the view of this study, would interfere with administration of the MoCA and/or otherwise compromise participation. In total, 218 healthy participants were recruited, one of whom was excluded from further analyses for not meeting the inclusion criterion (i.e. aged 17). Of the remaining 217 participants, seven had completed MoCA version 7.2 and 7.3, and not MoCA version 7.1. As this group was too small to make reliable comparisons between these two alternate versions, these participants were also excluded. Participants were recruited via the personal network of the assessors, by contacting companies and associations, via mouth to mouth, or via social media. Materials Montreal Cognitive Assessment The authorised Dutch translations of three alternate versions of the MoCA were used in this study. MoCA version 7.1 was translated in 2010 by Dautzenberg and De Jonghe (Thissen et al., 2010) and MoCA alternate versions 7.2 and 7.3 were translated in 2012 by Wester and Kessels. The MoCA consists of 12 items: alternating trail making (0–1 point), figure copy (0–1 point), clock drawing (0–3 points), animal naming (0–3 points), digit span (0–2 points), sustained attention (0–1 point), serial subtraction (0–3 points), sentence repetition (0–2 points), verbal fluency (0–1 point), abstract reasoning (0–2 points), memory (delayed recall, 0–5 points) and orientation (0–6 points). All items add up to MoCA–TS, with a maximum of 30 points, where a higher score represents better cognitive functioning. In this study, the unadjusted raw MoCA–TS was used in all analyses (i.e. not adding points for individuals with lower educational levels). Seven Domain Scores (MoCA–DS) were calculated: executive functioning (alternating trail making and verbal fluency: 0–2 points), visuospatial abilities (figure copy and clock drawing: 0–4 points), attention,