Body Surface Area of Involvement (BSA)

This example shows the percentage of body surface area (BSA) affected by plaque psoriasis for a subject at each visit. The psoriasis condition itself is considered a clinical event; the evaluations of percentage BSA affected at specific time points were considered findings about the clinical event. Sponsors may represent findings data in a single FA dataset or split the FA domain into separate datasets, following guidance in the SDTMIG. In this example, an FACE dataset was used. A parent record in the Clinical Events (CE) domain is not required. The test, percentage BSA affected, is used where FAOBJ represents the disease of interest.

The palm method was used to determine the total area of involvement; this method is frequently used in psoriasis studies. An individual's hand, with or without digits, accounts for a small proportion of the total body surface. An individual's palm (not including fingers and wrist) accounts for about 0.5% of the individual's total body surface area. The entire palmar surface (including digits) accounts for about 1% of the individual's total body surface area. (CDISC Controlled Terminology). 

FALOC was populated with "SKIN" to indicate that all disease locations on the skin of the body were included. If the sponsor were to assess the BSA involvement on a specific body location, FALOC could be used to specify the location of interest. 

Because no parent record was included in CE, a RELREC dataset is not provided to link the FA domain to the parent domain.