Cognitive Orientation to daily Occupational Performance (CO-OP; CO-OP approach) is a performance-based treatment approach for children and adults who experience difficulties performing the skills they want to, need, to or are expected to perform. CO-OP is a specifically tailored, active client-centered approach that engages the individual at the meta-cognitive level to solve performance problems. Focused on enabling success, the CO-OP approach employs collaborative goal setting, dynamic performance analysis, cognitive strategy use, guided discovery, and enabling principles. These elements, all considered essential to the CO-OP Approach, are situated within a structured intervention format, and may involve the parent/significant other as appropriate.

The Goal Attainment Scale (GAS) is a criterion--referenced measure used to quantify the degree to which personal goals are achieved. GAS methodology consists in:

• Defining a rehabilitation goal;
• Choosing an observable behaviour that reflects the degree of goal attainment;
• Defining the patient's initial level with respect to the goal;
• Ranging from a ''no change'' to a ''much better than expected outcome'');
• Evaluating the patient after a defined time interval;
• Calculating the overall attainment score for all the rehabilitation goals. A five-point scale will be used: "-2" is the initial pretreatment level; "-1" represents progression towards the goal without goal attainment; ''0'' is the expected level after treatment, (and therefore, the ''most likely'' level after treatment); ''+1'' represents a better outcome than expected; ''+2'' is the best possible outcome that could have been expected for this goal.

The Canadian Occupational Performance Measure is an individualized, client--centered, semi--structured interview used to identify occupational performance issues.For each performance issue, perceived performance and satisfaction are scored on a 1 to 10 Likert scale.

Performance and satisfaction are rated by children and parents on a scale of 1 to 10 (1= not at all able to perform the activity (performance) / not at all satisfied with the way the activity is performed (satisfaction); 10 = perfectly able to perform the activity (performance) / perfectly satisfied with the way the activity is performed (satisfaction). A difference of 2 points between pre- and post-intervention is clinically significant.

For each self--identified goal, four different COPM ratings will be obtained: (1) the participant's perceived occupational performance rating; (2) the participant's satisfaction rating; (3) the parent's perceived occupational performance rating; (4) the parent's satisfaction rating.

Behavioural Assessment of the Dysexecutive Syndrome for Children (BADS-C) predicts everyday problems associated with a major area of cognitive deficit that can impede functional recovery and the ability to respond to rehabilitation programs. The therapist can be use 2 subtests to assess the executive functions deficits (Zoo Part 1 and 2 subtest; Six parts subtest). Standard scores: mean 10 (SD: 3).