SDTM Example.Puff Topogaphy

This is a study where subjects were randomized to 3 different concentrations of e-nicotine liquid, or their usual brand of cigarettes. The subject used the product at home for 2 weeks. This 2-week period allowed subjects to become familiar with the e-cigarette. After two weeks, the subjects were confined to the clinical for one day. They were required to not use any tobacco products for 12 hours prior to the visit. Subjects had to have CO level below a pre-specified level, to attend the visit. If the level, was too high, the visit was re-scheduled. Subjects were instructed to take 10 puffs on the e-cigarette/usual brand of cigarettes in the morning and afternoon. Puff topography was measured in the morning and afternoon using the same device for all subjects. Subjects were not allowed to use any tobacco products between the morning and afternoon sessions. 

A  Study Reference domain, DI, was used to identify the device used to measure puff topography. This provides a consistent sponsor-defined variable (SPDEVID) for linking data. Device identifiers exist independently from subjects; therefore, the DI domain does not contain USUBJID. Only one device was used for all subjects in the study. 

The sponsor submitted the EX domain to represent the usage of the tobacco product. For each subject, the usage for the two week period are represented, and then the specified usage during the in-clinic visit are shown. The sponsor elected not to represent each puff in this EX dataset. Each Puff could have been recorded.       
The FAEX domain was used to represent the puff topography associated with the in-clinic visit. The Findings About Events or Interventions structure (or "FA structure") is used to represent collected data that are findings about” an event or intervention that cannot be represented within an event or intervention record or as a supplemental qualifier to such a record. Not all findings associated with an event or intervention should be represented in the FA structure.

A puff-by puff analysis was performed. FATPT was used to represent the time point, in this case, AM and PM. Typically, the sponsor derives summary results using the individual source data records; these summary results are represented in ADaM. However, if summary results are collected on a CRF or provided by an external vendor, these derived results can be represented in FAEX using the variable FACOLSRT. In this example, the sponsor created an ADaM dataset to represent the summary data ( Not Shown). 

The RELREC dataset was used to record the relationship between the Exposure records in EX and the records in FAEX.