Generalizability and durability of treatment effects in an intervention program for coronary-prone (Type A) managers

To test the reliability and durability of positive treatment effects obtained in a type A intervention project for healthy managers, the analysis was extended to data available from a third treatment group (a special behavior therapy group for participants eliminated from the main sample because of manifestations of clinical CHD) and to measures obtained 6 months following the end of treatment. Immediately after treatment all three groups showed a similar pattern of improvement, although the two behavior therapy groups did show a greater decrease in serum cholesterol levels. Six months after treatment the sample as a whole showed good maintenance of treatment effects, but the differences between groups had become somewhat sharper, with the special behavior therapy group faring best, the regular behavior therapy group intermediate, and the psychotherapy group worst. The logical consistency of these findings increases our confidence in the initial treatment results, as well as permitting cautious optimism concerning the possibility of developing effective intervention programs for coronary-type (type A) behavior.