Efficacy of Computer-assisted Cognitive Remediation in Patients With Schizophrenia

Primary outcomes

1. Change of Wisconsin Card Sorting Test Score

   Time frame: Baseline, after completion of half of the programme (an average of 6 weeks), one month post-treatment

   It is a neuropsychological test that is used to measure high-level cognitive processes as attention, perseverance, working memory, abstract thinking, cognitive flexibility, and set shifting.

   The test consists of 128 card designs, participant is required to sort the cards under the categorization rules and feedback from examiner in about 20 minutes. The more categories achieved (range 0 to 6) and less perseverative errors (out of 128 trials) the better executive control. Moreover, the lower the total number of trials administered (total number of cards used) reflects greater efficiency of the participant in the task; in addition, the greater the total number of correct responses (number of successes in combinations according to the category) and the lower the total number of errors (number of incorrect combinations) also indicate the better the participant's performance.

2. Change of The Digit Span Test Score (Digit Span Forward and Digit Span Backward)

   Time frame: Baseline, after completion of half of the programme (an average of 6 weeks), one month post-treatment

   It measures a participant's attention and working memory. Forward span captures attention capacity and backward span reflects working memory. The higher both the scores the better functioning. Participant repeats or reverses the digit sequencing after the examiner read out lists of random numbers, extra digit would be added for increased level of difficulty with two trials per level until the participant gives out incorrect answer. Average adult score for forward span is eight to ten and seven to nine for backward span.

3. Change of Cognitive scores in the cognitive remediation programme CogniPlus®

   Time frame: Through study completion, an average of 12 weeks

   There are 15 individual training modules that grouped into 6 function dimensions (attention, neglect/visual field training, memory, executive function, spatial processing and visuomotor skills) in this programme.

   Different number of difficulty levels and specific requirements are structured in different modules. For example, DATEUP module in memory dimension contains 25 levels, incremented with increasing number of stimuli that move in higher speed for the participants to retain and update the information; while ALERT module in attention dimension have 18 difficulty levels, with decreasing maximum permitted reaction time for the participants to respond.

   For the evaluations of results in all modules, the higher percentage of correct response, the shorter reaction/working time and the higher difficulty level attained indicate the better corresponding functioning. The importance of these cognitive scores is to help tracking the participants' task functioning throughout the study.

4. Change of Role Functioning Scale

   Time frame: Baseline, after completion of half of the programme (an average of 6 weeks), one month post-treatment

   It is a measure of functioning level of adults in four domains: working productivity, independent living/self-care, immediate social network relationships and extended social network relationships.

   7-point scale for the four domains and their total score (ranging from 4 to 28) represent the Global Role Functioning Index, the higher scores the better the person's functioning.