Table 2 Research agenda

• To identify the optimal clinical criteria or criteria cluster allowing diagnosis of OA phenotypes.

• To validate the criteria used to define clinical phenotypes

• To develop robust clinical and biochemical tools for the diagnosis of OA phenotypes

• To implement OA phenotypes diagnosis in clinical practice

• To identify comorbidities of different OA subgroups

• To develop a phenotype-based strategy for the management of OA

• To implement a clinical phenotype approach in OA treatment development.

• To evaluate the efficacy of existing and innovative OA treatments according to patient phenotype to increase their efficacy.

• To elaborate guidelines for the management of OA based on clinical phenotype recognition.