People often ask me about Step 1 corrections, particularly with regards to the Free
150 120 (for which I’ve posted explanations for several years). The data I’d come across over the years was super old.
Last month, Reddit user Waygzh posted the results of a 208 person survey (with an above average mean score of 245), which includes correlations for UWorld, the Free 150, multiple NBMEs etc.
The spreads are huge and the correlations not particularly good, but it’s the best you’re likely to get. Just don’t get discouraged if the number you see isn’t the number you want. Inspiration is better than deflation.
UPDATE: There’s now a 2017 Reddit survey available here as well.