A systematic review of research using the diagnostic criteria for cancer-related fatigue.

BACKGROUND

Prevalence rates for cancer-related fatigue vary widely depending on how fatigue is defined and assessed. In 1998, formal diagnostic criteria were proposed for a syndrome of cancer-related fatigue. These criteria were intended to facilitate the study of cancer-related fatigue and the development of appropriate interventions to ameliorate fatigue. Although the criteria have been widely cited, to date, there has been no systematic review of research using the criteria that might inform their continued use or revision.

METHODS

We conducted a systematic review of the literature reporting results based on use of the diagnostic criteria. Data were analyzed to characterize the reliability and validity of the criteria and to describe the prevalence of cancer-related fatigue.

RESULTS

We identified nine eligible studies. The purpose of the majority of the studies was to estimate the prevalence of cancer-related fatigue; there was considerable variability with respect to design and nature of the samples included. Although few studies examined reliability of the criteria, findings reported support their reliability. The validity of the criteria judged relative to established measures of fatigue and related constructs appears to be strong. Prevalence rates for cancer-related fatigue based on the diagnostic criteria vary widely, reflecting a lack of consistency in how the criteria have been applied.

CONCLUSIONS

As a comprehensive approach to diagnosing cancer-related fatigue, the diagnostic criteria have received relatively scant attention by the clinical research community. Our findings suggest the need for research aimed at revising the criteria, enhancing their usefulness, and promoting their more widespread use.