The KSVR vs. PSRR
the below is from TI
The supply rejection ratio, kSVR, is the same as the power supply rejection ratio, PSRR. It is defined as the absolute value of the ratio of the change in supply voltages to the resulting change in input offset voltage. Typically both supply voltages are varied symmetrically. It is expressed in dB.
The power voltage affects the bias point of the input differential pair. Because of the inherent mismatches in the input circuitry, changing the bias point changes the offset voltage, which, in turn, changes the output voltage.
For a dual-supply op amp, kSVR = DVCC�/DVOS or DVDD�/DVOS. The term DVCC� means that the plus and minus power supplies are changed symmetrically. For a single-supply op amp, kSVR = DVCC/DVOS or DVDD/DVOS. Also note that the mechanism that produces kSVR is the same as for CMRR. Therefore kSVR as published in the data sheet is a dc parameter like CMRR. When kSVR is graphed vs. frequency, it falls off as the frequency increases.