To the Editor: In a randomized clinical trial assessing the effects of a 24-week physical activity intervention on cognition, Dr Lautenschlager and colleagues1 reported a significant difference in performance on their primary outcome measure. However, the numbers in the published tables are inconsistent, raising concerns that the reported significant finding may be attributable to baseline differences in the initial cognitive state of the 2 groups.
Mortimer JA. Physical Activity and Cognitive Function in Alzheimer Disease. JAMA. 2009;301(3):272-274. doi:10.1001/jama.2008.1010