Researchers from a psychiatry department are examining the effectiveness of a new medication on moderate-to-severe symptoms of anxiety. The study requires volunteers who are at least 18 years old and in general good health and who are not taking oral medications for their anxiety. The study lasts 23 weeks. The researchers are offering a small payment as a compensation for participation.
Is this an ideal data collection method? Can the results be considered reliable? Can the gathered data be representative of the population?
Give two reasons to support or reject the method of recruiting volunteers to gather information in this statistical study.