How effective are alternative medications at lowering the use of illegal substances?

Answer, come up with ideas for 3a-e

Stats class

3. Design a study or experiment Survey 50 individuals who have completed treatment to determine drug of choice and how the alternative medication prescribed has impacted the use of illegal substances

3a. What type of sampling could you use? 3b. What are the variables? Which are explanatory and which are response? What type of measurement are they--quantitative or categorical? Nominal, ordinal, interval, or ratio?

3c. What are the possible counfounding variables? Are there possible placebo effects? Are blinds required? 3d. Is it experimental or observational? 3e. What type of design is it? Repeated measures, time series or cross-sectional?