NCDS – Age 11 – General Ability Test (Verbal and Non-verbal)

The 1958 National Child Development Study (NCDS) assessed their cohort members (CMs) during the study’s age 11 sweep using the General Ability Test (Verbal and Non-verbal).

Details on this measure and the data collected from the CMs are outlined in the table below.

Year of data collection:	1969
Domain:	Verbal (reasoning)
	Non-verbal (reasoning)
Measures:	Measure of general ability, including verbal and non-verbal elements. Douglas (1964) claims the test correlates highly with IQ-type tests used for secondary school selection.
CHC:	G (General ability)
	Gc (Crystallised)
	Gf (Fluid)
CLOSER Source:	Explore this sweep in CLOSER Discovery: NCDS Age 11 Survey 1969 (opens in a new tab)
Administrative method:	Teacher at school; face to face; pen and paper
Procedure:	The test consisted of 80 multiple choice questions. Before the test was administered the child was shown four examples which the child and teacher completed together. For the verbal items the child was presented with an example set of four words that were linked either logically, semantically or phonologically; for the non-verbal test, fours example shapes or symbols were used. Next to the examples were three word or shapes/symbols with a blank, along with 5 response options to choose from. From the list, the child was required to underline the missing item which completed the sequence. Duration: 30 minutes
Link to questionnaire:	https://cls.ucl.ac.uk/wp-content/uploads/2017/07/NCDS2-Guide-to-the-Dataset.pdf (opens in new tab)
Scoring:	80 items in total; 40 verbal and 40 non-verbal. Each correct answer given 1 mark and 0 for incorrect answer. Total score ranges from 0 to 80, verbal and non-verbal subscales (0 to 40).
Item-level variable(s):	Not currently available
Total score/derived variable(s):	n914 (verbal); n917 (non-verbal); n920 (general ability)
Age of participant (months):	Mean = 134.25, SD = 1.70, Range = 130 – 152
Descriptives:		General ability	Verbal ability	Non-verbal ability
	N	14,131	14,131	14,131
	Range	0 – 80	0 – 40	0 – 40
	Mean	42.94	22.06	20.88
	SD	16.14	9.36	7.61
		(click image to enlarge)	(click image to enlarge)	(click image to enlarge)
Other sweep and/or cohort:	NSHD – Age 11 – General Ability Test (Verbal and Non Verbal)
Source:	Pigeon DA. Details of the fifteen years tests. Appendix 1 in Douglas, J.W.B., The Home and the School: A study of ability and attainment in the primary school. 1964, London: MacGibbon and Kee.
Technical resources:	Shepherd, P. Measures of ability at ages 7 to 16. National Child Development Study User Guide, 2012.
Example articles:	Galindo-Rueda, F., & Vignoles, A. (2005). The declining relative importance of ability in predicting educational attainment. Journal of Human Resources, 40(2), 335-353.
	Schoon, I., Cheng, H., Gale, C. R., Batty, G. D., & Deary, I. J. (2010). Social status, cognitive ability, and educational attainment as predictors of liberal social attitudes and political trust. Intelligence, 38(1), 144-150.