The usual dietary recall as a dietary assessment method: a scoping review

The evaluation of usual food intake is of central importance in nutritional epidemiology studies. Some authors propose the usual dietary recall (UDR) as a viable method for assessing usual food intake; however, its characteristics remain poorly understood. The objective of this study is to review the literature on the application and performance characteristics of the UDR as a dietary assessment method. Electronic search strategies were conducted using the Excerpta Medica Database, Publisher Medline, Cochrane Central Register of Controlled Trials, Latin American and Caribbean Health Sciences Literature, Coordination for the Improvement of Higher Education Personnel (CAPES) Periodicals Portal, and Google Scholar. Studies published in Portuguese, English, and Spanish were included, with no restrictions on publication date. Eligible studies included those utilising the UDR in experimental or observational designs, as well as literature reviews. A total of 116 studies were included in the review. The most common application method (<i>n</i> 34; 29·3 %) involved reporting foods typically consumed over a 24-h period. However, most studies (<i>n</i> 66; 56·9 %) did not specify the method for applying the UDR. Key limitations identified included under or overestimation (<i>n</i> 9; 7·8 %), memory bias (<i>n</i> 7; 6·0 %) and the lack of instrument validation (<i>n</i> 5; 4·3 %). Findings show that the UDR lacks a standardised application method, and its validity remains unconfirmed. Future research should establish a standardised protocol and assess its psychometric properties to reduce errors and biases, ensuring accurate dietary assessments in nutritional epidemiology.