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Reliable detections of Earth-sized planets in the habitable zone remainelusive in the Kepler sample, even for M dwarfs. The Kepler sample was oncethought to contain a considerable number of M dwarf stars ($T_\mathrm{eff} <4000$ K), which hosted enough Earth-sized ($[0.5,1.5]$ R$_\oplus$) planets toestimate their occurrence rate ($\eta_\oplus$) in the habitable zone. However,updated stellar properties from Gaia have shifted many Kepler stars to earlierspectral type classifications, with most stars (and their planets) now measuredto be larger and hotter than previously believed. Today, only onepartially-reliable Earth-sized candidate remains in the optimistic habitablezone, and zero in the conservative zone. Here we performed a new investigationof Kepler's Earth-sized planets orbiting M dwarf stars, using occurrence ratemodels with considerations of updated parameters and candidate reliability.Extrapolating our models to low instellations, we found an occurrence rate of$\eta_\oplus={8.58}_{-8.22}^{+17.94}\%$ for the conservative habitable zone(and ${14.22}_{-12.71}^{+24.96}\%$ for the optimistic), consistent withprevious works when considering the large uncertainties. Comparing theseestimates to those from similarly comprehensive studies of Sun-like stars, wefound that the current Kepler sample does not offer evidence to support anincrease in $\eta_\oplus$ from FGK to M stars. While the Kepler sample is toosparse to resolve an occurrence trend between early and mid-to-late M dwarfsfor Earth-sized planets, studies including larger planets and/or data from theK2 and TESS missions are well-suited to this task.

No Evidence for More Earth-sized Planets in the Habitable Zone of Kepler's M versus FGK Stars