NSHD – Age 53 – Timed Letter Search/Letter Cancellation Test

Scoop.it ShareThis

The MRC National Survey of Health of Development (NSHD) assessed their cohort members (CMs) during the study’s age 53 sweep using the Timed Letter Search/Letter Cancellation Test.

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


Domain:Processing speed
Measures:Attention/concentration
Mental speed
Visual scanning
CHC:Gv (Visual Processing)
Gs (Processing Speed)
Administration method:Research nurse; face to face; pen and paper
Procedure:Similar to age 43, only 1 trial was given. Moreover, the letters covered a full page, so that a maximal score was obtained, which may have been restricted at age 43 due to the shorter blocks of letters.
Link to questionnaire:https://skylark.ucl.ac.uk/NSHD/lib/exe/fetch.php?media=questionnaires:1999-capi.pdf (opens in new tab)
Scoring:The number of hits, misses and row/column reached were recorded, meaning multiple scoring schemes are possible. Although there is no definitive scoring system used, the most widely adopted approach is to calculate speed (number of letters scanned) and accuracy (dividing the number of missed targets for each trial by the corresponding speed score).
Item-level variable(s):vscl99 - vsrw99
Total score/derived variable(s):CANSP99
Descriptives:Accuracy score
N = 2,932
Range = 64 - 591
Mean = 281.07
SD = 76.09
(click image to enlarge)
Age of participants (months):Mean = 641.47, SD = 2.09, Range = 636 - 650
Other sweep and/or cohort:NSHD – Age 43 – Timed Letter Search/Letter Cancellation Test (3 trials)
NSHD – Age 60-64 – Timed Letter Search/Letter Cancellation Test
NSHD – Age 68-70 – Timed Letter Search/Letter Cancellation Test
NCDS – Age 50 – Timed Letter Search/Letter Cancellation Test
NCDS – Age 61-63 – Proposed repeat of tests at age 50
BCS70 – Age 46-47 – Timed Letter Search/Letter Cancellation Test
Source:The letter cancellation test was adapted from the MRC Cognitive Function and Ageing Study (MRC CFA Study, 1998).
Technical resources:None
Reference examples:Richards, M., Kuh, D., Hardy, R., & Wadsworth, M. (1999). Lifetime cognitive function and timing of the natural menopause. Neurology, 53(2), 308-308.
Richards, M., Hardy, R., Kuh, D., & Wadsworth, M. E. (2001). Birth weight and cognitive function in the British 1946 birth cohort: longitudinal population based study. BMJ, 322(7280), 199-203.

Go to:


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