Trial Outcomes & Findings for PortionSize Study 2 Free-Living Evaluation (NCT NCT05166226)
NCT ID: NCT05166226
Last Updated: 2025-12-15
Results Overview
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.
ACTIVE_NOT_RECRUITING
45 participants
Mean daily energy intake averaged across 3 day free-living period of each PortionSize app and MyFitnessPal app intervention.
2025-12-15
Participant Flow
Participant milestones
| Measure |
PortionSize Followed by MyFitnessPal
This was a within-subjects, randomized, counterbalanced crossover design. Each participant completed two testing periods: Period 1 and Period 2. Participants were randomly assigned to one of two sequences: (1) PortionSize followed by MyFitnessPal, or (2) MyFitnessPal followed by PortionSize. PortionSize followed by MyFitnessPal group used the PortionSize app to estimate dietary intake during the first study period and switched to MyFitnessPal for the second period.
|
MyFitnessPal Followed by PortionSize
This was a within-subjects, randomized, counterbalanced crossover design. Each participant completed two testing periods: Period 1 and Period 2. Participants were randomly assigned to one of two sequences: (1) PortionSize followed by MyFitnessPal, or (2) MyFitnessPal followed by PortionSize. MyFitnessPal followed by PortionSize group used the MyFitnessPal app to estimate dietary intake during the first study period and switched to PortionSize for the second period.
|
|---|---|---|
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Overall Study
STARTED
|
23
|
22
|
|
Overall Study
COMPLETED
|
23
|
21
|
|
Overall Study
NOT COMPLETED
|
0
|
1
|
Reasons for withdrawal
Withdrawal data not reported
Baseline Characteristics
PortionSize Study 2 Free-Living Evaluation
Baseline characteristics by cohort
| Measure |
All Participants
n=44 Participants
All 44 participants that completed the study
|
|---|---|
|
Age, Continuous
|
44.0 years
STANDARD_DEVIATION 10.8 • n=6009 Participants
|
|
Sex: Female, Male
Female
|
24 Participants
n=6009 Participants
|
|
Sex: Female, Male
Male
|
20 Participants
n=6009 Participants
|
|
Race (NIH/OMB)
American Indian or Alaska Native
|
0 Participants
n=6009 Participants
|
|
Race (NIH/OMB)
Asian
|
2 Participants
n=6009 Participants
|
|
Race (NIH/OMB)
Native Hawaiian or Other Pacific Islander
|
0 Participants
n=6009 Participants
|
|
Race (NIH/OMB)
Black or African American
|
7 Participants
n=6009 Participants
|
|
Race (NIH/OMB)
White
|
35 Participants
n=6009 Participants
|
|
Race (NIH/OMB)
More than one race
|
0 Participants
n=6009 Participants
|
|
Race (NIH/OMB)
Unknown or Not Reported
|
0 Participants
n=6009 Participants
|
|
Region of Enrollment
United States
|
44 participants
n=6009 Participants
|
|
BMI
|
28.6 kilograms per square meter (kg/m²)
STANDARD_DEVIATION 6.7 • n=6009 Participants
|
PRIMARY outcome
Timeframe: 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.
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.
Outcome measures
| Measure |
PortionSize
n=44 Participants
This was a within-subjects, randomized, counterbalanced crossover design. Each participant completed two testing periods: Period 1 and Period 2. Participants were randomly assigned to one of two sequences of interventions: (1) PortionSize followed by MyFitnessPal, or (2) MyFitnessPal followed by PortionSize.
|
MyFitnessPal
n=44 Participants
This was a within-subjects, randomized, counterbalanced crossover design. Each participant completed two testing periods: Period 1 and Period 2. Participants were randomly assigned to one of two sequences: (1) PortionSize followed by MyFitnessPal, or (2) MyFitnessPal followed by PortionSize.
|
|---|---|---|
|
Energy (Kilocalorie or kcal) Intake
|
2128.8 kcal/day
Standard Deviation 762.1
|
2120.0 kcal/day
Standard Deviation 650.1
|
Adverse Events
PortionSize
MyFitnessPal
Serious adverse events
Adverse event data not reported
Other adverse events
Adverse event data not reported
Additional Information
Dr. Corby Martin
Pennington Biomedical Research Center
Results disclosure agreements
- Principal investigator is a sponsor employee
- Publication restrictions are in place