Skin Carotenoid Score Level and Race Affect Intradevice Repeatability of Veggie Meter® at a Single Time Point

Saima Hasnin; Stephanie B Jilcott Pitts; Charlotte K Roman; Naiman A Khan

doi:10.1016/j.jneb.2025.11.003

Skin Carotenoid Score Level and Race Affect Intradevice Repeatability of Veggie Meter® at a Single Time Point

J Nutr Educ Behav. 2026 Feb;58(2):135-143. doi: 10.1016/j.jneb.2025.11.003. Epub 2025 Dec 9.

Authors

Saima Hasnin¹, Stephanie B Jilcott Pitts², Charlotte K Roman³, Naiman A Khan⁴

Affiliations

¹ Department of Food Science and Human Nutrition, University of Illinois Urbana-Champaign, Urbana, IL; Division of Nutritional Sciences, University of Illinois Urbana-Champaign, Urbana, IL. Electronic address: shasnin@illinois.edu.
² Department of Public Health, East Carolina University, Greenville, NC.
³ Department of Health and Kinesiology, University of Illinois Urbana-Champaign, Urbana, IL.
⁴ Division of Nutritional Sciences, University of Illinois Urbana-Champaign, Urbana, IL; Department of Health and Kinesiology, University of Illinois Urbana-Champaign, Urbana, IL; Beckman Institute for Advanced Science and Technology, Urbana, IL; Neuroscience Program, College of Liberal Arts and Sciences, University of Illinois Urbana-Champaign, Urbana, IL.

PMID: 41364045
DOI: 10.1016/j.jneb.2025.11.003

Abstract

Objective: To compare the reliability of 2 methods (3 scan average vs average of scan 2 and 3) of skin carotenoid score (SCS) measurement and identify participant-level factors affecting intradevice repeatability of Veggie Meter® (VM).

Design: Cross-sectional study in Illinois.

Participants: The sample (N = 587) included about 36% children, 27% adolescents, and 32% adults; 67% were White, 14% Asian, 10% Black or African American, 8% mixed race, 1% Native Hawaiian, and 0.4% American Indian; 92% were non-Hispanic, and 53% female.

Variable measured: Three consecutive SCS readings using 2 devices. Self-reported or parent-reported demographic information.

Analysis: Paired sample t-tests compared the coefficient of variation of the 3-scan average SCS with the coefficient of variation of the second and third-scan average SCS. We conducted sign tests and generated Bland-Altman plots to determine the type of errors. Kruskal-Wallis and Mann-Whitney tests assessed if repeatability coefficients of the 3 consecutive SCS readings were different across age, race, ethnicity, and SCS quartiles, where repeatability coefficients = within-subject SD × √2 × 1.96.

Results: Averaging the second and third scans of SCS produced 1.2% higher reliability in VM 1 and 0.7% higher reliability in VM 2 than averaging all 3 scans (t_{VM 1} = -7.1, P < 0.001; t_{VM 2} = -3.1, P = 0.002). Repeatability coefficients were significantly higher among participants with higher SCS than lower SCS, in both devices (H_{VM 1} = 30.2, P < 0.001; H_{VM 2} = 9.7, P = 0.02). Pairwise comparisons showed that repeatability coefficients were significantly lower for Black or African American participants than White (mean SCS difference = 22.3, P = 0.001) and Asian participants (mean SCS difference = 23.7, P = 0.005) in one device (VM 1).

Conclusion and implications: Findings support using the average of the second and third scans as a more reliable method for assessing SCS. Reporting device-specific repeatability coefficients for the VM may enhance the interpretability of SCS, particularly for individuals with low SCS and for Black or African American participants.

Keywords: Veggie Meter®; reliability; repeatability; skin carotenoid score.

MeSH terms

Adolescent
Adult
Carotenoids* / analysis
Child
Cross-Sectional Studies
Female
Humans
Male
Middle Aged
Racial Groups* / statistics & numerical data
Reproducibility of Results
Skin* / chemistry
Young Adult

Substances

Carotenoids