  Critical examination is made on the relation between the mass shift of vector
mesons in nuclear medium and the vector-meson $-$ nucleon scattering length. We
give detailed comparison between the QCD sum rule approach by two of the
present authors (Phys. Rev. {\bf C46} (1992) R34) and the scattering-length
approach by Koike (Phys. Rev. {\bf C51} (1995) 1488). It is shown that the
latter approach is mortally flawed both technically and conceptually.
