Systematic Review of the Effect of a One-Day Versus Seven-Day Recall Duration on Patient Reported Outcome Measures (PROMs).

This review identified a clear trend toward higher symptom scores and worse quality of life being reported for a seven-day compared to a one-day recall. The review also identified anomalies in this pattern for some wellbeing items and a need for further research on positively framed items. A better understanding of the impact of using different recall periods within PROMs and HRQoL instruments will help contextualise future comparisons between instruments. Questionnaires ask patients about their health over different time periods (e.g., "what were your symptoms like over the last week?" versus "what were your symptoms like today?"). Studies find that people may report their symptoms as more severe when they are asked to think about their symptoms over the last week compared to the last day. Understanding how different time periods influence patient responses will allow researchers to compare and develop new questionnaires and may help clinicians to choose the best questionnaire to understand their patient's condition. We conducted a systematic literature review on studies which had looked at the impact of using different recall periods on patient responses. We found 24 studies that compared patient scores from questionnaires asking their health "over the last day" compared to "over the last week". Overall, symptoms tended to be reported as more severe and health as poorer when they were reported over the last week compared to the last day on average. We also found 33 studies that asked patients to describe which recall period they preferred. Patients had mixed preferences with more preferring a seven-day recall where symptoms and health impacts varied a lot.