244 Chapter 14: Sample Size convinced, and be able to convince others, that the study's potential benefits outweigh its potential risks. This in fact is the central consideration of the ethics committee 9 that will need to approve your research before it can be implemented. Following are some implications of this for study design: n n n Even less rigorous trials (e.g., exploratory studies) must have the potential to provide useful information--information that is sufficiently useful to outweigh the risks involved. Shoddy trials are not only bad policy, but they are also unethical. Given the resources available, you must plan the most scientifically sound trial possible. The number of patients participating in a trial--the trial's sample size-- must be optimal. If it is too small, the information provided will be negligible and not justify the risk. And if N is too large, you will have unnecessarily exposed more subjects to a new treatment than scientific rigor requires. Summary