Research Needs in School Age Populations
"Even after 40 years of research, and a plethora of comparative
studies, there are no universal criteria which can be applied when selecting
data-collection methods suitable for studies of children and adolescents."
Livingston and Robson, 2000 (161)
Drawing conclusions about the validity of available dietary assessment
instruments in school age children is hampered by the differences in instruments,
research design, reference methods, and populations in the validation
literature. Research needs have been identified by a number of authors:
- Studies need to examine the validity and reliability of each dietary
assessment method by age, gender, ethnic subgroup, and socioeconomic
status to understand the best application of each tool (1).
- Development and validation of improved methods for assessing dietary
supplement use are needed (9;64).
- Studies that compare multiple reference measures for a particular
reference assessment method would allow comparisons of the validation
standards best suited for particular situations (161).
- Physiologically-based measures, such as DLW (Doubly Labeled
Water) or serum micronutrient concentrations, merit further study
because these reference measures are not affected by respondent error;
(1;161;201)
a more extensive database of assessments of TEE (Total
Energy Expenditure) by the DLW method is needed.
- Identification and characterization of subgroups most likely to misreport
food intakes, together with the reasons for doing so, need further study,
as does the development of improved techniques to identify underreporters
and overreporters at the individual level (161;201).
- The issue of whether underreporting of diet applies to the diet as
a whole or whether there is selective underreporting of nutrient intake,
whether by food types, meals, or snack foods, needs examination (161).
- The reasons for, and effects of, non-participation by children and
adolescents should be examined to identify possible sources of bias
(non-response bias) and to assess implications for design analysis and
interpretation of results (161;217).
- Developing new or refining existing dietary survey methods that are
sensitive to different ages, cognitive abilities and motivation levels
and that improve accuracy and are not time consuming is needed (1;160;161;204;205).
- The effect of body size on reporting of dietary intake requires further
study (1;161).
- Further research is needed to refine the cognitive model for children's
recall of dietary intake proposed by Barnowski and Domel (160)
and to address many unresolved issues, such as the impact of time and
less experimentally controlled conditions on retention and retrieval
processes (161).
- The effects of a longer time lag between meal recall and environmental
factors on the accuracy of recall in children need to be established
(202).
- The accuracy of child versus parent or caretaker respondents needs
further study (165;218).
- New methods for estimating portion sizes that are sensitive to the
cognitive abilities of children are needed (1;161;202).
- More research is needed on the prompts that can aid memory retrieval
at various ages without increasing the risk of eliciting socially-desirable
responses. Environmentally specific probes (e.g., school, fast food
restaurants, extracurricular activities, media and entertainment, food
industry packaging of foods for children) within a food record or food
frequency questionnaire also are needed (160;161;206;218).
- Refinement of statistical techniques to account for systematic bias
in pediatric populations is needed. Statistical models need to be developed
that will estimate the impact of systematic bias on estimates such as
relative risk, variance ratios, or proportions on the populations with
inadequate intakes (161).
- Emerging technologies should be applied to developing new dietary
assessment methods (e.g., Internet-based self-administered methods or
dietary assessment methods that incorporate cellular telephones, personal
digital assistants, or video recording) (219).
|
