SUPPLEMENTARY MATERIALS
VALIDATION OF INTERNET-BASED SELF-REPORTED ANTHROPOMETRIC, DEMOGRAPHIC DATA AND PARTICIPANT IDENTITY IN THE FOOD4ME STUDY
Author contribution
The authors’ responsibilities were as follows: JCM developed the concept for the study. CCM and KML drafted the paper and performed the statistical analysis for the manuscript. YM, IT, CAD, ERG, LB, JAL, JAM, WHMS, HD, MG and JCM contributed to the research design. JCM was the Proof of Principle study leader and drafted the paper. CCM, CFMM, HF, CBO, CW, AM, RF, SNC, RSC, SK, LT, CPL, MG, AS, MCW, ERG, LB and JCM contributed to the developing the Standardised Operating Procedures for the study. CCM, SNC, RSC, CW, CBO, HF, CFMM, AM, RF, SK, LT, CPL, MG, AS, MCW and JCM conducted the intervention. CCM, CFMM and WHMS contributed to physical activity measurements. LDP contributed to interpretation of genotypic analysis. UK made the video instructions for data collection. All authors contributed to a critical review of the manuscript during the writing process. All authors approved the final version to be published. None of the authors had conflict of interest.
Table S1. Summary statistics and correlation coefficients for self-reported and measured height, weight and BMI by country.
Variables / Collection method / P-valueaSelf-reported / Measured / ICC (95%CI)b
By country:
Ireland (n=20)
Height (cm) / 173.2 ± 10.5 / 173.1 ± 9.9 / 0.681 / 0.990 (0.976 to 0.996)*
Weight (kg) / 78.1 ± 14.9 / 78.6 ± 15.0 / 0.121 / 0.997 (0.991 to 0.999)*
BMI (kg.m-2) / 26.0 ± 4.3 / 26.2 ± 4.4 / 0.222 / 0.988 (0.971 to 0.995)*
Netherlands (n=20)
Height (cm) / 168.1 ± 9.5 / 168.3 ± 9.1 / 0.521 / 0.993 (0.982 to 0.997)*
Weight (kg) / 69.8 ± 12.0 / 70.5 ± 12.7 / 0.014 / 0.994 (0.986 to 0.998)*
BMI (kg.m-2) / 24.8 ± 4.4 / 25.0 ± 4.6 / 0.129 / 0.993 (0.983 to 0.997)*
Germany (n=19)
Height (cm) / 175.0 ± 7.0 / 171.3 ± 6.5 / 0.019 / 0.985 (0.963 to 0.994)*
Weight (kg) / 74.5 ± 12.4 / 75.4 ± 13.7 / 0.076 / 0.987 (0.966 to 0.995)*
BMI (kg.m-2) / 24.2 ± 3.2 / 24.7 ± 3.6 / 0.030 / 0.966 (0.916 to 0.987)*
Greece (n=21)
Height (cm) / 170.3 ± 8.5 / 170.0 ± 8.2 / 0.223 / 0.988 (0.970 to 0.995)*
Weight (kg) / 75.7 ± 16.1 / 76.6 ± 16.6 / 0.016 / 0.994 (0.986 to 0.998)*
BMI (kg.m-2) / 25.9 ± 4.3 / 26.4 ± 4.5 / 0.003 / 0.988 (0.971 to 0.995)*
UK (n= 19)
Height (cm) / 167.1 ± 10.6 / 167.0 ± 10.3 / 0.768 / 0.984 (0.960 to 0.994)*
Weight (kg) / 67.5 ± 11.4 / 68.3 ± 11.5 / 0.001 / 0.995 (0.987 to 0.998)*
BMI (kg.m-2) / 24.1 ± 2.3 / 24.4 ± 2.7 / 0.035 / 0.958 (0.895 to 0.983)*
Spain (n=21)
Height (cm) / 169.9 ± 8.1 / 169.7 ± 8.1 / 0.479 / 0.989 (0.974 to 0.996)*
Weight (kg) / 68.4 ± 14.0 / 68.6 ± 14.2 / 0.500 / 0.991 (0.979 to 0.997)*
BMI (kg.m-2) / 23.6 ± 3.8 / 23.7 ± 4.0 / 0.344 / 0.980 (0.952 to 0.992)*
Poland (n=20)
Height (cm) / 168.7 ± 10.1 / 168.5 ± 10.0 / 0.267 / 0.998 (0.996 to 0.999)*
Weight (kg) / 67.2 ± 13.4 / 68.2 ± 13.4 / 0.002 / 0.993 (0.983 to 0.997)*
BMI (kg.m-2) / 23.5 ± 3.3 / 23.9 ± 3.1 / 0.003 / 0.981 (0.955 to 0.993)*
Data presented as mean ± SD for self-reported and measured values. aPaired t-test was used for assessing differences between means of both methods. bIntraclass correlation coefficient (ICC) and c Pearson Product correlation coefficient (r) and their corresponding 95% confident intervals were used to assess the level of reliability between methods. *All P-values for ICC and Pearson correlation were significant at <0.0001.
Table S2. Bland-Altman analyses for self-reported and measured height, weight and BMI by country.
Variables / Bland-Altman / P-value*Absolute mean differences (LOA) / (%) Relative mean differences (LOA)
By country:
Ireland (n=20)
Height (cm) / 0.13 (-2.7 to 3.0) / 0.06 (-1.62 to 1.74) / 0.681
Weight (kg) / -0.43 (-2.8 to 1.9) / -0.5 (-3.7 to 2.6) / 0.121
BMI (kg.m-2) / -0.18 (-1.46 to 1.09) / -0.7 (-5.6 to 4.3) / 0.222
Netherlands (n=20)
Height (cm) / -0.16 (-2.4 to 2.1) / -0.11 (-1.44 to 1.22) / 0.521
Weight (kg) / -0.70 (-3.0 to 1.6) / -0.9 (-3.6 to 1.9) / 0.014
BMI (kg.m-2) / -0.18 (-1.19 to 0.82) / -0.7 (-4.4 to 3.1) / 0.129
Germany (n=19)
Height (cm) / 0.60 (-1.4 to 2.6) / 0.33 (-0.81 to 1.47) / 0.019
Weight (kg) / -0.86 (-4.8 to 3.1) / -0.9 (-6.3 to 4.5) / 0.076
BMI (kg.m-2) / -0.43 (-1.97 to 1.12) / -1.6 (-7.9 to 4.8) / 0.029
Greece (n=21)
Height (cm) / -0.36 (-2.2 to 2.9) / 0.20 (-1.29 to 1.69) / 0.223
Weight (kg) / -0.88 (-3.9 to 2.1) / -1.1 (-4.6 to 2.5) / 0.016
BMI (kg.m-2) / -0.41 (-1.49 to 0.67) / -1.5 (-5.2 to 2.2) / 0.003
UK (n= 19)
Height (cm) / 0.13 (-3.6 to 3.9) / 0.1 (-2.3 to 2.4) / 0.767
Weight (kg) / -0.77 (-2.52 to 0.98) / -1.2 (-3.7 to 1.4) / 0.001
BMI (kg.m-2) / -0.35 (-1.64 to 0.95) / -1.3 (-6.4 to 3.8) / 0.035
Spain (n=21)
Height (cm) / 0.19 (-2.2 to 2.6) / 0.11 (-1.32 to 1.55) / 0.478
Weight (kg) / -0.28 (-4.0 to 3.4) / -0.4 (-5.9 to 5.1) / 0.500
BMI (kg.m-2) / -0.17 (-1.69 to 1.36) / -0.6 (-7.3 to 6.0) / 0.343
Poland (n=20)
Height (cm) / 0.15 (-1.0 to 1.3) / 0.09 (-0.61 to 0.79) / 0.267
Weight (kg) / -1.0 (-3.4 to 1.4) / -1.5 (-5.6 to 2.5) / 0.002
BMI (kg.m-2) / -0.38 (-1.37 to 0.61) / -1.7 (-6.4 to 3.0) / 0.003
Data represent absolute and relative mean differences [SR - measured values] with their corresponding limits of agreements (LOA ±1.96 SD). *Paired t-test was used for assessing absolute differences between means of SR and measured values.