The strengths and weaknesses of dietary survey methods in materially deprived households in England: a discussion paper.

In 1998, a review for the Ministry of Agriculture Fisheries and Food (the predecessor of the Food Standards Agency) was published evaluating the relative merits of different dietary assessment methods against a series of factors likely to affect compliance or accuracy in low-income households. The review informed the design of a method comparison study carried out in London, UK, in 2001, in which the validity and acceptability of 4 d dietary assessment methods based on 24 h recalls, food checklists and a semi-weighed method were compared with 4 d weighed inventories and other reference measures. Results were based on observations in 384 respondents (159 males, 225 females) aged 2-90 years in 240 households. Outcomes of the comparison study included evaluations of each method made by respondents, interviewers and researchers. These findings were used in the present paper to update and extend the 1998 review. Additional factors not included in the 1998 review have been considered. This updated and extended review provides the basis for discussion of the relative merits of approaches to dietary assessment in low-income households in developed economies. The evidence presented here and elsewhere suggests that the 24 h recall is the method best suited for dietary assessment in low-income households, followed by the weighed inventory, food checklist and lastly the semi-weighed method.