Am J Psychiatry 1989; 146:254-256
Copyright © 1989 by American Psychiatric Association
Continuing in treatment as a form of selection bias
MJ Edlund and AC Swann
General Adult Clinic, University of Texas Mental Sciences Institute, Houston.
Panic patients who continued treatment (N = 12) did not have symptom scores
significantly different from those of patients who declined or discontinued
treatment (N = 12) but they did have lower pretreatment MHPG levels.
Continuing in treatment may itself cause selection bias for biochemical
variables under study.
