This simple approach can provide the solution. Suppose a resident becomes aggressive toward another resident who enters her room. To drill down to the potential causes of the resident's behavior, keep asking why until "you come up with a complete scenario," advises Lynda Mathis, RN, a consultant in Conway, Ark. The root-cause analysis might go like this, Mathis says. Question: "Why did the resident become aggressive?" Answer: "A man was in her room." Question: "Why did she become aggressive toward that particular man?" Answer: "She thought the man was an alien invader." Mathis notes that "the care plan will be different depending on whether the resident thought the man was someone from the facility or an alien invader."