title: Developing outcome measures for pediatric mitochondrial disorders: which complaints and limitations are most burdensome to patients and their parents?
abstract: Since some drug intervention effects are only experienced by the patient, organizations such as the Food and Drug Administration prefer clinically meaningful outcome measures. Here, we evaluated which symptoms and limitations in daily life are most burdensome to pediatric patients with mitochondrial disorders and their parents, using two questionnaires. In a study of 78 patients, the most burdensome complaints included fatigue, behavior and speech disturbances, epilepsy and muscle weakness and a high degree of limitations in daily activities was found. Importantly, there was a discrepancy between what symptoms metabolic pediatricians estimated would be most burdensome compared to the patients'/caretakers' opinion. To include feasible and relevant outcome measures in intervention studies, the experience and opinions of patients and caretakers should therefore be heard.
authors.affiliation: Radboud University Nijmegen Medical Centre, Nijmegen Centre for Mitochondrial Disorders, Department of Pediatrics, Geert Grooteplein 10, 6500 HB, P.O. Box 9101 Nijmegen, The Netherlands. S.Koene@cukz.umcn.nl
authors.forename: Saskia
authors.initials: S
authors.lastname: Koene
authors.forename: Saskia B
authors.initials: SB
authors.lastname: Wortmann
authors.forename: Maaike C
authors.initials: MC
authors.lastname: de Vries
authors.forename: An I
authors.initials: AI
authors.lastname: Jonckheere
authors.forename: Eva
authors.initials: E
authors.lastname: Morava
authors.forename: Imelda J M
authors.initials: IJ
authors.lastname: de Groot
authors.forename: Jan A M
authors.initials: JA
authors.lastname: Smeitink
mesh_terms: D000293:Adolescent; D002648:Child; D002675:Child, Preschool; D017281:Cost of Illness; D005260:Female; D006801:Humans; D007223:Infant; D008297:Male; D028361:Mitochondrial Diseases / Q000473:pathology / Q000523:psychology / Q000628:therapy*; D010290:Parents; D011795:Surveys and Questionnaires; D016896:Treatment Outcome