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Electromagnetically induced transparency (EIT) and Autler–Townes splitting (ATS) are two similar yet distinct phenomena that modify the transmission of a weak probe field through an absorption medium in the presence of a coupling field, featured in a variety of three-level atomic systems. In many applications it is important to distinguish EIT from ATS splitting. We present EIT and ATS spectra in a three-level cascade system, involving cold cesium atoms in the $35{S}_{1/2}$ Rydberg state. The EIT linewidth, γ _EIT , defined as the full width at half maximum of the transparency window, and the ATS splitting, γ _ATS , defined as the peak-to-peak distance between AT absorption peaks, are used to delineate the EIT and ATS regimes and to characterize the transition between the regimes. In the cold-atom medium, in the weak-coupler (EIT) regime γ _EIT  ≈  A + B ( ${{\rm{\Omega }}}_{c}^{2}$ + ${{\rm{\Omega }}}_{p}^{2})/{{\rm{\Gamma }}}_{{eg}}$ , where Ω _c and Ω _p are the coupler and probe Rabi frequencies, Γ _eg is the spontaneous decay rate of the intermediate 6P _3/2 level, and parameters A and B that depend on the laser linewidth. We explore the transition into the strong-coupler (ATS) regime, which is characterized by the relation γ _ATS  ≈ Ω _c . The experiments are in agreement with numerical solutions of the Master equation. Our analysis accounts for non-ideal conditions that exist in typical realizations of Rydberg-EIT, including laser-frequency jitter, Doppler mismatch of the utilized two-color Rydberg EIT system, and strong probe fields. The obtained criteria to distinguish cold-atom EIT from ATS are readily accessible and applicable in practical implementations.