Mental Health

Screening & Assessment - Delirium, Dementia & Depression

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Deterioration Cognitive Observee (DECO)

The DECO questionnaire is to be completed by a person, such as a family member, who has had at least monthly contact with the client for the last 3 years.

A. Instruct the person who is completing the form to:

  • Consider how their relative was a year ago. Explain that the questions they are answering relate to everyday situations – the decisions are based on what they know about the person who is suspected of having an illness that has affected how the person is thinking and behaving.
  • Direct the person filling out the form to indicate their answers as either: Better or about the same (2), Not as well (1), Much worse (0).

B. Scoring the form:

  • The total score may range from 0 (indicates considerable change) to 38 (indicates no change).
  • A score of less than 30 indicates high likelihood of dementia and warrants further investigation and referral.

Practice Recommendations

The following diagram outlines the flow of information and recommendations that are included in this guideline. Adapted with permission from Registered Nurses Association of Ontario, Nursing Best Practice Guideline: Screening for Delirium, Dementia and Depression in Older Adults, November, 2003.

1. Family informant is defined as a person having had at least monthly

The Screening Assessment Flow Diagram for Delirium, Dementia and Depression

You should not rely on this pocket tool for financial or legal advice. It provides general information only. NICE is not responsible for any use of the information other than for general educational/informational purposes and no claim can be made against NICE or any of its personnel for any such use.
National Initiative for the Care of the Elderly (NICE)
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