CHAPTER 7 182 pattern of children in the global low functioning profile was different to the cognitive strategy pattern in the other two profiles; low cognitive functioning with a moderate to normal ambulation (‘mixed’) and global moderate functioning. Due to the relatively small sample size, the difference is not robust enough to be statistical significant. However, it is comparable to the study of Sturkenboom et al [29] in people with Parkinson’s disease who found a statistically significant mean difference between two sub-groups. Overall, the findings in the current study show the clinical relevance of the PRPP-Assessment for heterogenic groups as it can measure high functioning and low functioning. Convergent validity was measured by calculating the rank-correlation between the COPM-performance score and the PRPP-Assessment mastery score, and resulted in a very low level of agreement. This finding suggests that the COPM-performance (parent rated) and PRPP-Assessment mastery score (therapist rated) may in fact be measuring different constructs. Prior to viewing the video-footage provided by parents, the researcher discussed the desired level of performance that would be deemed satisfactory by the child or their parents. Therapists used this criterion referenced approach as outlined by the PRPP scoring instructions[36]. In contrast, parents appeared to use a normative frame of reference when scoring the COPM. Parents used wording as; “he has trouble with participating, so I score every activity a 4”, or “she is not performing this activity as her peers, therefore I can’t score it a good mark”. It appears that the low level of agreement between ratings on the COPM and the PRPP-Assessment may be attributed to parents using a ‘normative’ frame of reference, while therapists used a ‘criterion’ frame of reference that characterizes the PRPP-Assessment. Although the researcher asked ‘how would you score performance taking into account the criterion we just formulated’, the common way in society is to compare children with other children which may have made it hard for parents to score performance against the criterion. Therefore, it is suggested to use more objective measures to establish convergent validity as recently performed by Nott and Chapparo[27]. A strength of using the PRPP-Assessment that was evident in the current study, was the self-selection of tasks by parents and/or children and tasks were meaningful. Self-Determination Theory, proven to be important in the meaningfulness of tasks for children with mitochondrial disorder[8], highlights the internal factors of autonomy and competence that can influence motivation for these tasks. In contrast to other activity-based assessments, tasks selected by parents represent five domains of the ICF-CY and all performance areas of the OPMA. In clinical practice with children with mitochondrial disorders, the Pediatric Evaluation of Disability Inventory (PEDI) [59, 60] is often used to gain insight in daily functioning.
RkJQdWJsaXNoZXIy MjY0ODMw