Overcoming difficulties in demonstrating health outcome benefits

Nutrition interventions with cancer patients may produce benefits beyond those typically evaluated, such as increased appetite, food intake, and weight gain. Other benefits include enhanced mood, improved sense of well-being, and increased socialization because of an increased ability to eat in public or with family. Along with the target benefits of nutrition interventions, these "untargeted" benefits have come to be clustered under the general rubric of health-related quality of life. All medical treatments, including nutrition interventions, can be evaluated in terms of their total effect upon health-related quality of life. However, demonstrating health outcome benefits of nutrition interventions can be very difficult. This difficulty is at two levels: conceptual and practical. Conceptual difficulties can be overcome by refining and clarifying the definition and measurement of health-related quality of life. Practical difficulties are more diverse and must be tackled on a point-by-point basis, depending upon the unique characteristics of the disease being treated, the intervention being tested, and the context of the trial. This paper offers some guidelines and recommendations for overcoming many of the more commonly confronted barriers to successful demonstration of health outcome benefits from clinical nutrition trials with cancer patients.