Cognition: development of a cognitive testing battery on the iPad for the evaluation of patients with brain Mets.

To make assessment of neurocognitive decline in patients with brain metastases more reliable and feasible, Brainlab AG developed an application 'Cognition' for the iPad by gamifying validated paper and pencil tests. This study aims at validating the computerized tests. We assessed reliability and comparability of 'Cognition' with similar well-established paper and pencil tests in two consecutive sessions per participant. The electronic tests used the same assignments with different stimuli than the paper and pencil tests. Domains involved are learning and memory, attention and processing speed, verbal fluency and executive functions. In total 5 employees and 25 cancer patients without disease in the CNS participated, of whom 24 completed both sessions. Reliability was found satisfying for the domains learning and memory (p = 0.08; p = 0.612; p = 0.4445) and verbal fluency (p = 0.064). A learning effect showed for attention and processing speed (p = 0.001) while executive functioning showed a significant decline, possibly due to radiotherapy-related fatigue (p = 0.013). Concerning comparability between electronic and paper results, a significant correlation was found for attention and processing speed (p = 0.000), for verbal fluency (p = 0.03), for executive functions (p = 0.000), but not for learning and memory (p = 0.41; p = 0.25). Overall 'Cognition' showed moderate comparability, probably caused by the consecution of tests during sessions and the unfamiliarity with electronic test in older patients. After improving its functionality, the application needs to be validated in patients with brain metastases before it can detect cognitive decline and possible early radiation toxicity or relapses.