**Core Concept**
In emergency medicine, timely assessment and management of patients with self-harm and suicidal intent are crucial to prevent further harm. A multidisciplinary approach involving specialists from psychiatry, emergency medicine, and other relevant fields is essential. The decision to refer a patient for specialist assessment depends on the severity and complexity of the case.

**Why the Correct Answer is Right**
Immediate specialist assessment is warranted for patients with self-harm and suicidal intent, especially if they have a history of psychiatric disorders, previous attempts, or severe symptoms. However, not all cases require immediate specialist assessment. For instance, patients with stable psychiatric conditions, who are on regular treatment, and have no history of violent behavior or previous attempts, may not require immediate specialist assessment. In such cases, a thorough evaluation by the emergency department team and follow-up with the patient's primary care physician or a psychiatrist may be sufficient.

**Why Each Wrong Option is Incorrect**
**Option A:** This option is incorrect as patients with a history of psychiatric disorders, previous attempts, or severe symptoms require immediate specialist assessment.
**Option B:** This option is incorrect as patients with self-harm and suicidal intent, especially those with a history of violent behavior, require immediate specialist assessment.
**Option C:** This option is incorrect as patients with self-harm and suicidal intent, especially those with a history of previous attempts, require immediate specialist assessment.

**Clinical Pearl / High-Yield Fact**
Patients with self-harm and suicidal intent should be assessed using a standardized tool, such as the Columbia-Suicide Severity Rating Scale (C-SSRS), to evaluate the severity of their symptoms and identify those who require immediate specialist assessment.

**Correct Answer:** D.