Juvenile Idiopathic Arthritis (JIA) is children's most common inflammatory rheumatic disease. The International League of Associations for Rheumatology (ILAR) defines it as a chronic arthritis condition that begins before the age of 16 lasts for six weeks or more, and has an unknown cause. Despite the gains made in the management of the disease of individuals with JIA with modern medical treatment methods, the physical and psychosocial problems caused by chronic inflammation negatively affect the daily living activities of individuals with JIA. On the other hand, in the JIA Core Set created by Outcome Measures in Rheumatology (OMERACT) in 2018, activities of daily living were included as a "mandatory area that should be evaluated in all studies." Therefore, to ensure that individuals with JIA reach a state of complete well-being, multi-interdisciplinary health professionals are expected to address the activities of daily living, identify the factors that limit these activities, and create intervention plans for the factors to be determined. The literature shows that the daily living activities of patients with JIA are addressed with a limited number of subjective measurement tools. However, these methods have disadvantages due to their subjectivity. In this case, objective measurement methods are needed to quantify the physical performance of patients with JIA in terms of their daily living activities. The Glittre Activities of Daily Living Test, initially developed by selecting activities similar to daily living activities to evaluate functional capacity in pulmonary diseases, has the potential to address this gap. Since the activities in the test require using both the lower and upper extremities, it has the advantage of reflecting functional capacity and providing information about performance in daily life activities. Although it has potential, the Glittre Activities of Daily Living Test needs appropriate psychometric properties for clinical settings and research for JIA patients. To our knowledge, no studies have been conducted in the current literature on the validity and reliability of the Glittre Activities of Daily Living Test in JIA patients. Therefore, this study aimed to evaluate the test-retest reliability, construct validity, and minimum detectable change of the Glittre Activities of Daily Living Test in assessing activities of daily living in children and adolescents with JIA.

Juvenile Idiopathic Arthritis (JIA) is children's most common inflammatory rheumatic disease. The International League of Associations for Rheumatology (ILAR) defines it as a chronic arthritis condition that begins before age 16, lasts six weeks or more, and has an unknown cause. Despite the gains made in the management of JIA patients with modern medical treatment methods, there are physical and psychosocial problems caused by chronic inflammation. While chronic pain, disease activity, fatigue, and musculoskeletal problems constitute the physical dimension of these effects, issues such as anxiety, depression, central sensitization of pain, decreased peer interaction, physical activity, and school participation constitute the psychosocial dimension. In a study that addressed these biopsychosocial problems holistically within the framework of the International Classification of Functioning Disability and Health - Children and Youth (ICF-CY), it was emphasized that the daily living activities of individuals diagnosed with JIA were negatively affected, resulting in participation restrictions in various environments. On the other hand, in the JIA Core Set created by Outcome Measures in Rheumatology (OMERACT) in 2018, activities of daily living were included as a "mandatory area that should be evaluated in all studies." Therefore, to ensure that patients with JIA reach a state of complete well-being, multidisciplinary health professionals are expected to address the activities of daily living, identify the factors that limit these activities, and create intervention plans for the factors to be determined. The literature shows that the daily living activities of patients with JIA are addressed with a limited number of subjective measurement tools, especially the Childhood Health Assessment Questionnaire (CHAQ). CHAQ, widely used in evaluating daily living activities in pediatric rheumatology, stands out with its advantages, such as being practical, short, easy to score, and providing a commonly spoken language due to its adaptation to many languages. However, CHAQ also has some disadvantages. These disadvantages are that CHAQ is known for its ceiling effect, its subjective aspect, and its relative insensitivity to short-term changes. Physical function is a complex and multidimensional phenomenon associated with the ability to move and perform daily activities. Measuring physical function is essential to provide targets for clinical intervention to reduce impairments and increase participation in activities. By assessing physical function, baseline function can be objectively determined before treatment, which is essential for evaluating the effectiveness of the intervention. Physical function is usually measured with physical performance tests and self-report questionnaires. Physical performance tests quantify performance, as opposed to the perception of performance obtained through self-report questionnaires, thus providing a more objective measure of actual functional capacity. Performance-based measures have theoretical advantages over self-report measures, such as better repeatability, greater sensitivity to change, and less influence by external influences such as culture, language, and education. The "Glittre Activities of Daily Living Test," a physical function-based test that objectively evaluates daily living activities, was initially developed by selecting activities similar to daily living activities to assess functional capacity in Chronic Obstructive Pulmonary Disease. Since the activities in the Glittre Activities of Daily Living Test require using both the lower and upper extremities, the test has the advantages of reflecting functional capacity and providing information about performance in daily living activities. Due to these advantages, reliability and validity studies have been conducted on diseases other than chronic obstructive pulmonary disease, which was the starting point. The Glittre Activities of Daily Living Test rules were initially developed for adult patients and modified because they were unsuitable for the pediatric group. The modified test, the Pediatric Glittre Activities of Daily Living Test, was valid and reliable in children aged 6-14. One of the primary treatment goals is to ensure that patients with JIA maintain their daily living activities. Activities of daily living are also considered an important outcome measure for evaluating the course of the disease and the effectiveness of treatment. When the literature is examined, self-reporting questionnaires are used more frequently to assess the daily living activities of JIA patients, and performance-based standardized measurement methods are used less frequently. When considering the needs of individuals with JIA, the Glittre Activities of Daily Living Test has significant potential in this disease group. However, its psychometric properties must be appropriate in clinical settings and research. To our knowledge, no studies on the validity and reliability of the Glittre Activities of Daily Living Test in JIA patients have been conducted in the current literature. Therefore, this study aimed to evaluate the test-retest reliability, construct validity, and minimum detectable change of the Glittre Test of Activities of Daily Living in assessing activities of daily living in children and adolescents with JIA. Since the test is modified for 6-to 14-year-olds, the "Pediatric Glittre Activities of Daily Living Test" reliability and validity will be assessed in individuals with JIA within this age group. The standard version will be used for JIA patients between 15 and 18.

Inclusion Criteria:

• Being diagnosed with Juvenile Idiopathic Arthritis (JIA) according to The International League of Associations for Rheumatology (ILAR) classification
• Being between the ages of 8-18
• Volunteering to participate in research

Exclusion Criteria:

• Advanced heart/lung/liver/kidney disease, neurological disease and malignancies
• Having undergone major orthopedic surgery
• Not volunteering to participate in the study

The study population will consist of individuals with JIA who meet the inclusion criteria at the Department of Pediatrics, Division of Rheumatology, Hacettepe University Faculty of Medicine.