Research
Adherence
Using multiple 24-hour recalls (averaging 2-3) significantly improves the correlation with true intake compared to a single recall, but still yields low attenuation factors for energy and protein.
If you must use self-report, do not rely on a single day. Use 2-3 days of recalls to improve accuracy, but understand that the correlation with true intake remains low (0.31 for energy). For precise absolute intake, use biomarkers.
StrongQualifiesHIGH confidence
Using a single 24-hour recall, the coefficients were 0.26, 0.40, and 0.36, respectively, for the same nutrients and rose to 0.31, 0.49, and 0.46 when three 24-hour recalls were averaged.
Why this rating
Pooled analysis of 5 large validation studies.
Source
Pooled Results From 5 Validation Studies of Dietary Self-Report Instruments Using Recovery Biomarkers for Energy and Protein Intake
Laurence S. Freedman et al. · American Journal of Epidemiology · 2014
Meta-analysis · 5 studiesCited 524×
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