British Journal of Nutrition

Research Article

Attainment of precision in implementation of 24h dietary recalls: INTERMAP UK

Claire Robertsona1 c1, Rana Conwaya2, Barbara Dennisa3, John Yarnella4, Jeremiah Stamlera5 and Paul Elliotta1

a1 Department of Epidemiology and Public Health, Imperial College London, St Mary's Campus, Norfolk Place, London W2 1PG, UK

a2 Department of Nutrition and Dietetics, King's College London, 150 Stamford Street, London SE1 8WA, UK

a3 Department of Biostatistics, Collaborative Studies Coordinating Center, University of North Carolina at Chapel Hill, Chapel Hill NC, USA

a4 Department of Epidemiology and Public Health, The Queen's University of Belfast, Mulhouse Building, Grosvenor Road, Belfast BT12 6BA, UK

a5 Department of Preventive Medicine, Feinberg School of Medicine, Northwestern University, Chicago IL, USA


Collection of complete and accurate dietary intake data is necessary to investigate the association of nutrient intakes with disease outcomes. A standardised multiple-pass 24 h dietary recall method was used in the International Collaborative Study of Macro- and Micronutrients and Blood Pressure (INTERMAP) to obtain maximally objective data. Dietary interviewers were intensively trained and recalls taped, with consent, for randomly selected evaluations by the local site nutritionist (SN) and/or country nutritionists (CN) using a twelve-criterion checklist marked on a four-point scale (1, retrain, to 4, excellent). In the Belfast centre, seven dietary interviewers collected 932 24 h recalls from 40–59-year-old men and women. Total scores from the 134 evaluated recalls ranged from thirty-four to the maximum forty-eight points. All twelve aspects of the interviews were completed satisfactorily on average whether scored by the SN (n 53, range: probing 3·25 to privacy of interview 3·98) or CN (n 19, range: probing 3·26 to pace of interview and general manner of interviewer 3·95); the CN gave significantly lower scores than the SN for recalls evaluated by both nutritionists (n 31, Wilcoxon signed rank test, P=0·001). Five evaluations of three recalls identified areas requiring retraining or work to improve performance. Reporting accuracy was estimated using BMR; energy intake estimates less than 1·2 × BMR identifying under-reporting. Mean ratios in all age, sex and body-mass groups were above this cut-off point; overall, 26·1 % were below. Experiences from the INTERMAP Belfast centre indicate that difficulties in collection of dietary information can be anticipated and contained by the systematic use of methods to prevent, detect and correct errors.

(Received February 02 2005)

(Revised June 08 2005)

(Accepted June 09 2005)


c1 *Corresponding author: Dr Claire Robertson, fax +44 20 7402 2150, email