37 Development of a remote-use scale for monitoring mitochondrial disease in patients

Abstract

<h3>Aims</h3> This project aims to conceptualise, develop and validate an electronic patient-reported outcome measure for children with mitochondrial disease – Mitochondrial disease in Children, a patient Reported Outcome measure (MICRO). Children and families living with mitochondrial disease currently attend highly specialised centres where clinicians assess their disease using rating scales. Attending the clinic often involves long journey times, loss of school days, and associated safety risks for some of the severely affected children. Therefore, MICRO aims to empower families and carer to monitor their children’s condition independently and remotely at home as an alternative to face-to-face appointments. The project intends to correctly classify patients into <i>Mild</i>, <i>Moderate</i>, and <i>Severe</i> disease categories using scores generated from their MICRO scores. <h3>Methods</h3> MICRO development took place over three stages: Item Generation, Scale Development, and Scale Evaluation (figure 1). 1) Item Generation stage - Literature searches enabled the domain identification. A panel of laypersons (n=5) assessed the medical jargons used in a validated rating scale, the Newcastle Paediatric Mitochondrial Disease Scale (NPMDS). NPMDS data analyses (n=109) identified areas for development. Target Population input (focus groups, telephone interviews, questionnaires) were accompanied by longitudinal input from experts in the field of paediatric mitochondrial disease. 2) Scale Development stage – A small pilot (n=6) was conducted with a target population at the Newcastle NHS Highly Specialised Rare Mitochondrial Diseases Service Paediatric outpatient clinic. 3) Scale Evaluation stage – A validation study in clinic (n=20), where participants completed MICRO before undergoing assessment by current methods. A comparative analysis between the new MICRO and the existing NPMDS was undertaken. <h3>Results</h3> <h3>Item Generation</h3> 21 key NPMDS terms were identified as requiring development for layperson use in MICRO. Target populations also highlighted clinician/layperson linguistic differences, user interface concerns, and sensitivity of the language used to describe their children as important factors. Statistical analysis of NPMDS data excluded item ‘Blood’ from inclusion in MICRO on the grounds of infrequent scoring, and highlighted item ‘Growth’ as requiring revision to ensure participant completion, whilst items ‘Visual Acuity’ and ‘Ataxia’ were excluded due to lack of target population understanding. <h3>Scale Development</h3> Mean pilot item concordance with the NPMDS was 78.1±18.3%. No change in severity classification was reported in any participant. Participants reported no difficulty understanding or completing MICRO. Concordance was lowest in ‘Myopathy’, ‘Pyramidal’, ‘Extrapyramidal’ and ‘Neuropathy’ iteExpert review concluded that modification of these item descriptors was required. <h3>Scale Evaluation</h3> No significant difference (p&lt;0.001) was found between MICRO and NPMDS in identification of severity classification (Mild, Moderate, Severe). Mean item concordance was 83.4%±9.5%. Statistical analyses revealed strong correlations between both MICRO and NPMDS total raw scores and total percentages (figure 2). <h3>Conclusion</h3> The MICRO is a consistent and promising tool for the assessment and monitoring of paediatric mitochondrial disease. Our study has evidenced its comparable efficacy to the existing NPMDS. The target population also consider MICRO to be an acceptable, accessible and practical tool. This project has engaged the mitochondrial patient groups directly who welcome the opportunity to assess and monitor their child’s condition from home.