pilot studies

• the pilot study is a small scale trial run of the actual investigation. a pilot study may involve a handful of participants rather than a total number in order to test the procedure and check the investigation runs smoothly. pilot studies are also used in questionnaires or interviews which can be used to ask questions in advance to make sure they are unambigous. in observational studies, a pilot study provides a way of checking coding systems before the real investigation.
• participants are sometimes not told the aim of the research at the beginning of a study. also, details may be kept from the participants such as which condition of the experiment they are in. this is known as a single blind procedure and is an attempt to control for the confounding effects of demand characteristics
• in a double blind procedure, neither the participant nor the researchers who conducts the study is aware of the aims of the investigation. double blind procedures are important for drug trials. treatment is adminstered to patients by a third party but does not know which drugs are real or placebos