Objective: Several effective pharmacologic treatment options for polyarticual juvenile idiopathic arthritis (JIA) have emerged but initial treatment is heterogeneous in Germany. Therefore, the German Society of Pediatric Rheumatolgy has established a commission to develop consensus "Protocols on classification, monitoring and therapy in children's rheumatology (PRO-KIND)" to harmonize diagnostic and treatment approaches for new-onset JIA in Germany.

Methods: A set of definitions for in- and exclusion, diagnostic workup, parameters for the evaluation of disease activity criteria, therapeutic options, medication dosing, monitoring recommendations, _targets, definitions of a therapy failure and four therapeutic algorithms developed by a working group were agreed by web based survey to which all members of the GKJR have been invited. A final protocol with 4 consensus treatment plans (CTP) was agreed in a face-to-face consensus conferences employing modified nominal group technique.

Results: The initial 17 definitions and recommendations for new-onset polyarticular JIA agreed by the working group reached >80% agreement in a web survey in 68 German paediatric rheumatologist. Four CTPs were developed based on treatment strategies for the first 12 months of therapy, as well as definitions for clinical and laboratory monitoring. The CTPs include a step-up plan (nonbiologic Disease-modifying antirheumatic drug [DMARD] followed by a biologic), a combination plan (combination of nonbiologic and biologic after failure of initial DMARD), an intensive pulse corticosteroid scheme in parallel with a DMARD followed by combination therapy and a multiple corticosteroids joint injections strategy in a treat to _target approach. Step up will be guided by a treat to _target strategy to reach a JADAS-improvement at month 3, acceptable disease at month 6 or 9 and JADAS remission or at least JADAS minimal disease activity at month 12.

Conclusion: Standardized baseline work-up, disease activity evaluation and a definition of a treat to _target approach will result in better health outcomes for polyarticular JIA patients. Four CTPs were developed for new-onset polyarticular JIA, which coupled with data collection at defined intervals will be evaluated and improved to optimize management of polyarticular JIA. Harmonization of treatment will be the basis for future comparative effectiveness research.