Common factors are factors that are common to changes that take place in Psychotherapy and Counseling that include participant and relationship factors; set of features that characterize many Therapy orientations and that may be the source of the positive changes effected by psychological treatment. Common factors are general factors found in most forms of Therapy, example, the Therapist's personal qualities that help the client to recover.
Lexicon of Psychology - Terms, Treatments, Biographies,