Effect Parameter Estimate Rounded to initial  value Fixed-effects parameters drug1 intercept β01 13.9102 13.91 drug2 intercept β02 -3.6667 -3.67 drug3 intercept β03 0.6853 0.69 drug1 slope β11 1.198 1.2 drug2 slope β12 1.5146 1.51 drug3 slope β13 1.3481 1.35 Variance parameters Random-intercept variance d 8.9976 9 Serial process variance τ2 3.4068 30.41 Serial process correlation ρ 1.000 1.00 Measurement error variance σ2 0.7423 00.74 p-value drug1 effect   0.0061   drug2 effect   0.6004

Table 3: Multi-centre data. Parameter estimates of the linear mixed model, used as initial values for the Diggle-Kenward model.