FAP and Familial adenomatous polyposis: However, FAP cases with mutations located within the classic mutation cluster had marginally lower performance on Woodcock-Muñoz summary scores of Cognitive Efficiency (p = 0.076) and Processing Speed, (p = 0.056), and on BRIEF-Adult scales of Shift (p = 0.058) and Initiate (p = 0.081) compared to FAP cases with mutations in the attenuated FAP region (Table 3).