Forty patients suffering from persistent psychophysiological Disorders of Initiating and Maintaining Sleep (DIMS) were assigned to one of the following groups: (1) EMG-biofeedback training; (2) cognitive modification treatment, combining paradoxical instructions, cognitive restructuring and thought stopping; (3) stimulus control and progressive relaxation treatment; (4) waiting list (control). Each active treatment consisted of six sessions over a period of 2 weeks.
After treatment, the patients in the three treatment groups showed shorter sleep onset latency (37%), shorter wake time after sleep onset (50%), and more positive evaluations of sleep quality and restedness on awakening in the morning. The waiting-list group did not show any changes. Benefits were maintained and further increased during the 1 and 3 year follow-ups. Results did not suggest substantial differences, among the three treatments, in amount and/or stability of benefits. The 3 year follow-up revealed seven failures, as against 23 successes. The initial variables differentiating the failures were shorter sleep time and higher scores on the P scale of the Eysenck Personality Questionnaire.