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Description: Dietary fiber extension for the Food-pics_extended database The Food-pics database extended (Blechert et al. 2019) contains a multitude of standardized food stimuli, with extensive information including macronutrient information, yet fiber content is not available. Food category extension for the Food-pics_extended database To provide this information, we first added new standardized food categories to the Food-pics_extended database according to the WHO and Food and Agriculture Organization (FAO) “codex alimentarius” (https://www.fao.org/gsfaonline/foods/index.html) (table: food_pics_database_extended2016_food_types+fibre_content_curated.csv; column: type). Here, we excluded images no. 11 (cheese and cold meat platter), no. 150 and no. 294 (popcorn as it could be sweet or salty) due to ambiguity. We also excluded images no. 134 and no. 137 as they depicted the same chocolate muffin as in image no. 80, only from a different perspective, as well as no. 306 showing roast potatoes, which we found not clearly identifiable. Additionally, we unified the German naming of the stimuli (table: food_pics_database_extended2016_food_types+fibre_content.csv; column: Item_description_german_unified) as through original description, we could not identify all images depicting similar or identical food items. Dietary fiber extension for the Food-pics_extended database Fiber content of the remaining Food-pics stimuli no. 1 to 568 (n=562) was evaluated by four non-expert raters. These 562 stimuli were selected for further evaluation because of available macronutrient information. Dietary fiber reference nutritional information stemmed from various nutrition databases (e.g. FoodData Central App by the USDA, Swiss Food Composition Database or Food Database GmbH), online producer declarations and nutrition science books (Elmadfa et al. 2015). The respective sources of each rater and the derived fiber content per 100 grams are provided (table: food_pics_fibre_ratings_single_raters.csv; columns: “*_source”). Mean fiber per 100 g and per item across four raters was computed. Inter-rater reliability across four raters was good overall (using psych() intraclass correlations and two-way random effects models for single rater: ICC2 kappa = 0.76, 95% CI: 0.74, 0.79). Yet, to ensure plausibility of the fiber ratings, we checked those ratings with larger standard deviation than the mean across the four raters (n=44 items). The inter-rater variability in fiber ratings among these identified items was curated for some (n=9 items due to unreliable sources) and deemed valid nonetheless for all others (n=35 items) because of the following reasons: i) visual assessment only of the depicted item and its ingredients leading to an approximation of the exact ingredients (e.g. whole-grain or white flour in bakery items), ii) imprecision of matching the depicted food item to food database entry due to multi-component items (e.g. piece of layered caked or sushi rolls), or iii) variation in the databases for similar or identical items (e.g. Magnum Classic). After curation, inter-rater reliability across four raters improved slightly, but remained good overall (ICC2 kappa = 0.77, 95% CI: 0.75, 0.80). In order to add the fiber value to the original Food-pics_extended table, we also calculated the total fiber amount for the depicted food portion based on the provided portion size (grams_total). The calculation and exclusion process can be followed up in the table: food_pics_mean_fibre_rating.xlsx. On average, fiber content was high in ready-to-eat savories (such as nuts or pretzels), fruits and vegetables, and low in dairy & eggs, fish, meat and beverages (Table 1, also note the differences in SD range). How to cite: If you use the provided fiber ratings for the Food-pics_extended database, cite Medawar, Evelyn, Thieleking, Ronja, Witte, A. Veronica. “Dietary Fiber Extension for the Food-Pics_extended Database.” OSF. 2021. Original database: Blechert, J., Lender, A., Polk, S., Busch, N. A., & Ohla, K. (2019). Food-pics_extended—an image database for experimental research on eating and appetite: additional images, normative ratings and an updated review. Frontiers in psychology, 10, 307.