A clinical trial dataset contains multiple records per subject due to repeated measurements over time. You are tasked with summarizing the number of adverse events (AE) experienced by each subject, categorized by severity (Mild, Moderate, Severe), while accounting for the visit at which the event occurred. Which SAS procedure will allow you to obtain a summarized count of AEs by severity for each visit for all subjects?

During a clinical trial, data were collected on a nominal categorical variable indicating patients' blood type (Type A, Type B, Type AB, Type O). The goal is to analyze the distribution of blood types among patients who experienced an adverse event versus those who did not. Which of the following statistical methods BEST suits the objective of comparing the distribution of a nominal categorical variable across two independent groups?

You are working on a clinical trial data set in SAS, and you need to create a new variable that captures the number of days since the start of the study. The study start date is available as an automatic variable called `Study_Start_Date`, and each patient's visit date is recorded in a variable called `Visit_Date`. Which of the following code snippets correctly calculates the new variable `Days_Since_Start`?

Which key organization is responsible for oversight and approval of clinical trials in the United States, ensuring that they are conducted according to regulatory requirements to safeguard participant health and collect reliable data?

During a clinical trial data analysis, you intend to use a SAS automatic variable that contains the current date whenever the SAS code is executed. This will be utilized to flag all records from the clinical trial data set that have been captured after a certain cutoff date. Which of the following SAS automatic variables should be used to get the current date in a data step?