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PortionSize Study 1 Laboratory-based Evaluation)

The Reliability and Validity of the PortionSize and MyFitnessPal Apps (Study 1: Laboratory-based Evaluation)

Status
Completed
Phases
Unknown
Study type
Observational
Source
ClinicalTrials.gov
Registry ID
NCT04700904
Enrollment
43
Registered
2021-01-08
Start date
2021-02-10
Completion date
2024-12-31
Last updated
2025-01-27

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Dietary Habits

Brief summary

The objective is to test the accuracy and user satisfaction of the PortionSize™ app and the MyFitnessPal© app during laboratory controlled test meals.

Detailed description

Accurately quantifying food intake is vital to promoting health and reducing chronic disease risk. Food intake encompasses energy intake, nutrient intake (macronutrients, micronutrients, vitamins, minerals), and intake of various food groups (e.g., fruits, vegetables), and thus reflects the nutritional status of individuals. Nutrition affects disease risk, including risk of developing obesity, diabetes, and cancer, all of which negatively affect the United States (U.S). Nonetheless, accurate assessment of food and nutrient intake has remained challenging, despite an improvement in methods. Self report methods, namely food records, are a mainstay of nutritional epidemiology research, with food recall being another popular method. These methods rely on the participant to accurately estimate portion size and, for food recall, remember what was consumed. The accuracy of these methods have been questioned and the problems with human recall have been comprehensively outlined. As a result, there remains a significant need for methods that are sufficiently accurate to provide researchers with good outcome data and to guide health promotion efforts. The PortionSize™ app was designed by our laboratory to overcome the limitations outlined above, and to guide users to follow specific diets. PortionSize relies on users capturing images of their food selection and waste. Food intake data are immediately provided since the user relies on built in tools, including templates, to estimate portion size. However, despite promising early indications, the PortionSize app's validity has yet to be extensively tested. Determining the accuracy of PortionSize is vital before users can utilize the app to obtain immediate feedback about their food intake. We accordingly aim to test the validity of PortionSize in a controlled laboratory setting. We will also test the validity of the MyFitnessPal© app, which is similar to an electronic food record.

Interventions

None listed

Sponsors

Pennington Biomedical Research Center
Lead SponsorOTHER

Study design

Observational model
CASE_CROSSOVER
Time perspective
PROSPECTIVE

Eligibility

Sex/Gender
ALL
Age
18 Years to 70 Years
Healthy volunteers
Yes

Inclusion criteria

* Male or female, age 18-70 years * Body mass index (BMI) 18.5 - 50 * Ownership of an iPhone model 6s or later, which the participant is willing to use for the study * Access to Apple ID, password, and email address and willing to use them in the course of the study * Willing to use data and any accompanying charges as part of study participation * Willing to be re-contacted for future research and/or follow-up

Exclusion criteria

* Center employee * Any condition or circumstance that could impede study completion

Design outcomes

Primary

MeasureTime frameDescription
Difference in Simulated Energy (kcal) Intake Between the Criterion Measure (Weighed Food) and Two Smartphone Apps (PortionSize and MyFitness Pal).2.5 hoursThe outcome variable was the difference between the criterion measure (directly weighed foods from a simulated lunch meal) and two apps: PortionSize and MyFitnessPal. The outcome measure for the PortionSize app was calculated as: energy intake values from PortionSize minus energy intake values from weighed foods. The outcome measure for the MyFitnessPal app was calculated as: energy intake values from MyFitnessPal minus energy intake values from weighed foods.

Countries

United States

Participant flow

Participants by arm

ArmCount
All Participants
all 42 participants that completed the study
42
Total42

Baseline characteristics

CharacteristicAll Participants
Age, Continuous36.3 years
STANDARD_DEVIATION 16.6
BMI28.2 kg/m^2
STANDARD_DEVIATION 6.9
Race (NIH/OMB)
American Indian or Alaska Native
0 Participants
Race (NIH/OMB)
Asian
2 Participants
Race (NIH/OMB)
Black or African American
10 Participants
Race (NIH/OMB)
More than one race
0 Participants
Race (NIH/OMB)
Native Hawaiian or Other Pacific Islander
0 Participants
Race (NIH/OMB)
Unknown or Not Reported
2 Participants
Race (NIH/OMB)
White
28 Participants
Sex: Female, Male
Female
23 Participants
Sex: Female, Male
Male
19 Participants
Weight81.5 kg
STANDARD_DEVIATION 22

Adverse events

Event typeEG000
affected / at risk
deaths
Total, all-cause mortality
0 / 44
other
Total, other adverse events
0 / 44
serious
Total, serious adverse events
0 / 44

Outcome results

Primary

Difference in Simulated Energy (kcal) Intake Between the Criterion Measure (Weighed Food) and Two Smartphone Apps (PortionSize and MyFitness Pal).

The outcome variable was the difference between the criterion measure (directly weighed foods from a simulated lunch meal) and two apps: PortionSize and MyFitnessPal. The outcome measure for the PortionSize app was calculated as: energy intake values from PortionSize minus energy intake values from weighed foods. The outcome measure for the MyFitnessPal app was calculated as: energy intake values from MyFitnessPal minus energy intake values from weighed foods.

Time frame: 2.5 hours

Population: All participants completed the study protocols using the PortionSize app and the MyFitnessPal app across two study visits (1 app at each visit). Groups defined in the participant progression section distinguish participants who used the PortionSize app first from those who used the MyFitnessPal app first.

ArmMeasureValue (MEAN)Dispersion
PortionSize AppDifference in Simulated Energy (kcal) Intake Between the Criterion Measure (Weighed Food) and Two Smartphone Apps (PortionSize and MyFitness Pal).-150.1 kcalStandard Deviation 489.5
MyFitnessPal AppDifference in Simulated Energy (kcal) Intake Between the Criterion Measure (Weighed Food) and Two Smartphone Apps (PortionSize and MyFitness Pal).79.8 kcalStandard Deviation 583.3

Source: ClinicalTrials.gov · Data processed: Feb 7, 2026