Introduction

Quality improvement research strives to bridge the gap between ideal and actual care.1 Many paediatric diseases are rare, and thus there is insufficient evidence to define ‘ideal care’. Low prevalences and generally small patient numbers in centres in which children with rare diseases are treated create considerable barriers for clinical studies and for the development of evidence based guidelines. As a consequence, most existing guidelines are derived from studies in adults and lack any paediatric evidence.2 Here we focus on paediatric end-stage renal disease (ESRD) as an example of a clinical field in which these challenges are encountered.

In contrast to the situation in adults, ESRD in children is a rare disorder: in the Western world, the annual incidence rate of ESRD in patients <19 years of age is about 6–8 per million age related population. In a population of 3.9 million people below the age of 20 years in the Netherlands3 and 2.5 million in Belgium,4 this implies on average about 30 new patients per year in the Netherlands and 20 in Belgium. So that patients do not have to travel too far for treatment, there are four dialysis centres in the Netherlands and six in Belgium; consequently all dialysis centres are very small. ESRD in children is a serious and life-threatening disorder. Data on long term outcomes show that overall mortality in young adults is about 30 times increased5 6 and the risk for cardiovascular death is increased more than 100 times compared to an age related population.7 In survivors, juvenile ESRD has an important impact on somatic and psychosocial functioning in adult life: over 40% of the adult survivors of ESRD in children have daily somatic co-morbidity and about 20% are severely disabled.6 8 As compared to the general population, …