Clusters refers to the classification of different personality disorders in separate groups by the DSM 5, depending on the symptoms displayed. Personality disorder subtypes classified in DSM-5, the third cluster, Cluster C or the fearful or anxious cluster is comprised of Obsessive compulsive, dependent, and avoidant. Fearful cluster includes three personality disorders sharing anxious and fearful features (avoidant personality disorder, dependent, personality disorder and obsessive-compulsive personality disorder).
The three different clusters are based on the descriptive similarities. While dealing with personality disorders, it should be kept in mind that individuals frequently exhibit certain traits that are not limited to a single personality disorder. Every time a patient meets the criteria for more than one personality disorder, clinicians should diagnose each.