Characterising omission errors in everyday task completion and cognitive correlates in individuals with mild cognitive impairment and dementia

ABSTRACT

Objective: Functional ability declines with age and cognitive impairment. This study investigated errors of omission made by community-dwelling older adults completing everyday tasks in a naturalistic setting.

Method: Sixty-five cognitively healthy older adults (HOA), 19 individuals with single domain mild cognitive impairment (sdMCI), 33 individuals with multi-domain MCI (mdMCI), and 13 individuals with dementia completed measures of memory, processing speed, working memory, and executive functioning, as well as eight different activities of daily living in a naturalistic environment. Task steps were divided into preparatory, action-oriented, and concluding steps.

Results: For action-oriented steps, the number of omission errors increased with level of cognitive impairment beyond sdMCI (i.e., HOA = sdMCI < mdMCI < dementia). In contrast, for preparatory and concluding steps, the dementia group committed more omission errors than the HOA, sdMCI, and mdMCI groups, which did not differ.

Conclusions: The results suggest that the more complex and integrative action-oriented steps may be the first type of everyday task step to be affected in the process of cognitive decline, with preparatory and concluding steps being preserved longer and only showing decline in later stages of impairment (i.e., dementia). Individuals with sdMCI may use other intact abilities to compensate for task omission errors.

KEYWORDS:

• Activities of daily living
• memory
• executive function
• ageing
• functional status
• instrumental activities of daily living

Acknowledgements

We thank Chad Sanders, Alyssa Weakley, and Jennifer Walker for their assistance in coordinating data collection. We also thank members of the Aging and Dementia laboratory for their help in collecting and scoring the data.

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

This study was partially supported by the Life Science Discovery Fund of Washington State; National Institute of Biomedical Imaging and Bioengineering under Grant #R01 EB009675; and National Institute on Aging under Grant #R25 AG046114, which provided a summer fellowship to Mary Boege, who we would like to thank for her assistance with data coding.