1. move assumptions out of all of the examples

2. add row captions to highlight exceptions/assumptions

This is an example showing trial design and results from the in vitro bacterial reverse mutation test of Study #8325064. The bacterial reverse mutation test uses four different amino acid-requiring strains of Salmonella typhimurium (S. typhimurium) and one strain of Escherichia coli (E. coli) to detect point mutations, which involve substitution, addition or deletion of one or a few DNA base pairs. The principle of this bacterial reverse mutation test is that it detects chemicals that induce mutations which revert mutations present in the S typhimurium and E. coli tester strains and restore the functional capability of the bacteria to synthesize an essential amino acid. The revertant bacteria are detected by their ability to grow in the absence of the amino acid required by the parent tester strain.

• Assumption:  When the experimental unit is derived from the species and strain, such as a cell line, then TESTSYS should be supplied.

In this example, the Trial Summary dataset, ts.xpt, includes many informational fields that may provide context at the study level, for Study 8325064.  Also, TSGRPID has been used to link records (name, location, country) related to the test facility (TSGRPID = 1) and records related to the Test Site (TSGRPID = 2). The Study Director is associated with the Test Facility and the Principal Investigator is associated with the Test Site. Finally, the Primary Treatment CAS Registry Number is not known and this is recorded as an empty TSVAL and UNKNOWN in the corresponding TSVALNF.

This example trial set dataset shows information about the test conditions for SetA and SetR in this example study. For brevity, this does not show information for SetF, SetG, or any other sets.  A fully formed tx.xpt for this example study would include information about the test conditions for all sets. 

Observational Unit Identifiers (OBUIDs) are defined by the sponsor to uniquely identify the observational unit within an experimental unit. In this example the sponsor chose to define the EUIDs based on trial sets (e.g., F) and OBUIDs based on the position of the tube in one of multiple exposure/incubation plates (e.g, 6_1 for plate 6, position 1).