Harmonisation of later-life cognitive function across national contexts: results from the Harmonized Cognitive Assessment Protocols.

Gross AL, Li C, Briceño EM, Arce Rentería M, Jones RN, Langa KM, Manly JJ, Nichols E, Weir D, Wong R, Berkman L, Lee J, Kobayashi LC. Harmonisation of later-life cognitive function across national contexts: results from the Harmonized Cognitive Assessment Protocols. The Lancet. Healthy longevity. 2023 Oct 1; 4(10):e573-e583.

Dimensions for VA is a web-based tool available to VA staff that enables detailed searches of published research and research projects.

If you have VA-Intranet access, click here for more information vaww.hsrd.research.va.gov/dimensions/

VA staff not currently on the VA network can access Dimensions by registering for an account using their VA email address.    Search Dimensions for VA for this citation
* Don't have VA-internal network access or a VA email address? Try searching the free-to-the-public version of Dimensions

Search for Abstract from PubMed

---

Abstract:

BACKGROUND: The Harmonized Cognitive Assessment Protocol (HCAP) is an innovative instrument for cross-national comparisons of later-life cognitive function, yet its suitability across diverse populations is unknown. We aimed to harmonise general and domain-specific cognitive scores from HCAP studies across six countries, and evaluate reliability and criterion validity of the resulting harmonised scores. METHODS: We statistically harmonised general and domain-specific cognitive function scores across publicly available HCAP partner studies in China, England, India, Mexico, South Africa, and the USA conducted between October, 2015 and January, 2020. Participants missing all cognitive test items in a given HCAP were excluded. We used an item banking approach that leveraged common cognitive test items across studies and tests that were unique to studies. We generated harmonised factor scores to represent a person''s relative functioning on the latent factors of general cognitive function, memory, executive function, orientation, and language using confirmatory factor analysis. We evaluated the marginal reliability, or precision, of the factor scores using test information plots. Criterion validity of factor scores was assessed by regressing the scores on age, gender, and educational attainment in a multivariable analysis adjusted for these characteristics. FINDINGS: We included 21?144 participants from the six HCAP studies of interest (11?480 women [54·3%] and 9664 [45·7%] men), with a median age of 69 years (IQR 64-76). Confirmatory factor analysis models of cognitive function in each country fit well: 31 (88·6%) of 35 models had adequate or good fit to the data (comparative fit index = 0·90, root mean square error of approximation = 0·08, and standardised root mean residual = 0·08). Marginal reliability of the harmonised general cognitive function factor was high ( > 0·9) for 19 044 (90·1%) of 21?144 participant scores across the six countries. Marginal reliability of the harmonised factor was above 0·85 for 19?281 (91·2%) of 21?142 participant factor scores for memory, 7805 (41·0%) of 19?015 scores for executive function, 3446 (16·3%) of 21?103 scores for orientation, and 4329 (20·5%) of 21?113 scores for language. In each country, general cognitive function scores were lower with older age and higher with greater levels of educational attainment. INTERPRETATION: We statistically harmonised cognitive function measures across six large population-based studies of cognitive ageing. These harmonised cognitive function scores empirically reflect comparable domains of cognitive function among older adults across the six countries, have high reliability, and are useful for population-based research. This work provides a foundation for international networks of researchers to make improved inferences and direct comparisons of cross-national associations of risk factors for cognitive outcomes in pooled analyses. FUNDING: US National Institute on Aging.