There are a number of tools for assessing dementia and categorizing its phases. However, the Clinical Dementia Rating (CDR) system, an evaluation tool that can be used to determine how severe one’s dementia is, has recently been deemed one, if not the most, reliable of these techniques. Adding to its value, effective versions have been developed in a number of languages. The system includes 5 stages, and each stage represents distinct performance criteria.
Stage 1: CDR-0 – No Impairment
People experience no impairment in their functioning if they are classified as being in Stage 1, scoring a 0 according to CDR.
Stage 2: CDR-0.5 – Questionable Impairment
A score of 0.5 on CDR indicates small impairments and the second stage of dementia. For those who score a 0.5, personal care is not an issue, but it may be difficult to solve complex problems. Social and work performance may have slipped slightly but not significantly.
Stage 3: CDR-1 – Mild Impairment
Mild impairment is represented by a CDR score of 1, which is the third stage of dementia. In this stage, all assessed areas are impacted. These areas include: memory, personal care, judgment, orientation, community, home, and hobbies. However, the changes are deemed mild. The specific deficits experienced during this third stage are largely short-term memory problems and disorientation. Habitual activities like cleaning the home and maintaining personal hygiene may begin to be noticeably affected during this stage.
Stage 4: CDR-2 – Moderate Impairment
The fourth stage of dementia is moderate impairment, and is indicated by a CDR score of 2. At this stage, care for the patient is needed. Short-term memory is more significantly impacted, and the patient becomes increasingly confused as they struggle to maintain orientation, not only with respect to location, but also with respect to time.
Stage 5: CDR-3 – Severe Impairment
Severe impairment occurs in stage 5 of dementia. Those at this stage score a 3 on the CDR. Extreme memory loss and disorientation are hallmarks of this, the most severe stage of dementia. At this point, they cannot function autonomously and must be closely monitored by another.
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