Chronic fatigue syndrome: a qualitative investigation of patients' beliefs about the illness.
Clements, A, Sharpe, M, Simkin, S et al.·Journal of psychosomatic research·1997
This study interviewed 66 people with ME/CFS to understand what they believe causes their illness and how they think they can manage it. Most patients believed their illness was primarily physical, though over half also thought stress played a role. Patients felt they could control symptoms by reducing activity, but believed they could not influence the underlying disease itself.