Personality Disorders Personality disorders are defined as a lifelong pattern of behavior that is different from the expectations of an individual’s culture. The DSM-5 identifies specific criteria for diagnosis of a personality disorder. Instructions For this assessment, complete the following: Describe the primary features of cluster B personality disorders. Explain obstacles that can make personality disorders resistant to treatment. Identify the factors that contribute to the development of personality disorders. Explain what type of treatment would be effective for the cluster B personality disorders. Read the scoring guide for this assessment before submitting it.