The 1958 National Child Development Study (NCDS) assessed the children of a sub-sample of cohort members (CMs) using the Peabody Picture Vocabulary Test Revised (PPVT-R).
The child assessments included in the NCDS5 Child Interview (conducted when the CM was aged 33) applied only to the natural or adopted children of CMs aged 3 years, 11 months, and 16 days or older. Some 3,575 (71 percent) of the cohort children identified were eligible for the Child Interview. The tests were based on those used by the US National Longitudinal Survey of Youth (NLSY) for their 1990 survey of the children of female respondents. These tests were developed in the US and a number of changes (mainly substituting terminology) were made to individual assessments for use in the NCDS.
Prior to administering these tests, the interviewer calculated the Peabody Picture Vocabulary Test (PPVT) age of the child (actual age rounded up or down to the nearest whole month) to establish, if the child was eligible for testing, which tests would be administered and, for some tests, the appropriate starting point of the test. Time at start and completion (24 hour clock) was calculated using the following variables: n520128 n520130 n521935 n521937.
The PPVT-R was administered if the child was aged 3 years, 11 months, and 16 days or older. Details on this measure and the data collected are outlined in the table below.
|CHC:||Gc (Crystallised intelligence)|
|Administrative method:||Interviewer at home; face to face; read and point at picture|
|Procedure:||The interviewer said a word and the child pointed to one of four pictures which best portrayed the meaning of the word. The difficulty level increased as the child goes through the test. The interviewer:|
|identified the start point (using the PPVT)|
|established basal (8 correct answers in a row) and ceiling (6 out of 8 responses wrong) points.|
|If the child did not get the first 8 items correct, then they worked backwards until 8 consecutive correct items were identified. If the child got back to item 1 then this became the basal. The ceiling was identified when 6 out of 8 items were incorrect or if item 175 was reached.|
|Link to questionnaire:||https://cls.ucl.ac.uk/wp-content/uploads/2017/07/Ncds5d.pdf (opens in new tab)|
|Scoring:||See source materials|
|Item-level variable(s):||n520132 (starting item)|
|n520135 - n520762 (items 1 - 175, correct and response)|
|n520813 (basal obtained Y/N)|
|n520814 (ceiling obtained Y/N)|
|n520124 n520126 (PPVT age in years and months)|
|Total score/derived variable(s):||No derived variables|
|Age of participant (months):||Mean = 103.31, SD = 36.89, Range = 47 - 224|
|Descriptives:||Not available (see technical resources on deriving scores)|
|Other sweep and/or cohort:||BCS70 – Age 5 – English Picture Vocabulary Test (EPVT)|
|BCS70 – Age 10 – Pictorial Language Comprehension Test (based on EPVT at age 5)|
|Source:||Dunn, L. & Dunn, L. (1981). PPVT-R Manual (Circle Pines, MN American Guidance Service)|
|Technical resources:||For further details see” BAKER P C and MOTT FL(1988) NLSY Child Handbook 1989 A Guide & Resource Document for the National Longitudinal Survey of Youth (1988) Child Data (Columbus, Ohio Center for Human Resource Research, The Ohio State University)|
|Reference examples:||Michael, R. (2003). Children’s cognitive skill development in Britain and the United States. International Journal of Behavioral Development, 27(5), 396-408.|
|Armstrong, A. (2012). Belief in a just world and children's cognitive scores. National Institute Economic Review, 222(1), R7-R19.|
|Parcel, T. L., & Campbell, L. A. (2017). Can the welfare state replace parents? Children's cognition in the United States and Great Britain. Social Science Research, 64, 79-95.|
- Overview of all cognitive measures in NCDS
- Overview of childhood cognitive measures across all studies
This page is part of CLOSER’s ‘A guide to the cognitive measures in five British birth cohort studies’.