Figure 3

Matrix plot showing the bivariate distribution of the three primary rheumatology function tests (grip strength, walking velocity, timed button test, and the global physical function scale) for 779 patients with rheumatoid arthritis. The Pearson correlation coefficients of the global physical function scale with grip strength = 0.80, with walking velocity = 0.86, and with the timed button test = 0.85. All coefficients were significant at P ≤ 0.0001.