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BCS70 – Child of CM (Multi-Age) – BAS Early Number Concepts

The 1970 British Cohort Study (BCS70) assessed the children of cohort members (CMs) during the study’s age 34 sweep using the Early Number Concepts measure from the British Ability Scales (BAS).

When the CM was aged 34, child assessments were conducted with the cohort member’s children. Each of the CM’s eligible children were asked to complete three exercises designed to measure a range of verbal and numerical abilities. Although dependent on the child’s age and abilities, each set of exercises was expected to take an average of 20 minutes to complete.

The BAS Early Number Concepts measure was administered as part of a set of ‘Early Years’ exercises (for children aged between 3 and 5 years and 11 months). Details on this measure and the data collected are outlined in the table below.


Domain:Pictorial reasoning
Measures:Verbal and visuo-spatial processing:
Knowledge of numerical and pre-numerical concepts
Verbal comprehension
Knowledge of basic language concepts
Visual perception and analysis of pictures
Integration of visual and conceptual information
CHC:Gf (Fluid ability)
Administrative method:Pointing or counting in response to plastic tiles. And responses to colour pictures in a booklet. Recorded by interviewer on CAPI.
Procedure:The child answered questions about number, size, or other numerical concepts. Stimuli used for the exercises included ten green plastic tiles and a series of pictures presented to the child. There were different starting and stopping points dependent upon age and performance. Starting and stopping points based on different ages and performance. These 'rules' were programmed into the computer to minimise the decisions interviewers had to make on the spot.
Link to questionnaire:https://cls.ucl.ac.uk/wp-content/uploads/2017/07/BCS70-2004-Guide-to-Child-Assessments.pdf (opens in new tab)
Scoring:30 questions in total. Starting and stopping item depends on age and performance. Score 1=correct, 2=incorrect, except item 3 (counting tiles) score 0 -6
Item-level variable(s):basenc01 - basenc30
Total score/derived variable(s):basencR (raw score)
basencA (ability and age adjusted)
Age of child (months):Mean = 53.95, SD = 10.56, Range = 36 - 71
Descriptives:basencR (raw score)basencA (ability and age adjusted)
N1,2261,226
Range0 - 2610 - 185
Mean15.33124.39
SD5.4126.47
(click image to enlarge)
(click image to enlarge)
Other sweep and/or cohort:None
Source:Elliott, C. D., Smith, P., & McCulloch, K. (1996). British Ability Scales Second Edition (BAS II). Administration and Scoring Manual. London: Nelson.
Elliott, C. D., Smith, P., & McCulloch, K. (1997). British Ability Scales Second Edition (BAS II). Technical Manual. London: Nelson.
Technical resources:Parsons, S., Bynner, J., & Foudouli, V. (2005). Measuring basic skills for longitudinal study: the design and development of instruments for use with cohort members in the age 34 follow-up in the 1970 British Cohort Study. NRDC: London
Parsons, S. (2006). British Cohort Study 2004 Follow up: Guide to Child Assessment Data, CLS Working Paper.
Reference examples:Cooksey, E., Joshi, H., & Verropoulou, G. (2009). Does mothers' employment affect children's development? Evidence from the children of the British 1970 Birth Cohort and the American NLSY79. Longitudinal and Life Course Studies, 1(1), 95-115.
Crawford, C., Goodman, A., & Joyce, R. (2011). Explaining the socio-economic gradient in child outcomes: the inter-generational transmission of cognitive skills. Longitudinal and Life Course Studies, 2(1), 77-93.
de Coulon, A., Meschi, E., & Vignoles, A. (2011). Parents' skills and children's cognitive and non-cognitive outcomes. Education Economics, 19(5), 451-474.
Mallows, D. (2013). The intergenerational transfer of numeracy skills. Institute of Education, University of London.

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This page is part of CLOSER’s ‘A guide to the cognitive measures in five British birth cohort studies’.