They both involve an exaggerated sense of responsibility for the welfare of others. Survivor guilt arises from perceiving oneself to be better off than a loved one, and relates to the irrational idea that there is a fixed amount of happiness to go around. Thereby one can imagine that one's success comes at the expense of someone else, and feel it is unfair or undeserved. Survivor guilt can also be literal, and arise after the death of a loved one. Separation guilt has by some been described as developmental guilt, as it relates to the belief that one will hurt loved ones by growing up, individualizing and becoming different from the family. CMT describes unconscious guilt as closely intertwined with pathogenic beliefs, and guilt is assumed to play an important role in patients' transference reactions. The development of CMT has been driven forward by an interplay between clinical observations, theory development and empirical research. Some of this research has been psychotherapy research, and in other studies predictions from CMT have been tested or explored outside of the therapeutic setting. Most of the psychotherapy research has been carried out on completed therapies which were recorded and transcribed, and where neither the therapist nor the patient was familiar with the theory. The goal has been to investigate how psychotherapy works regardless of the therapist's orientation or approach. The main tool for studying and evaluating these psychotherapies has been the case formulation. CMT researchers have attempted to operationalize the clinical process of understanding a case, in order to assess and increase agreement between different clinical judges adhering to CMT. The first attempt to assess whether it was possible for trained judges to formulate reliable case formulations based on CMT were done by Caston (1986). In several studies applying this procedure on brief therapies, the interjudge reliabilities were found to be high, typically between .7 and .9. Curtis and Silberschatz later modified and revised the procedure, and termed it the Plan Formulation Method (1991). The "Plan Formulation Method", or "PFM", is a comprehensive case formulation method that was developed primarily for clinical research on CMT. Plan formulations developed for psychotherapy research are based on reviews of transcripts from early therapy sessions. A plan formulation starts with a description of the patient, including his or her current life circumstances and presenting complaints. Beyond that, a control mastery plan formulation consists of the following elements:  Research on the PFM has consistently demonstrated that trained independent judges can achieve a high degree of agreement in formulating case formulations based on CMT concepts, including traumas, goals, obstructions, tests and insights.