The 81 patients were randomly assigned to one of 6 groups (two kinds of biofeedback, no biofeedback, with or without relaxation -- that is, electromyographic biofeedback, skin temperature biofeedback, and no biofeedback groups, combined with either relaxation therapy and no relaxation therapy).
Outcomes were assessed with physiological, patient-reported and nurse-reported measures, taken over 5 consecutive chemo treatments.
The investigators found that relaxation therapy patients showed decreases in nausea and anxiety during chemo, and decreases in physiological arousal measures after. On the other hand, the 2 biofeedback interventions yielded some reduction in physiological indices, but no other effects.
The study concludes that relaxation therapy is effective in reducing adverse consequences of chemotherapy; and that past data on the effectiveness of biofeedback was probably due to its having been combined with relaxation therapy, and not to the biofeedback alone.
Citation: Preparing patients for cancer chemotherapy: effect of coping preparation and relaxation interventions. Burish TG, Snyder SL, Jenkins RA. Journal of Consulting & Clinical Psychology: 1991 Aug;59(4):518-25.