Table 1.

Search strategy for the first search

	(1) Output	(2) Construct	(3) Population
Search terms	Assessment instruments	Dementia	Intellectual disability
Synonyms	assessment; diagnostic; diagnosis; screening; instrument; tool; measurement; questionnaire; psychometrics; scale; interview	dementia; Alzheimer’s disease	Intellectual disability; learning disability; intellectual developmental disorder; trisomy 21, Down syndrome
Combined and truncated	assess* OR diagnosti* OR screen OR screening* OR instrument* OR tool* OR measure* OR questionnaire* OR psychometr* OR scale* OR interview*	dement* OR Alzheimer*	((intellectual* OR learning) AND disab*) OR (intellectual* AND developmental* AND disorder*) OR trisom* 21 OR (down* AND syndrom*)
Example search string for Scopus	TITLE-ABS-KEY ((assess* OR diagnosti* OR screen OR screening* OR instrument* OR tool* OR measure* OR questionnaire* OR psychometr* OR scale* OR interview*) AND (dement* OR alzheimer*) AND (((intellectual* OR learning) AND disab*) OR (intellectual* AND developmental* AND disorder*) OR trisom* 21 OR (down* AND syndrom*))) AND PUBYEAR >2011