Tower of London (ToL) is a neuropsychological method for assessing planning ability. In this study, we attempted to introduce a shorter version of ToL. Two studies were carried out. In Study 1, patients with mild cognitive impairment due to Parkinson's Disease (n = 36) and a control group (n = 225) were included in order to select a suitable short version of ToL for Study 2. In Study 2, patients with schizophrenia (n = 30) and a control group (n = 31) were included in order to assess psychometric properties of the shortened version of ToL. Based on psychometric evaluations in Study 1, we offered three possible shortened versions. In Study 2, all three shortened versions proved to have good discriminative validity in our schizophrenia sample, but interestingly not in the healthy sample. We concluded that the use of shortened ToL is possible in specific psychiatric/neurological patient groups, although we do not recommend doing so in healthy individuals.
Keywords: Tower of London; executive functions; neuropsychological assessment; planning ability; problem solving; short version.