A quantum integrability index was proposed in cite{KMS}. It systematizes the Goldschmidt and Wittens operator counting argument cite{GW} by using the conformal symmetry. In this work we compute the quantum integrability indexes for the symmetric coset models ${SU(N)}/{SO(N)}$ and $SO(2N)/{SO(N)times SO(N)}$. The indexes of these theories are all non-positive except for the case of ${SO(4)}/{SO(2)times SO(2)}$. Moreover we extend the analysis to the theories with fermions and consider a concrete theory: the $mathbb{CP}^N$ model coupled with a massless Dirac fermion. We find that the indexes for this class of models are non-positive as well.
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