Evaluation of the Symptom Representation Questionnaire (SRQ) for assessing cancer-related symptoms

Multidimensional, multisymptom approaches to cancer symptom assessment and management have been emphasized across health disciplines. However, each dimension that is assessed significantly increases patient/subject burden. Efficient, reliable, and valid assessment of the critical dimensions of patients' most salient symptoms is important in clinical and research settings. The Symptom Representation Questionnaire (SRQ), derived from information processing theory, assesses critical cognitive and emotional factors that are known to influence coping and outcomes. The SRQ was developed and evaluated in a three-phase process: (1) item selection, modification, and review by theoretical and clinical experts; (2) pilot evaluation of feasibility and psychometric properties; and (3) large sample psychometric evaluation. In Phase 3, members (n=713) of the National Ovarian Cancer Coalition participated via mailed surveys. Internal consistency was good for all subscales (alpha=0.63-0.88). The internal structure of the SRQ was theoretically consistent except that emotional representation, identity, and consequence items all loaded onto a single factor. Between-group comparisons supported construct validity: Representations differed between long-term survivors and women with active disease. Finally, there were significant correlations between SRQ subscales and Symptom Interference and Life Satisfaction. The SRQ appears to be a psychometrically sound instrument for assessing representations of cancer-related symptoms. This instrument could play an essential role in advancing knowledge of the relationships among representations of symptoms, symptom management processes, and symptom-related outcomes. It could also be used in intervention research when changes in symptom representations are hypothesized to mediate changes in outcomes as a result of psychoeducational interventions.