A client who was just told he has cancer says, 'There must be a mistake with the test. I feel fine.' Which defense mechanism is this?

DENIAL is the refusal to acknowledge a painful or threatening reality. In this case, the client is refusing to accept the diagnosis ('There must be a mistake') and providing a rationalization for it ('I feel fine'). Denial is often the FIRST stage of grief (Kübler-Ross) and is a common initial response to a devastating diagnosis. SHORT-TERM DENIAL can be protective — it gives the psyche time to adjust. However, PROLONGED DENIAL can prevent a person from seeking needed treatment or making important decisions. NURSING APPROACH: do not immediately challenge denial; give the client time; gently present reality as the relationship develops; avoid reinforcing denial ('Maybe they are wrong'); work with the healthcare team on timing and approach. COMMON DEFENSE MECHANISMS: DENIAL — refusing to accept reality; RATIONALIZATION — making excuses to justify behavior or feelings ('I drink because my job is stressful'); PROJECTION — attributing one's own unacceptable feelings to others ('He's the one who's angry, not me'); SUBLIMATION — channeling unacceptable urges into socially acceptable activities (channeling aggression into competitive sport); DISPLACEMENT — redirecting emotions to a safer target (yelling at the dog after a fight with your boss); REPRESSION — unconsciously blocking painful memories from conscious awareness; REGRESSION — returning to earlier developmental behavior when stressed (a toilet-trained child begins bedwetting during family stress); REACTION FORMATION — acting opposite to how one actually feels (being excessively nice to someone you dislike); INTELLECTUALIZATION — using facts and analysis to avoid emotional processing; SUPPRESSION — CONSCIOUSLY pushing thoughts away (different from repression which is unconscious).