Thissen, G., van Middelkoop, M., Colaris, J., Selles, R., Dziedzic, K., Nicholls, E., & Bierma-Zeinstra, S. THE SUBGROUP EFFECTS OF NON-SURGICAL AND NON-PHARMACOLOGICAL TREATMENT OF PATIENTS WITH HAND OSTEOARTHRITIS - A PROTOCOL FOR AN INDIVIDUAL PATIENT DATA META-ANALYSIS IN THE OA TRIAL BANK