statistical research in chess?


There are plenty of statistics on openings and performance, but sound openings ultimately have little influence on the overall game results. The game is normally lost in the middlegame or endgame.
At lower levels, openings have very little influence, assuming the player doesn't fall into a trap or just play a bad opening.

Every database I know of will show you statistics like that.
However they can be misleading. For example a line may be popular for 10 years until 1 day a problem is discovered, and so everyone stops playing it... so statistics may say it's one of the best options when in reality it's one of the worst.
In the end, choosing an opening based purely on statistics is as bad as choosing openings based only on engine evaluations. These are only pieces to the puzzle. They're worth considering, but they're not the solution.

FWIW I recommend choosing an opening that many different GMs have played (past or present) and use the engine to make sure the lines you choose don't have any big mistakes (a persistent disadvantage of size 0.5 doesn't mean much, but if it's persistent and close to 1.00 then that's a problem).
Then play a lot of games... sometimes an opening is very good, but you'll have poor results until you've played it for a number of months and in many games. Don't quit an opening just because it's not brining immediate results. Be sure to reference databases for opening moves and GM games for middlegame ideas.
My two cents.