Table 5. Baseline and interval scores with paired t tests for cognitive tests.

	Brixton	FAB	Hayling A	Hayling B	ACE-R
Baseline	2.8	11.7	12	12.5	79.7
Interval	2.7	11.7	11.9	12.9	76.6
t (df)	0.3 (15)	0.4 (14)	0.08 (15)	-0.7 (15)	1.9 (15)
p value	0.8	0.7	0.9	0.2	0.04

Mean baseline and interval scores are given. FAB is the frontal assessment battery, Hayling A is the number of category A errors in the Hayling test, and Hayling B the number of category B errors. ACE-R is the Addenbrooke’s Cognitive Examination Revised. The scores for Hayling A errors and Hayling B errors are given untransformed, therefore a higher score indicates more errors and therefore deteriorating function. t is the t statistic, df is the degrees of freedom, p values given are one tailed. The p value for which differences in baseline and interval scores would be significant using the Bonferroni correction for 5 comparisons is p<0.01. None of the cognitive tests are significant at this level.