Anchor: Even if the assessment is embedded in a general health-needs survey, patients know they are being asked about alcohol, and that could affect their answers.
Entailed: Knowing they're being asked about alcohol, patients' answers could be affected. 
Contradiction: Patients are not asked about alcohol. 
Contradiction: The bride is wearing a purple suit.
Contradiction: some men are inside
Contradiction: A woman behind either a car or bus
Contradiction: We had a six year itch but we did well.