Thanks to everyone for some excellent discussion so far. Many have touched a bit on the idea of "cost effectiveness." While the cost of the Step 2 CS exam is quite clear, studies measuring its effectiveness are limited.
There are only 2 relevant studies to date. Winward et al. found a "modest" yet significant correlation between Step 2 CS interpersonal/communication scores & intern communication evaluations (ncbi.nlm.nih.gov/pubmed/235249...). More recently, Cuddy et al. found that Step 2 CS data interpretation score (based on written note) but not data gathering score (based on H&P) was correlated with intern H&P evaluations (ncbi.nlm.nih.gov/pubmed/263977...).
Furthermore, it's not entirely clear how to define "effective" in this setting. The lack of performance feedback limits the test's utility as an educational tool, but true purpose of a licensing exam is to protect patients by assuring all physicians meet minimum skills competencies.
My question is: How would one better study Step 2 CS to determine it's effectiveness? What is the "gold standard" for clinical & communication skills? What are the most appropriate outcome measures?