Does recall period have an effect on cancer patients' ratings of the severity of multiple symptoms?

Context: Choosing an appropriate recall period for symptom assessment in a clinical trial is dependent on the design and purpose of the trial.

Objective: To examine the effects of recall on symptom severity ratings by comparing ratings made using 24-hour and seven-day recall periods of the MD Anderson Symptom Inventory (MDASI).

Methods: Forty-two patients in their third to eighth week of chemoradiation rated their symptoms using the MDASI on two separate occasions (T1 and T2), one week apart. At T1, patients were randomly assigned to rate symptoms using either a 24-hour or a seven-day recall. At T2, patients rated symptoms using the recall period not used at their first visit.

Results: Comparing the 24-hour and seven-day recall periods, the correlation coefficient for total symptom severity was 0.888. All correlation coefficients for symptom severity items were >0.7 except for distress (r=0.67). The percentages of moderate to severe symptoms (rated >or=5) were consistent for both recall periods, with no significant difference between recall periods in the prevalence of moderate to severe symptoms. Cronbach alpha coefficients for both 24-hour and seven-day recalls were >0.8. Symptoms from both recall periods were more severe for patients with poorer performance status. Twenty patients were cognitively debriefed; 70% thought that the seven-day recall was "more appropriate" for the MDASI, but 85% did not think that recall period would influence their answers.

Conclusion: This study demonstrated that the MDASI in a seven-day recall format has psychometric properties consistent with the 24-hour recall version, which may promote its use in future cancer clinical trials and may inform the choice of recall period when symptoms are outcome measures.