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ALSPAC – Age 18 months – Griffiths Scales of Mental Development (GSMD)

The Avon Longitudinal Study of Parents and Children (ALSPAC) assessed their cohort members (CMs) at 18 months’ age (Children in Focus Clinic) using the Griffiths Scales of Mental Development (GSMD).

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

Domain:Verbal and non-verbal ability
Measures:Verbal ability
Non-verbal/performance ability
Psychomotor Abilities
Personal/social skills
CHC:G (General ability)
Administration method:Trained interviewer; clinical setting; guided play, physical task, oral questions, pen and paper.
Procedure:The Griffiths Test consists of five subscales that assess the following areas of development: i) locomotion, ii) personal/social skills, iii) hearing and speech, iv) hand-eye coordination, and performance. The subscales consist of 86 items each. The first 48 items are designed for children aged 0 - 2 years, with the remaining 38 items belonging to the extension of the scale (6 additional items per year). Standardised developmental quotients (DQs) for each subscale are calculated using the formula: DQ = (Mental age x 100)/Chronological age. An overall DQ is calculated using the mean scores across all 5 scales. Due to time constraints, only the items pertaining to the 12-24 month period were administered when children were aged 18 months. Thus, study children who were considerably advanced/delayed may have received inflated/deflated scores respectively. The scales were administered by eight trained testers. Each of the five sub-tests is detailed in a separate section below. Duration: approximately 45 minutes for each full sub-test
Link to questionnaire: (opens in new tab)
Scoring:Standardised DQ (0 - 100)
Item-level variable(s):Not readily available
Total score/derived variable(s):cf772 - cf783
Descriptives:Age adjusted average development score
N = 1,390
Range = 64.91 - 130.37
Mean = 88.02
SD = 42.81
(click image to enlarge)
Age of participants:Mean = 79.90 weeks, SD = 1.47, Range = 76 - 87
Other sweep and/or cohort:None
Source:Griffiths, R. (1970). The abilities of young children. London: Child Development Research Centre.
Technical resources:None
Reference examples:Hibbeln, J. R., Davis, J. M., Steer, C., Emmett, P., Rogers, I., Williams, C., & Golding, J. (2007). Maternal seafood consumption in pregnancy and neurodevelopmental outcomes in childhood (ALSPAC study): an observational cohort study. The Lancet, 369(9561), 578-585.
Pearson, R. M., Heron, J., Melotti, R., Joinson, C., Stein, A., Ramchandani, P. G., & Evans, J. (2011). The association between observed non-verbal maternal responses at 12 months and later infant development at 18 months and IQ at 4 years: A longitudinal study. Infant Behavior and Development, 34(4), 525-533.

For the named items in the table above, links are provided (where applicable) to their corresponding content on CLOSER Discovery. Where a variable range is provided, full variable lists can be accessed through the ‘Variable Groups’ tab on the linked Discovery page.

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