认知功能评估的工具

Trail Making A and B
Purpose – to assess motor speed and mental flexibility Description – part A (motor speed) • the subject is shown a piece of paper or a computer screen with the numbers 1?5 located randomly • the task is to join the numbers in ascending order as quickly as possible – part B (set shifting) • as part A but the screen contains both numbers and letters • the task is to connect letters to numbers alternately in ascending order as quickly as possible • assessed as the time to complete each part of the test • time to administer: 5?0 min
The Wide Range Achievement Test (WRAT)
Purpose – to determine reading scores compared with years of education before onset of symptoms Description – similar to NART but includes tests of mathematical and spelling skills – has IQ and education equivalent scores and percentile scores – time to administer: 5?0 min
The Dot Test
Purpose – to assess visuo-spatial memory Description – the subject is allowed to see a sheet with a single dot for a short period – after a delay of 5, 10 or 15 s the subject is asked to show where the dot was – results measured as the average distance between the true and indicated position of the dot – time to administer: 15 min
Rey Auditory Verbal Learning Test (RAVLT)
Purpose – to assess serial learning and delayed recall Description – similar to the CVLT except • word list not conceptually categorised • no prompted recall condition – assessed as • number of words learned over five trials • proportion of information learned immediately that was recalled after a delay (delayed recall) • recognition discrimination – time to administer: 15 min + 20 min delay
Phonological Fluency and Category Fluency (e.g. FAS Test)
Purpose – to assess ability to produce words according to a characteristic (e.g. first letter) Description – the subject is asked to say as many words as possible beginning with a specific letter (usually F, A or S) in 1 min – sometimes specific categories are asked for (e.g. animals) – assessed as the number of correct words – time to administer: 3 min
Giessen simple motor mazes
Purpose – to assess visuo-motor coordination Description – the subject has to guide a dot through a maze on a computer screen – the maze has no blind alleys or decision points – the task must be completed as quickly and accurately as possible – assessed as • the length of the route chosen • time to complete • velocity (time relative to the length of route) • errors (number of times the walls are hit) – time to administer: 5?0 min
The California Verbal Learning Test (CVLT)
Purpose – to assess serial learning and recall Description – the subject is given five trials to learn a 16-item list containing items from four conceptual categories (fruits, spices, clothing, tools) – the subject is given a single trial to learn a different list – the subject then has to • recall the first list again • undertake a choice recognition test and identify words from the first list – time to administer: 20 min + 20 min delay
The Continuous Performance Test (CPT)
Purpose – to assess the ability to respond to target stimuli but not to non-target (noise) stimuli Description – the subject is told or shown a target signal to respond to – the subject is presented with a stream of stimuli, 10?0% of which are the target – difficulty can be varied by • degrading the stimuli • making the target more complex (e.g. complex sequwenku.baidu.comnces rather than single images) • adding extra simultaneous tasks – assessed as number of missed targets and number of incorrect responses – time to administer: 7?0 min
The National Adult Reading Test (NART)
Purpose – to assess differential deficits across cognitive domains Description – a word recognition reading test using phonologically irregular words – measures information acquired before onset of symptoms – provides percentile scores that allow comparison with other tests – time to administer: 5?0 min
The Letter-Number Span Test
Purpose – to examine the subject抯 ability to retain and perform 抯 low-level categorisation and sequencing of numbers and letters Description – a list of letters and numbers is read to the subject in random order – the subject has to arrange the numbers and letters in ascending order – progressively longer lists are given – results measured by the number of trials successfully completed – time to administer: 20 min
The values of tests of cognitive function
In patients with schizophrenia, standardised neuropsychological tests can be used to –predict overall functional outcome –assess response to treatment
The Wisconsin Card Sorting Test (WCST)
Purpose – to assess executive function Description – the subject is given four key cards with symbols varying in colour, shape and number of items – the subject is then asked to match a set of target cards to the key cards – the subject is told whether each match is right or wrong – as the test progresses the matching rules are changed (without the subject抯 knowledge) 抯 – various indices are available, including the number of categories completed – time to administer: around 20 min, depending on subject抯 pace 抯