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Models

There are many models of common factors in successful psychotherapy process and outcome. Already in 1990, Grencavage and Norcross identified 89 common factors in a literature review, which showed the diversity of models of common factors. To be useful for purposes of psychotherapy practice and training, most models reduce the number of common factors to a handful, typically around five. Frank listed six common factors in 1971 and explained their interaction. Goldfried and Padawer listed five common strategies or principles in 1982: corrective experiences and new behaviors, feedback from the therapist to the client promoting new understanding in the client, expectation that psychotherapy will be helpful, establishment of the desired therapeutic relationship, and ongoing reality testing by the client. Grencavage and Norcross grouped common factors into five areas in 1990. Lambert formulated four groups of therapeutic factors in 1992. Joel Weinberger and Cristina Rasco listed five common factors in 2007 and reviewed the empirical support for each factor: the therapeutic relationship, expectations of treatment effectiveness, confronting or facing the problem (exposure), mastery or control experiences, and patients' attributions of successful outcome to internal or external causes.