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PortionSize Study 2 Free-Living Evaluation

The Reliability and Validity of the PortionSize™ and MyFitnessPal Apps (Study 2: Semi-controlled, Free-living Evaluation)

Status
Completed
Phases
Unknown
Study type
Observational
Source
ClinicalTrials.gov
Registry ID
NCT05166226
Enrollment
45
Registered
2021-12-21
Start date
2022-01-10
Completion date
2026-03-31
Last updated
2026-05-13

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 of the PortionSize™ app and the MyFitnessPal© app at measuring energy and nutrient intake in free-living conditions. Participants will use PortionSize™ and MyFitnessPal apps in separate periods to test the accuracy of the respective apps.

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 has yet to be fully validated. Determining the accuracy and reliability of PortionSize™ is vital before the app can be used by people to obtain immediate feedback about their food intake. We accordingly aim to test the reliability and validity of PortionSize™ in a semi-controlled free-living environment using food provision, where participants consume pre-weighed food from a cooler and return the plate waste in the cooler. We will also test the reliability and validity of the MyFitnessPal app in the same semi-controlled free-living environment. The accuracy of the apps will also be compared to each other.

Interventions

None listed

Sponsors

Pennington Biomedical Research Center
Lead SponsorOTHER

Study design

Observational model
CASE_ONLY
Time perspective
PROSPECTIVE

Eligibility

Sex/Gender
ALL
Age
18 Years to 62 Years
Healthy volunteers
Yes

Inclusion criteria

Male or female, age 18-62 years * Body mass index (BMI) 18.5-50 kg/m2 * Subjects who are capable of giving informed consent and complying with all study procedures/requirements. * 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 during the study * Willing to use data and any accompanying charges as part of study participation * Willing to complete all study procedures and adhere to study visit timelines * Willing to be re-contacted for future research and/or follow-up

Exclusion criteria

* Active cancer diagnosis (excluding some melanomas) * Have been 6-month weight unstable (gain/loss \>10 lbs in last 6 months) * Undergoing weight loss treatment * PBRC employee, as previous reviewers argued that they are not representative of the community * Women who are currently pregnant or breastfeeding (self-reported) * Diagnosed with an uncontrolled thyroid disorder (controlled = 3 months of medication) * Have had or plan to have weight loss surgery (gastric band removal may be allowed at PI discretion) * Allergic to or unwilling to eat study foods provided (exceptions made at the discretion of the PI) * Consume \>28 alcoholic beverages per week * Anyone severely immunocompromised * Any condition or circumstance that in the judgement of the PI could interfere with study participation

Design outcomes

Primary

MeasureTime frameDescription
Energy (Kilocalorie or kcal) IntakeMean daily energy intake averaged across 3 day free-living period of each PortionSize app and MyFitnessPal app intervention.The primary analyses assessing equivalence between PortionSize™ and the criterion measure (and MyFitnessPal and the criterion measures) will rely on equivalence testing using the Two One-side T-test (TOST) method. The null hypothesis of an equivalence tests is that the means are nonequivalent, i.e., the confidence interval of the mean of the test condition exceeds the pre-specified error bound. The alternative hypothesis is that the means are equivalent, and the mean difference between the experimental method and gold standard is hypothesized to be zero. Differences in error from PortionSize™ compared to error from MyFitnessPal will be assessed using dependent samples t-tests, with error calculated as the difference between each experimental method and the criterion variable (e.g., energy intake values from PortionSize™ minus energy intake values from weighed foods). These procedures will also produce results indicating if the error from each method differs from zero.

Countries

United States

Contacts

PRINCIPAL_INVESTIGATORCorby K Martin, PhD

Pennington Biomedical Research Center

PRINCIPAL_INVESTIGATORJohn W Apolzan, PhD

Pennington Biomedical Research Center

Participant flow

Participants by arm

ArmCount
All Participants
All 44 participants that completed the study
44
Total44

Baseline characteristics

CharacteristicAll Participants
Age, Continuous44.0 years
STANDARD_DEVIATION 10.8
BMI28.6 kilograms per square meter (kg/m²)
STANDARD_DEVIATION 6.7
Race (NIH/OMB)
American Indian or Alaska Native
0 Participants
Race (NIH/OMB)
Asian
2 Participants
Race (NIH/OMB)
Black or African American
7 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
0 Participants
Race (NIH/OMB)
White
35 Participants
Region of Enrollment
United States
44 participants
Sex: Female, Male
Female
24 Participants
Sex: Female, Male
Male
20 Participants

Adverse events

Event typeEG000
affected / at risk
EG001
affected / at risk
deaths
Total, all-cause mortality
0 / 440 / 44
other
Total, other adverse events
0 / 440 / 44
serious
Total, serious adverse events
0 / 440 / 44

Outcome results

Primary

Energy (Kilocalorie or kcal) Intake

The primary analyses assessing equivalence between PortionSize™ and the criterion measure (and MyFitnessPal and the criterion measures) will rely on equivalence testing using the Two One-side T-test (TOST) method. The null hypothesis of an equivalence tests is that the means are nonequivalent, i.e., the confidence interval of the mean of the test condition exceeds the pre-specified error bound. The alternative hypothesis is that the means are equivalent, and the mean difference between the experimental method and gold standard is hypothesized to be zero. Differences in error from PortionSize™ compared to error from MyFitnessPal will be assessed using dependent samples t-tests, with error calculated as the difference between each experimental method and the criterion variable (e.g., energy intake values from PortionSize™ minus energy intake values from weighed foods). These procedures will also produce results indicating if the error from each method differs from zero.

Time frame: Mean daily energy intake averaged across 3 day free-living period of each PortionSize app and MyFitnessPal app intervention.

Population: All participants completed two study periods using both the PortionSize and MyFitnessPal apps. Outcome measures are summarized by intervention (PortionSize vs. MyFitnessPal), pooling data across all participants regardless of the order in which apps were used.

ArmMeasureValue (MEAN)Dispersion
PortionSizeEnergy (Kilocalorie or kcal) Intake2128.8 kcal/dayStandard Deviation 762.1
MyFitnessPalEnergy (Kilocalorie or kcal) Intake2120.0 kcal/dayStandard Deviation 650.1

Source: ClinicalTrials.gov · Data processed: May 14, 2026