Cohen, L., Warneke, C., Fouladi, R. T., Rodriguez, M. A., & Chaoul-Reich, A. (2004). Psychological adjustment and sleep quality in a randomized trial of the effects of a Tibetan yoga intervention in patients with lymphoma. Cancer, 100, 2253–2260.
The Tibetan yoga (TY) intervention involved seven weekly sessions with a yoga instructor who used imagery and exercise and included four aspects: controlled breathing and visualization, mindfulness, two types of posture, and daily practice. Outcomes were psychological adjustment, sleep, and fatigue.
Patients were undergoing the active treatment and long-term follow-up phases of care.
The study used a prospective, quasiexperimental design with two groups, including a wait-list control.
Pittsburgh Sleep Quality Index (PSQI)
The TY group reported significantly lower sleep disturbances scores (total PSQI) at follow-up (5.8 for TY versus 8.1 for the wait-list control). At follow-up, the TY group reported better subjective sleep quality, shorter latency, longer duration, and use of fewer sleep medications.