  The mid-infrared (MIR) period-luminosity (P-L) relations for Cepheids will be
important in the JWST era, as it holds the promise of deriving the Hubble
constant within 2% accuracy. It is expected that the MIR P-L to be insensitive
to metallicity. In this work, we test this assumption of metallicity
independent of the IRAC band P-L relation by applying well-known statistical
methods to the synthetic P-L slopes from a series of pulsating models with
known metallicity. The statistical tests suggest that the P-L slopes in MIR are
linearly depending on metallicity.
