Fundamental concept
Reasoning between competing explanations using pattern, timeline, course, and confounders rather than symptom matching.
Read: Differential Diagnosis and Case Formulation →Scenario
A 31-year-old reports two months of low mood, poor sleep, and loss of interest. He drinks six to eight beers most evenings and has done so for about a year.
Sort each finding by what it supports.
Items
Whether he has had any period of 30 days without alcohol recently
Mother treated for depression in her thirties
Whether the sleep problem is difficulty falling asleep or early waking
Mood is consistently worst on mornings after heavy drinking
Reports low mood during a six-month period two years ago when he was not drinking
Drinking escalated before the current low mood began
Supports independent depressive disorder
Drop items here
Supports substance-induced presentation
Drop items here
Still missing / must ask
Drop items here
