Cartton is 70 years old and has recently lost his wife and his best male friend within the past 3 months. His daughter brings him to the clinic because he has become forgetful, is not eating, has been sleeping poorly, and is frequently complaining of many aches and pains. Which assessment instrument would be most helpful at this time, considering his symptom presentation?

Reasoning: Choice A reason: The Delirium Rating Scale is a clinician-rated instrument specifically designed to measure the severity of delirium symptoms. While the patient exhibits forgetfulness, his clinical presentation of recent bereavement, anorexia, and insomnia more strongly suggests a mood disorder rather than the acute cognitive fluctuations and clouded consciousness typical of delirium. Choice B reason: The Confusion Assessment Instrument (CAM) is a standardized evidence-based tool used specifically to identify the presence of delirium in clinical settings. It focuses on acute onset, inattention, and disorganized thinking. Cartton's symptoms of somatic complaints and sleep disturbances following significant loss are more indicative of pseudodementia related to depression. Choice C reason: The Mini Mental Status Exam (MMSE) is a 30-point questionnaire used to measure cognitive impairment and screen for dementia. Although it assesses memory, it does not differentiate well between primary cognitive decline and cognitive deficits secondary to clinical depression, which is highly suspected given the patient's recent multiple bereavement. Choice D reason: The Geriatric Depression Scale is the most appropriate tool because Cartton’s symptoms of forgetfulness, anorexia, insomnia, and somatic aches following the death of his wife and friend are classic indicators of geriatric depression. This scale is specifically validated for older adults to distinguish between depression and primary dementia.