Table 4.

Considerations in the development of LanguaL™ Indexing System for dietary supplements

Consideration	Comment
Populating and maintaining dietary supplement databases is a time-consuming task, due to the large number of products that are introduced, modified, or relabeled each year in the U.S.A.	Since LanguaL™ can facilitate a standardized data cataloguing system, it can promote seamless sharing of data among database developers once label data has been entered, thus avoiding duplicative efforts.
Product type (Facet A), is a very important facet for researchers, since it captures what type of dietary supplement was consumed from dietary intake records. The proposed dietary supplement classification could be expanded to fully describe products based on their intended or primary use, e.g. bone health.	The narrow terms for Facet A were developed to be consistent with the definition of dietary supplements outlined in DSHEA, which is based on product composition. Additional “narrow” terms based on intended use could be added to Facet P. Consumer Use/Label Claims. This facet can thus be used to group products based on their intended use. However, manufacturers often list several uses for a product and the primary intended use might not be indicated or obvious, or differ from consumer use.
Problems arise when indexing dietary supplements that have multiple ingredients grouped under “proprietary formula” in the supplement facts panel. As dietary ingredients can affect the bioavailability of nutrients, the ability to identify all dietary ingredients in a database is considered an important feature for some researchers.	The practice of grouping ingredients under a “proprietary formula” is permissible under existing U.S. FDA regulations. However, this practice will not affect indexing nutrients that are of primary interest to NHANES, since only dietary ingredients without a Daily Value (DV) can be included in a “proprietary formula”. DVs are established by the U.S. FDA for labeling purposes.
It is difficult to include possibly significant details when indexing multi-ingredient dietary supplements.	There are two approaches to indexing multi-ingredient products: 1) Index the main ingredient by weight in facets B & C with the remaining ingredients listed in facet H. A drawback to this alternative is that only the main ingredient will have full information recorded. 2) Full ingredient indexing, with all ingredients indexed and listed in descending order by weight, so that full information retrieval can be achieved. The drawback to this alternative is that an additional system analogous to a recipe management system would be required.