  Linearizing the appropriate kinetic equation we derive general response
functions including selfconsistent mean fields or density functionals and
collisional dissipative contributions. The latter ones are considered in
relaxation time approximation conserving successively different balance
equations. The effect of collisions is represented by correlation functions
which are possible to calculate with the help of the finite temperature
Lindhard RPA expression. The presented results are applicable to finite
temperature response of interacting quantum systems if the quasiparticle or
mean field energy is parameterized within Skyrme - type of functionals
including density, current and energy dependencies which can be considered
alternatively as density functionals. By this way we allow to share
correlations between density functional and collisional dissipative
contributions appropriate for the special treatment. We present results for
collective modes like the plasmon in plasma systems and the giant resonance in
nuclei. The collisions lead in general to an enhanced damping of collective
modes. If the collision frequency is close to the frequency of the collective
mode, resonance occurs and the collective mode is enhanced showing a
collisional narrowing.
