[LONGITUDINAL]
input = {V, k, b}
EQUATION:
D=100
f = D/V*exp(-k*t)

[INDIVIDUAL]
input = {V_pop, omega_V, w, w_pop}
EQUATION:
V_pred = V_pop*(w/w_pop)
DEFINITION:
V = {distribution = lognormal, prediction = V_pred, sd = omega_V}

[COVARIATE]
input = {w_pop, omega_w}
DEFINITION:
w = {distribution = normal, mean = w_pop, sd = omega_w}