Els van de Vijver

16 Chapter 4 describes a further refinement of the formulated diagnostic test strategy of chapter 2, based on repeating the study in a separate and large validation cohort. We use an optimized cut off for calprotectin in combination with blood markers, and modify the inclusion criteria of the study cohort. Part II - Quality of life beyond clinical remission: Fatigue in paediatric IBD Treatment goals in IBD have changed considerably over the years. In the past, treatment was limited to controlling exacerbation, and it was aimed at alleviating clinical symptoms. The introduction of biological agents as anti-inflammatory therapy marked the beginning of a new era. Mucosal healing became the primary goal of treatment. The use of these agents have decreased rates of surgery and hospitalization.(17) In current practice, the focus of IBD treatment is typically on anti-inflammatory agents and therapies that modulate the immune system. However, many symptoms may not be directly caused by active inflammation, but may involve other mechanisms, including disease-associated symptom experience and psychological processes.(18) Moreover, the increasing recognition of, and appreciation for, the importance of health-related quality-of-life has spurred the use of such patient-important outcomes in clinical trials. Quality of life in IBD The World Health Organization defines quality of life as ‘an individual's perception of their position in life, in the context of the culture and value systems in which they live and in relation to their goals, expectations, standards and concerns’.(19) In IBD, stress and psychological health are likely to play an important role in symptom experience. For this reason, an exclusive focus on anti-inflammatory therapies is not expected to fully serve the needs of the patient. One important symptom that is frequently reported by IBD patients is fatigue. Fatigue Fatigue refers to a subjectively overwhelming sense of tiredness, lack of energy and a feeling of exhaustion that decreases an individual’s capacity for physical and mental activity.(20) It is Chapter 1