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. 2019 Jun 26;19:130. doi: 10.1186/s12874-019-0773-1

Table 3.

Results from M1 and M4. M1 is the joint model that shares both the random intercept and slope from the longitudinal sub-model with the random intercept from the survival model. M4 is the interval censored survival model with the longitudinal measurements as a time-varying covariate

M1: Shared Random Effects M4: Time Varying Covariate
Lower Upper Lower Upper
Parameter Estimate SD 95% CrI 95% CrI Estimate SD 95% CrI 95% CrI
Linear Sub-Model
b 0 7.24 0.06 7.12 7.36 - - - - -
b 1 -0.05 0.005 -0.06 -0.04 - - - - -
σe2 7.44 0.09 7.26 7.63 - - - - -
σ02 1.66 0.14 1.40 1.94 - - - - -
σ12 0.004 0.0006 0.003 0.005 - - - - -
ρ -0.38 0.07 -0.51 -0.24 - - - - -
Survival Sub-Model
α 0.57 0.06 0.47 0.69 α tvc 0.46 0.03 0.40 0.53
Hazard Hazard
Ratio Ratio
β 0 0.03 0.01 0.01 0.06 γ 0 0.17 0.06 0.08 0.30
β1 (HLA Mismatch Number) 1.26 0.07 1.13 1.40 γ 1 1.29 0.06 1.17 1.43
β2 (African American) 2.09 0.56 1.23 3.39 γ 2 1.79 0.40 1.11 2.70
β3 (Hispanic) 1.60 0.33 1.05 2.31 γ 3 1.67 0.31 1.14 2.33
β4 (Other Race) 1.14 0.56 0.34 2.41 γ 4 1.12 0.47 0.40 2.20
β5 (30-49 years) 0.57 0.15 0.32 0.93 γ 5 0.67 0.17 0.42 1.05
β6 (≥50 years) 0.30 0.08 0.17 0.49 γ 6 0.41 0.10 0.25 0.65
λ 0 0.64 0.06 0.52 0.75 η 0.80 0.03 0.75 0.85
λ1 (per 0.05 change) 0.43 0.07 0.32 0.58 - - - - -

For M1, the posterior mean and 95% credible intervals are presented for the linear portion of the model, the survival portion of the model, and the association parameters. The longitudinal portion is comprised of a fixed intercept (b0), a fixed slope (b1), and a random error term (N(0,σe2)). There is also a random intercept (a0iN(0,σ02)) and a random slope for each individual (a1iN(0,σ12)), which have a correlation parameter ρ. The survival model is comprised of fixed covariates (β), the Weibull association parameter α, and a random intercept for each individual that is related to the random intercept and slope of the longitudinal sub-model through two association parameters. The first association parameter (λ0) links the two sub-models through their shared random intercepts. The second association parameter (λ1) links the two sub-models through the longitudinal random slope and the survival random intercept. M4 contains the Weibull scale parameter, αtvc, baseline covariates with parameter γ, and the coefficient for the time-varying covariate, η