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BCS70 – Child of CM (Multi-Age) – BAS Spelling

The 1970 British Cohort Study (BCS70) assessed the children of cohort members (CMs) during the study’s age 34 sweep using the Spelling 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 Spelling measure was administered as part of a set of ‘School Age’ exercises (for children aged between 6 and 16 years and 11 months). Details on this measure and the data collected are outlined in the table below.


Domain:School knowledge - spelling (achievement scale)
Measures:Spelling achievement:
Visual memory for correct spelling of whole words
Knowledge of phoneme-to-grapheme mapping
Knowledge of spelling rules
CHC:Gc (Crystallised)
Grw (Reading/Writing)
Administrative method:Writing and speaking; interviewer enters onto CAPI
Procedure:All children within a defined age band received a fixed number of words. The child spells the word, then reads their answer to the interviewer, who enters correct or incorrect into CAPI. A stopping rule of 5 failures in a row was applied.
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:38 words in total, start and finish point based on age of child. Number of words varied by age:
age 6:0 - 6:11 15 words (1 - 15)
age 7:0 - 8:11 20 words (6 - 25)
age 9:0 - 10:11 20 words (11 - 30)
age 11:0 - 16:11 28 words (11 - 38)
Item-level variable(s):bassp01 - bassp15 (age 6:0 - 6:11)
bassp06 - bassp25 (age 7:0 - 8:11)
bassp11 - bassp30 (age 9:0 - 10:11)
bassp11-bassp38 (age 11:0 - 16:11)
Total score/derived variable(s):basspR (raw score)
bassp1hr (revised score - maximum of 100)
Age of participants (months):Mean = 117.71, SD = 32.97, Range = 72 - 203
Descriptives:basspR (raw score)bassp1hr (revised score - max. of 100)
N2,2482,248
Range0 - 280 - 100
Mean13.3459.91
SD5.5621.91
(click image to enlarge)
(click image to enlarge)
Other sweep and/or cohort:None
Source:Modified version (reduced number of words from 75 to 38 by using the first 5 in 10 of 7 blocks and 3 of 5 of the last block of BAS) of:
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: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.

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