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All three datasets make use of the SPTOBID variable to identify the tobacco product under study, and the IGDCMPID (ingredient or component identifier) variable to represent the ingredient name. IGDCMPID must be assigned by study sponsors to be unique with regard to the attributes that describe it. If, for For instance, if the same ingredient varies on one or more attribute (e.g., two different manufacturers supplied the same ingredient that is used in two different components of the product), IGDCMPID must be unique for each use to reflect this difference, even if they share the same common name, and/or the same IUPAC name and CAS Registry number. See IT dataset example which illustrates this below.
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