Tartrate-resistant acid phosphatase-positive cells increased between weeks 0 and 52 ( RSG , 2.9 2 to 14.0 3 U/L , P = .001 ; MET , 3.3 2 to 16.7 2 U/L , P = .001 ) , increasing further in the RSG group after changing to MET ( to 26.5 5 U/L , P = .05 vs wk 52 ) .