Fig. 3: Intraclass correlation coefficient (ICC) values for various nutrient intake measurements across different numbers of days.
From: Minimum days estimation for reliable dietary intake information: findings from a digital cohort
The x-axis represents the number of days, while the y-axis represents the ICC scores. Each subplot corresponds to a different nutrient, with boxplots showing the distribution of ICC scores computed from all possible combinations of days for each number of days on the x-axis. The horizontal red lines in each subplot denote the ICC threshold of 0.75 (good reliability) and 0.9 (excellent reliability). Boxplot colors represent different nutrient groups: blue for micronutrients, red for food groups, and green for macronutrients. Note that ICC does not generally reach 1 due to inherent within-subject variability.
