title: The Symbol Digit Modalities Test: Normative data from a large nationally representative sample of Australians.
abstract: Data from the Household, Income and Labour Dynamics in Australia (HILDA) Survey were used to calculate weighted norms for the written version of the Symbol Digits Modalities Test (SDMT) by gender, 5-year age groups and four levels of educational attainment. The sample comprised 14,456 Australians (47% male; age range 15-100), of whom 25% reported a tertiary qualification, 30% reported a technical qualification (diploma or trade certificate), 16% reported completing Year 12 (final year of high school), and 29% reported their highest level of educational attainment to be Year 11 or below. Participants were excluded if they reported physical or neurological conditions that limited performance. Age, gender, and education were all significantly associated with SDMT performance, as was poor health, and cultural background. The reported norms are of greater scope and precision than previously available and have utility in a range of clinical and research settings. Indeed, normative data for the SDMT that are representative of a national population have not previously been published.
authors.affiliation: Centre for Research on Ageing Health and Wellbeing, The Australian National University, Canberra 2601, Australia kim.kiely@anu.edu.au.
authors.forename: Kim M
authors.initials: KM
authors.lastname: Kiely
authors.affiliation: Centre for Research on Ageing Health and Wellbeing, The Australian National University, Canberra 2601, Australia.
authors.forename: Peter
authors.initials: P
authors.lastname: Butterworth
authors.affiliation: Melbourne Institute of Applied Economic and Social Research, University of Melbourne, Melbourne 3010, Australia.
authors.forename: Nicole
authors.initials: N
authors.lastname: Watson
authors.affiliation: Melbourne Institute of Applied Economic and Social Research, University of Melbourne, Melbourne 3010, Australia.
authors.forename: Mark
authors.initials: M
authors.lastname: Wooden
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001315:Australia / Q000453:epidemiology; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009483:Neuropsychological Tests / Q000706:statistics & numerical data*; D011597:Psychomotor Performance / Q000502:physiology*; D012016:Reference Values; D055815:Young Adult
keywords: Aging; Assessment; Norms; Processing speed; Symbol Digit Modalities Test