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  : \[sim2\]Small sample of sizes $N = 22$ simulations ($10^4$ replications, $n_q=25$) from the D-vine copula mixed model and biases, root mean square errors (RMSEs) and standard deviations (SDs), along with the square root of the average theoretical variances ($\sqrt{\bar V}$), scaled by 100, for the MLEs of the main parameters of interest of the one-factor copula mixed model under different copula choices and margins. The true (simulated) D-vine copula mixed model uses a Clayton rotated by 270$^\circ$ and Clayton copula to join the (latent) sensitivity and specificity of the first and second test, respectively.

Cln{$\omega_1^\circ,\omega_2^\circ$}: The bivariate copulas are the Clayton rotated by $\omega_1^\circ$ and $\omega_2^\circ$ to handle the positive and negative dependencies, respectively.

From the table it is seen that the one-factor copula mixed model with normal (beta) margins led to unbiased and efficient estimates when the true model is the quadrivariate vine copula mixed model with normal (margins) when the bivariate copulas are a combination of Clayton and rotated Clayton by $270^\circ$ to model the the positive and negative dependencies, respectively. These are the same with the true (simulated) copulas of the D-vine copula mixed model which 