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The inclusion of individuals with incipient dementia in normative data contaminates the distinction between normal and pathological aging. Conventional and Robust (excluding persons with incipient dementia) norms were created using data from the Canadian Study of Health and Aging (CSHA). Robust norms were not significantly better at distinguishing between normal and pathological aging. Norms reflecting the relationship between age and the prevalence of dementia revealed a probability of dementia of less than 35%. The results of the norming procedure serve to illustrate the validity of our current measures and methods for identifying cognitive impairment. CSHA Conventional norms are adequate for the identification of cognitive impairment. [ABSTRACT FROM AUTHOR]

Objective: Creation of normative data with regression corrections for demographic covariates reduces risk of small cell sizes compared with traditional normative approaches. We explored whether methods of correcting for demographic covariates (e.g., full regression models versus hybrid models with stratification and regression) and choice of covariates (i.e., correcting for age with or without sex and/or education correction) impacted reliability and validity of normative data. Method: Measurement invariance for sex and education was explored in a brief telephone-administered cognitive battery from the Canadian Longitudinal Study on Aging (CLSA; after excluding persons with neurological conditions N  = 12,350 responded in English and N  = 1,760 in French). Results: Measurement invariance was supported in hybrid normative models where different age-based regression models were created for groups based on sex and education level. Measurement invariance was not supported in full regression models where age, sex, and education were simultaneous predictors. Evidence for reliability was demonstrated by precision defined as the 95% inter-percentile range of the 5 th percentile. Precision was higher for full regression models than for hybrid models but with negligible differences in precision for the larger English sample. Conclusions: We present normative data for a remotely administered brief neuropsychological battery that best mitigates measurement bias and are precise. In the smaller French speaking sample, only one model reduced measurement bias, but its estimates were less precise, underscoring the need for large sample sizes when creating normative data. The resulting normative data are appended in a syntax file.

Objective: We present descriptive information on the cognitive measures used in the Canadian Longitudinal Study on Aging (CLSA) Comprehensive Cohort, relate this to information on these measures in the extant literature, and identify key considerations for their use in research and clinical practice. Method: The CLSA Comprehensive Cohort is composed of 30,097 participants aged 45-85   years at baseline who provided a broad range of sociodemographic, physical, social, and psychological health information via questionnaire and took part in detailed physical and cognitive assessments. Cognitive measures included: the Rey Auditory Verbal Learning Test - immediate and 5-min delayed recall, Animal Fluency, Mental Alternation Test (MAT), Controlled Oral Word Association Test (COWAT), Stroop Test - Victoria Version, Miami Prospective Memory Test (MPMT), and a Choice Reaction Time (CRT) task. Results: CLSA Comprehensive Cohort sample sizes were far larger than previous studies, and performances on the cognitive measures were similar to comparable groups. Within the CLSA Comprehensive Cohort, main effects of age were observed for all cognitive measures, and main effects of language were observed for all measures except the CRT. Interaction effects (language × age) were observed for the MAT, MPMT Event-based score, all time scores on the Stroop Test, and most COWAT scores. Main effects of education were observed for all measures except for the MPMT Time score in the French sample, and interaction effects (age × education) were observed for the RAVLT (immediate and delayed) for the English sample and the Stroop Dot time for the French sample. Conclusion: This examination of the cognitive measures used in the CLSA Comprehensive Cohort lends support to their use in large studies of health and aging. We propose further exploration of the cognitive measures within the CLSA to make this information relevant to and available for clinical practice.

Objective: The aim of this study was to verify the effect of age, education and sex on Miami Prospective Memory Test (MPMT) performance obtained at baseline of the Canadian Longitudinal Study on Aging (CLSA) by neurologically healthy French- and English-speaking subsamples of participants (N = 18,511)., Method: The CLSA is a nation-wide large epidemiological study with participants aged 45-85 years old at baseline. The MPMT is an event- and time-based measure of prospective memory, with scores of intention, accuracy and need for reminders, administered as part of the Comprehensive data collection. Participants who did not self-report any conditions that could impact cognition were selected, which resulted in 15,103 English- and 3408 French-speaking participants. The samples are stratified according to four levels of education and four age groups (45-54; 55-64; 65-74; 75+)., Results: There is a significant age effect for English- and French-speaking participants on the Event-based, Time-based, and Event- + Time-based scores of the MPMT. The effect of the education level was also demonstrated on the three MPMT scores in the English-speaking group. The score 'Intention to perform' was the most sensitive to the effect of age in both the English and French samples. Sex had no impact on performance on the MPMT., Conclusions: This study confirms the impact of age and level of education on this new prospective memory task. It informs future research with this measure including the development of normative data in French- and English-speaking Canadians on the Event-based and Time-based MPMT.

Objective: We detail a new approach to the creation of normative data for neuropsychological tests. The traditional approach to normative data creation is to make demographic adjustments based on observations of correlations between single neuropsychological tests and selected demographic variables. We argue, however, that this does not describe the implications for clinical practice, such as increased likelihood of misclassification of cognitive impairment, nor does it elucidate the impact on decision-making with a neuropsychological battery., Method: We propose base rate analyses; specifically, differential base rates of impaired scores between theoretical and actual base rates as the basis for decisions to create demographic adjustments within normative data. Differential base rates empirically describe the potential clinical implications of failing to create an appropriate normative group. We demonstrate this approach with data from a short telephone-administered neuropsychological battery given to a large, neurologically healthy sample aged 45-85 years old. We explored whether adjustments for age and medical conditions were warranted based on differential base rates of spuriously impaired scores., Conclusions: Theoretical base rates underestimated the frequency of impaired scores in older adults and overestimated the frequency of impaired scores in younger adults, providing an evidence base for the creation of age-corrected normative data. In contrast, the number of medical conditions (numerous cardiovascular, hormonal, and metabolic conditions) was not related to differential base rates of impaired scores. Despite a small correlation between number of medical conditions and each neuropsychological variable, normative adjustments for number of medical conditions does not appear warranted. Implications for creation of normative data are discussed.

Objective: We describe the implementation of cognitive measures within the Canadian Longitudinal Study on Aging (CLSA), a nationwide, epidemiological study of aging, and relate CLSA Tracking cohort data (n over 20,000) to previous studies using these measures., Method: CLSA participants (aged 45-85, n over 50,000) provided demographic, social, physical/clinical, psychological, economic, and health service utilization information relevant to health and aging through telephone interviews (Tracking cohort, n over 20,000) or in-person (i.e. Comprehensive cohort, n over 30,000) in both official languages (i.e. English, French). Cognitive measures included: the Rey Auditory Verbal Learning Test (RAVLT) - Trial 1 and five-minute delayed recall; Animal Fluency (AF), the Mental Alternation Test (MAT) (both cohorts); Controlled Oral Word Association Test, Stroop Test, Prospective Memory Test, and Choice reaction times (Comprehensive Cohort)., Results: Performance on the RAVLT Trial 1 and AF were very similar to comparable groups studied previously; CLSA sample sizes were far larger. Within the CLSA Tracking cohort, main effects of age and language were observed for all cognitive measures except RAVLT delayed recall. Interaction effects (language × age) were observed for AF., Conclusion: This preliminary examination of the CLSA Tracking cognitive measures lends support to their use in large studies of aging. The CLSA has the potential to provide the 'best' comparison data for adult Canadians generated to date and may also be applicable more broadly. Future studies examining relations among the psychological, biological, health, lifestyle, and social measures within the CLSA will make unique contributions to understanding aging.

Identification of persons at risk for developing dementia is of increasing importance as the proportion of persons over the age of 65 years grows globally. This review examines the neuropsychological literature specifically addressing the concept of impaired cognitive functioning of insufficient magnitude to warrant a diagnosis of dementia and its meaning with respect to the development of dementia. Although the most obvious finding in the literature is that persons with impaired cognitive functioning have varied outcomes, it is clear that a significant proportion of persons with mild cognitive impairment progress to dementia over a 1- to 2-year interval and approximately 50% progress to dementia by 5 years. The best and most commonly identified predictors of decline to dementia include age and lower baseline performance on neuropsychological measures (e.g., measures of memory). In discussing these findings, issues related to sample definition, sample selection, and methodology are identified and recommendations for future research are provided.