  We study the kinematics of a sample of classical Cepheids younger than 120
Myr. For these stars, the estimates of distances taken from Skowron et al.,
which are based on the period-luminosity relation, and the line-of-sight
velocities and the proper motions from the Gaia catalog are available. There
are also distance estimates derived from the trigonometric parallaxes contained
in the Gaia ERD3 catalog. A method, which relies on comparison of the
first-order derivative of the Galactic rotation angular velocity, showed the
need to lengthen the distance scales determined by Skowron et al. by about 10%.
This conclusion was confirmed by direct comparison to the distances predicted
on using the trigonometric parallaxes. With taking into account this result, we
obtained new estimates of the Galactic rotation parameters and the parameters
of a spiral density wave.
