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Updated: Nov 26, 2025
'Boden Food Plate': Novel Interactive Web-based Method for the Assessment of Dietary Intake
Published on: September 18, 2018
The Failure of Plate Diagrams in Estimating Individualized Offered Portion Size: An enable Study
Angela Ott1, Maria Voigt1, Cornel Christian Sieber2
1Institute for Biomedicine of Aging, Friedrich-Alexander-Universität Erlangen-Nürnberg, Nürnberg, Germany.
Background/Objectives:
Plate diagrams (PDs) are commonly used to monitor dietary intake in nursing homes (NHs). PD intake estimation of texture-modified diet (TMD) is reliable, but only if the offered portion is determined by weighing records (WRs). Offered portion size is usually individualized in NHs and WRs are impractical for NH routine. Thus, an estimation of offered portion size by PDs seems to be appropriate but its validity is unknown. Further, validity of PDs for intake estimation based on estimated offer (instead of WRs) is unknown.
Design:
Main meal dietary offer and intake were assessed via PDs and WRs.
Setting And Participants:
Seventeen NH residents receiving TMD regularly.
Methods:
Offered portion size and intake of breakfast, lunch, and dinner at 42 days were estimated by nursing personnel via PDs (answer options offered portion size: >standard, standard, ¾, ½, ¼, nothing, I do not know; answer options intake: all plus second helping, all, ¾, ½, ¼, nothing, I do not know). In parallel, scientific personnel weighed all offered food items and leftovers. PD estimation of offered portion size was multiplied by energy and protein content of predefined standard portions. Afterward, PD estimation of intake was multiplied by PD determined energy and protein offer to determine the estimated energy and protein intake. PD determined offer and intake were compared with weighed offer and intake.
Results:
Seventeen residents (14 female) with a mean [±standard deviation (SD)] age of 87.1 (±7.5) years participated in the study. Nursing personnel overestimated offer and intake. Mean daily differences (±SD) between WR and PD determined offer were -349.0 (±315.7) kcal, P < .001, (-36.3% of mean weighed energy offer) and -15.0 (±12.8) g protein, P < .001, (-42.2% of mean weighed protein offer). Mean daily differences (±SD) between WR and PD determined intake were -283.0 (±299.8) kcal, P < .001, (-35.1% of mean weighed energy intake) and -12.6 (±12.7)g protein, P < .001, (-43.1% of mean weighed protein intake).
Conclusions And Implications:
PD estimation of individualized offered portion size of TMD by nursing staff is not valid and can, thus, not be recommended. The mistake in estimation of offered portion size is continued on intake estimation but does not become larger, which supports the use of PDs for intake estimation but just in case of a WR determined offer.
