Dick, B. (1975) ‘A Ten Year Study of Out-patient Analytic Group Therapy’, British Journal of Psychiatry 127: 350-375.
Sigrell, B. (1995). ‘The Long-Term Effects of Group Psychotherapy: A Thirteen Year Follow-Up Study’, Group Analysis 25(3): 333-352.
Sheehan, J.D. & Fitzgerald, M. (1994) ‘Measuring Progress in Psychoanalytical Psychotherapy: A Pilot Study’, Group Analysis 27(2): 211-220.
Hall, Z. & King, E. (1997) ‘Group Therapy within the NHS V: Patients’ Views on the Benefit of Group Therapy for Women Survivors of Child Sexual Abuse’, Group Analysis 30(3): 409-427.
Wilberg, T., Friis, S., Karterud, S., Mehlum, L., Urnes, Ø. & Vaglum, P. (1998) ‘Outpatient Group Psychotherapy: A Valuable Continuation Treatment for Patients with Borderline Personality Disorder Treated in a Day Hospital?: A 3 year Follow-up Study’, Nordic Journal of Psychiatry 52: 213-221.
Wilberg, T., Karterud, S., Pedersen, G., Urnes, Ø., Irion, T., Brabrand, l, Haavaldsen, G., Leirvåg, H., Johnsen, R, Andreasen, H. & Stubhaug, B. (2003) ‘Outpatient Group Psychotherapy FolIowing Day Treatment of Patients with Personality Disorders’, Journal of Personality Disorders 17: 510-521.
Heinzel, R., Breyer, F. & Klein, T. (2000) ‘Outpatient Psychoanalytic Individual and Group Psychotherapy in a Nationwide Catamnestic Study in Germany’, Group Analysis 33(3): 353-372.
Tschuschke, V. & Anbeh, T. (2000) ‘Early Effects of Long-term Outpatient Group Therapies – First Preliminary Results’, Group Analysis 33(3): 397–411.
Sharpe, J., Selley, c., Low, L. & Hall, Z. (2001) ‘Group-Analytic Therapy for Male Survivors of Childhood Sexual Abuse’, Group Analysis 34(2): 195-209.
Bateman, A & Fonagy, P. (1999) ‘Effectiveness of Partial Hospitalization in the Treatment of Borderline Personality Disorder: A Randomized Controlled TriaJ’, Arnerican Journal of Psychiatry 156: 1563-1569.
Bateman, A & Fonagy, P. (2001) ‘Treatment of Borderline Personality Disorder with Psychoanalytically Oriented Partial Hospitalization: An 18-Month Followup’, American Journal ()f Psychiatry 158: 36-42.
Valbak, K. (2001) ‘Good Outcome for Bulimic Patients in Long-term Group Analysis: A Single Group Study’, European Eating Disorders Review 9(1): 19-32.
Lorentzen, S. & Høglend, P. (2002) ‘The Change Process of a Patient in Long Term Group Psychotherapy’, Group Analysis 35(4): 500-524.
Lorentzen, S., Bøgwald, K-P. & Høglend, P. (2002) ‘Change During and Af ter Long-term Analytic Group Psychotherapy’, International Journal of Group Psychotherapy 52(3): 419–429.
Lorentzen, S. (2003) Long-term Analytic Group Psychotherapy with Out-patients.
Evaluation of Process and Change. Academic dissertation. University of Oslo.
Conway, S., Audin, K., Barkham, M., Mellor-Clark, J., & RusseII, S. (2003) ‘Practice-based Evidence for a Brief Time-intensive Multi-modal Therapy Guided by Group-analytic Principles and Method’, Group Analysis 36(4): 411-435.
Terlidou, C., Moschonas, D., Kakitsis, P., Manthouli, M., Moschona, T., and Tsegos, I. (2004) ‘Personality Changes of the Completion of Long-term Group Analytic Psychotherapy’, Group Analysis 37(3): 401–418.
Wennberg, P., Weinryb, RM., Saxon L., Goransson, S., Bush, M. & Skaarbrandt, E. (2004) ‘Personality, Levels of Psychological Distress and Premature Termination of Psychodynamic Group Therapy: Results from a Prospective Longitudinal Study’, Group Analysis 37: 179-185.