The Levada Center is funded by the National Endowment for Democracy (NED), which is known as a CIA cut-out. It is based in the US, at the University of Wisconsin Madison.

The NED is the "NGO" arm of the CIA. That is the agency that organises the colour revolutions. That is why the Levada Center is classified by the Russian government as a "foreign agent".

You can trust what they say.

https://www.ned.org/democracy-story/russia-polling-for-democracy-the-yuri-levada-analytical-center/