Dietary intake assessment - 24-hr recall

24hrs recall image

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Population of Interest (P=Parent, R=Researcher, C=Child)

  • Age: <1 yr (P); 1-10 yrs (P); 3-5 yrs (P); 10-12 yrs (P and/or C); 12 yrs+ (C)
  • Setting: Clinical; Home; Community; Population
  • Administration Method: Face to Face; CATI

24-hr recall

This method involves a structured interview. A trained interviewer asks child and/or adult to recall all food and drink during previous 24 hours. A 24-hour recall can be administered via paper records or with a computer-assisted program. Prompts for quantification of portion size or use of food models are typically employed.


Improves with child’s age and adult assistance. Overcomes the age related bias as seen with diet records. Parents can proxy for children <8yr and can assist older children. Food record prompts can be used. Dietary energy intake is often over or under-estimated. Energy intake over-estimated in children <9, but accurate for 15-18 year old children.

When to use

For estimating group means, that is to get an average of intakes for a group of children; a single recall is sufficient. All days of the week should be equally represented, or at least weekdays and weekend days, due to differences in dietary intakes between days of the week.

For estimating the distribution of individual intakes within a group or for obtaining usual individual intake; multiple recalls need to be collected. The number of days needed depends on the day-to-day variation of intake of the nutrient of interest and the level of precision desired for the research study. For energy and the macronutrients (protein, carbohydrates and fat), 3-10 days has been suggested. For other nutrients such as micronutrients (calcium, iron, folate) up to 50 days may be required.

Four to 5 days are often selected as a reasonable compromise for assessing energy & the macronutrients. If an estimate of long-term intake is required, 3-4 days in each of the four seasons of the year is ideal (ie. 12-16 days in total).


In adults, recalls tend to underestimate intake by about 10% compared with observed intake.

Participant burden

Low for single recall as only small amount of time required. However there is increased burden for increasing number of recalls.

Considerations (miscellaneous)

It should also be noted that in order to effectively implement a 24-hour recall in research settings, quality control procedures both in the training of individuals who will be collecting the data both before collection begins and also during data collection.

After the age of 8, it has been reported that children can just as accurately report dietary intake as their parents, but only for the previous 24 hours. As the length of time between acquisition of data increases, the reporting accuracy decreases, thus in relation to research of dietary intake in children the sooner the food is recalled about a certain time period, the greater the accuracy of the information obtained.


  • Inexpensive
  • quick
  • lower respondent burden
  • can assess current or past diet, can be repeated to gain measure of daily variation and improve precision. Respondents are less likely to change eating pattern because of short collection time
  • no literacy requirement,
  • applicable for broad populations of different ethnicity,
  • can be conducted successfully both face-to-face or over the phone.


Biases caused by errors in memory, perception, conceptualization of food portion sizes, presence of observer. Usual intake of an individual cannot be assessed from one day’s intake due to day by day variability. Repeated 24-hr recalls needed to get population distributions of habitual intake. The method is dependent on regular eating habits. Food composition tables are used to estimate nutrient intake.

Recall methods require the use or access to a nutrient analysis program in order to examine and evaluate data collected. This then poses the problem of how up-to-date the nutrition composition tables and how appropriate the tables are to the actual food compositions of foods available in the area where the data was collected.