Background: There is a need for feasible, scalable assessments to detect cognitive impairment and... more Background: There is a need for feasible, scalable assessments to detect cognitive impairment and decline. The Cogstate Brief Battery (CBB) is validated for Alzheimer’s disease (AD) and in unsupervised and bring your own device contexts. The CBB has shown usability for self-completion in the home but has not been employed in this way in a multisite clinical trial in AD. Objective: The objective of the pilot was to evaluate feasibility of at-home, self-completion of the CBB in the Alzheimer’s Disease Neuroimaging Initiative (ADNI) over 24 months. Methods: The CBB was included as a pilot for cognitively normal (CN) and mild cognitive impairment (MCI) participants in ADNI-2, invited to take the assessment in-clinic, then at at-home over a period of 24 months follow-up. Data were analyzed to explore acceptability/usability, concordance of in-clinic and at-home assessment, and validity. Results: Data were collected for 104 participants (46 CN, 51 MCI, and 7 AD) who consented to provide C...
The One Card Learning Test (OCL80) from the Cogstate Brief Battery has shown high sensitivity to ... more The One Card Learning Test (OCL80) from the Cogstate Brief Battery has shown high sensitivity to changes in memory in early Alzheimer’s disease (AD), although recent studies suggest that OCL sensitivity to memory impairment in symptomatic AD is not as strong as that for other standardized assessments of memory. This study aimed to improve the sensitivity of the OCL80 to AD-related memory impairment by reducing the test difficultly (i.e., OCL48). Experiment 1 showed performance in healthy adults improved on the OCL48 while the pattern separation operations that constrain performance on the OCL80 were retained. Experiment 2 showed repeated administration of the OCL48 at short retest intervals did not induce ceiling or practice effects. Experiment 3 showed that the sensitivity of the OCL48 to AD-related memory impairment (Glass’s ∆ = 3.11) was much greater than the sensitivity of the OCL80 (Glass’s ∆ = 1.94). Experiment 4 used data from a large group of cognitively normal older adults ...
An evolving paradigm shift in the diagnostic conceptualization of Alzheimer's disease is refl... more An evolving paradigm shift in the diagnostic conceptualization of Alzheimer's disease is reflected in its recently updated diagnostic criteria from the National Institute on Aging-Alzheimer's Association and the International Working Group. Additionally, it is reflected in the increased focus in this field on conducting prevention trials in addition to improving cognition and function in people with dementia. These developments are making key contributions towards defining new regulatory thinking around Alzheimer's disease treatment earlier in the disease continuum. As a result, the field as a whole is now concentrated on exploring the next-generation of cognitive and functional outcome measures that will support clinical trials focused on treating the slow slide into cognitive and functional impairment. With this backdrop, the International Society for CNS Clinical Trials and Methodology convened semi-annual working group meetings which began in spring of 2012 to addres...
Journal of psychopharmacology (Oxford, England), Jun 23, 2016
The objective of this substudy was to examine the effect of desvenlafaxine 50 mg/day compared wit... more The objective of this substudy was to examine the effect of desvenlafaxine 50 mg/day compared with placebo on cognitive function in employed outpatients with major depressive disorder. A total of 11/55 (20%) study sites in a 12-week, randomized, double-blind, placebo-controlled trial administered cognitive assessments in memory, attention, and executive functioning domains using the cognitive drug research system. Changes from baseline were subjected to analysis of covariance with baseline levels as covariates, using last observation carried forward data. A significant improvement with desvenlafaxine 50 mg/day (n=52) compared with placebo (n=29) was observed on the quality of working memory composite measure (0.081 units (0.005, 0.156);P=0.0365) at last observation carried forward. Improvement from baseline on the speed of working memory composite was significant for desvenlafaxine (-226.6 msec (-316.7, -136.4);P<0.0001) and for placebo (-133.3 msec (-257.2, -9.4);P=0.0354); howe...
The study population comprised 432 females (mean age 57.6 years; range 18 to 86) and 456 males (m... more The study population comprised 432 females (mean age 57.6 years; range 18 to 86) and 456 males (mean age 60.6 years; range 18 to 88), diagnosed with either Hodgkin's disease, non-Hodgkin's lymphoma, chronic lymphocytic leukemia, or multiple myeloma. An ...
Background: There is a need for feasible, scalable assessments to detect cognitive impairment and... more Background: There is a need for feasible, scalable assessments to detect cognitive impairment and decline. The Cogstate Brief Battery (CBB) is validated for Alzheimer’s disease (AD) and in unsupervised and bring your own device contexts. The CBB has shown usability for self-completion in the home but has not been employed in this way in a multisite clinical trial in AD. Objective: The objective of the pilot was to evaluate feasibility of at-home, self-completion of the CBB in the Alzheimer’s Disease Neuroimaging Initiative (ADNI) over 24 months. Methods: The CBB was included as a pilot for cognitively normal (CN) and mild cognitive impairment (MCI) participants in ADNI-2, invited to take the assessment in-clinic, then at at-home over a period of 24 months follow-up. Data were analyzed to explore acceptability/usability, concordance of in-clinic and at-home assessment, and validity. Results: Data were collected for 104 participants (46 CN, 51 MCI, and 7 AD) who consented to provide C...
The One Card Learning Test (OCL80) from the Cogstate Brief Battery has shown high sensitivity to ... more The One Card Learning Test (OCL80) from the Cogstate Brief Battery has shown high sensitivity to changes in memory in early Alzheimer’s disease (AD), although recent studies suggest that OCL sensitivity to memory impairment in symptomatic AD is not as strong as that for other standardized assessments of memory. This study aimed to improve the sensitivity of the OCL80 to AD-related memory impairment by reducing the test difficultly (i.e., OCL48). Experiment 1 showed performance in healthy adults improved on the OCL48 while the pattern separation operations that constrain performance on the OCL80 were retained. Experiment 2 showed repeated administration of the OCL48 at short retest intervals did not induce ceiling or practice effects. Experiment 3 showed that the sensitivity of the OCL48 to AD-related memory impairment (Glass’s ∆ = 3.11) was much greater than the sensitivity of the OCL80 (Glass’s ∆ = 1.94). Experiment 4 used data from a large group of cognitively normal older adults ...
An evolving paradigm shift in the diagnostic conceptualization of Alzheimer's disease is refl... more An evolving paradigm shift in the diagnostic conceptualization of Alzheimer's disease is reflected in its recently updated diagnostic criteria from the National Institute on Aging-Alzheimer's Association and the International Working Group. Additionally, it is reflected in the increased focus in this field on conducting prevention trials in addition to improving cognition and function in people with dementia. These developments are making key contributions towards defining new regulatory thinking around Alzheimer's disease treatment earlier in the disease continuum. As a result, the field as a whole is now concentrated on exploring the next-generation of cognitive and functional outcome measures that will support clinical trials focused on treating the slow slide into cognitive and functional impairment. With this backdrop, the International Society for CNS Clinical Trials and Methodology convened semi-annual working group meetings which began in spring of 2012 to addres...
Journal of psychopharmacology (Oxford, England), Jun 23, 2016
The objective of this substudy was to examine the effect of desvenlafaxine 50 mg/day compared wit... more The objective of this substudy was to examine the effect of desvenlafaxine 50 mg/day compared with placebo on cognitive function in employed outpatients with major depressive disorder. A total of 11/55 (20%) study sites in a 12-week, randomized, double-blind, placebo-controlled trial administered cognitive assessments in memory, attention, and executive functioning domains using the cognitive drug research system. Changes from baseline were subjected to analysis of covariance with baseline levels as covariates, using last observation carried forward data. A significant improvement with desvenlafaxine 50 mg/day (n=52) compared with placebo (n=29) was observed on the quality of working memory composite measure (0.081 units (0.005, 0.156);P=0.0365) at last observation carried forward. Improvement from baseline on the speed of working memory composite was significant for desvenlafaxine (-226.6 msec (-316.7, -136.4);P<0.0001) and for placebo (-133.3 msec (-257.2, -9.4);P=0.0354); howe...
The study population comprised 432 females (mean age 57.6 years; range 18 to 86) and 456 males (m... more The study population comprised 432 females (mean age 57.6 years; range 18 to 86) and 456 males (mean age 60.6 years; range 18 to 88), diagnosed with either Hodgkin's disease, non-Hodgkin's lymphoma, chronic lymphocytic leukemia, or multiple myeloma. An ...
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