This is a relatively straightforward proposal and a good use of the data. However, before approval, the authors should closely review their submission – there were several grammatical errors and typos that should be corrected, some of which obscured the clarity of the writing (for instance, “In this study, we will not focus on one several predictors.”). In addition, and more importantly, the ‘Main Predictor/Independent Variable’, ‘Other Variables of Interest’ and ‘Statistical Analysis Plan’ sections do not seem to reflect the stated purpose of the study: to examine the association between patient BMI and efficacy of abiraterone acetate. I expected the entirety of the ‘Main Predictor/Independent Variable’ section to be about BMI and how it would be treated as a variable (continuous? categorized? how?). Similarly, I expected the ‘Other Variables of Interest’ section to list all the other variables that would be used for risk-adjustment (and how they would be treated as variables). Finally, the ‘Statistical Analysis Plan’ section makes no mention of examining associations with BMI nor risk-adjustment. Please clarify.