An evidence-based method for examining and reporting cognitive processes in nutrition research

Abstract

Cognitive outcomes are frequently implemented as endpoints in nutrition research. To reduce the number of statistical comparisons it is commonplace for nutrition researchers to combine cognitive test results into a smaller number of broad cognitive abilities. However, there is a clear lack of understanding and consensus as to how best execute this practice. The present paper reviews contemporary models of human cognition and proposes a standardised, evidence-based method for grouping cognitive test data into broader cognitive abilities. Both Carroll's model of human cognitive ability and the Cattell -Horn -Carroll (CHC) model of intelligence provide empirically based taxonomies of human cognition. These models provide a cognitive 'map' that can be used to guide the handling and analysis of cognitive outcomes in nutrition research. Making use of a valid cognitive nomenclature can provide the field of clinical nutrition with a common cognitive language enabling efficient comparisons of cognitive outcomes across studies. This will make it easier for researchers, policymakers and readers to interpret and compare cognitive outcomes for different interventions. Using an empirically derived cognitive nomenclature to guide the creation of cognitive composite scores will ensure that cognitive endpoints are theoretically valid and meaningful. This will increase the generalisability of trial results to the general population. The present review also discusses how the CHC model of cognition can also guide the synthesis of cognitive outcomes in systematic reviews and meta-analysis.

Effect of resveratrol supplementation on cognitive performance and mood in adults: a systematic literature review and meta-analysis of randomized controlled trials

“…Due to the range of cognitive function tests used in the included studies, the Cattall-Horn-Carroll cognitive framework was used to group differing cognitive function tests based on the frameworks proposed broad cognitive abilities and as used in previous nutraceutical trials. 29 When interventions and associated outcomes were assessed as sufficiently homogeneous, and when sufficient information was available from the studies, quantitative data were pooled into Review Manager (Version 5.3, The Cochrane Collaboration 2014) for meta-analysis. To calculate the overall treatment effect, the difference between the intervention and comparison groups' change scores from baseline to the end of follow-up was extracted.…”

Reduced inattention and hyperactivity and improved cognition after marine oil extract (PCSO-524®) supplementation in children and adolescents with clinical and subclinical symptoms of attention-deficit hyperactivity disorder (ADHD): a randomised, double-blind, placebo-controlled trial

“…Cognitive changes across different intervention studies are often difficult to compare with different measures often used. A recent approach to better understand the cognitive domains measured by different tests has been suggested by Pase and Stough (2014), who have advocated for the use of the Cattell-Horn-Carroll (CHC) cognitive framework for interventions. Future studies should use the CHC as a method to understand which cognitive domains have been tested from study to study.…”

The Moo’D Study: protocol for a randomised controlled trial of A2 beta-casein only versus conventional dairy products in women with low mood

“…The four tasks comprising the Cogstate Brief battery, from which main outcome variables will be analysed: Working Memory (One Back); Visual Learning (One Card); Psychomotor Function (Detection); and Attention (Identification). Additionally, the Paired Associate Learning (Continuous Paired Associate Learning) will be used as a measure of memory processes relating to encoding and retrieval [45,46]. Both measures have acceptable construct and criterion validity in a neuropsychological context [47].…”