Introduction: Fatigue is a ubiquitous symptom. Fatigue following cancer diagnosis and treatment continues to be reported with a wide range of prevalence, potentially due to the lack of consensus on the diagnostic criteria for the syndrome and the diversity of tools (predominantly self-reported) used to measure it. While questionnaire scales are useful for screening they provide only sparse information on the nature of the symptom. We report on the development of a semi-structured clinical interview schedule to reliably identify cancer related fatigue syndrome and differentiate co-morbid symptoms such as insomnia or mood disturbance.
Methods: Analogous to clinical interview schedules used in sleep medicine or psychiatry, a semi-structured clinical interview to identify post cancer fatigue (PCF) has been developed. It incorporates published diagnostic criteria for the syndromes of cancer related fatigue; chronic fatigue and major depression. Importantly, clinically significant fatigue can be identified.
Results: An algorithm for classification of the symptom complexes is incorporated together with the assessment of symptom severity. For validation, the interview is currently being trialled in a series of patients with clinician identified fatigue syndromes such as multiple sclerosis, post infectious and chronic fatigue and post cancer fatigue. An interviewer training manual and supplementary instructional DVD are also currently in development.
Conclusion:The interview schedule will facilitate the diagnosis of cancer related fatigue syndrome. It has the potential to facilitate both aetiopathological studies by identifying homogenous cases of the syndrome, and clinical management by monitoring patients participating in clinical intervention trials for cancer related fatigue.