Study included 28 subjects (seven male and 21 female, age 18–65 years) completed the questionnaire and gave blood for testing peripheral blood mononucle

Study included 28 subjects (seven male and 21 female, age 18–65 years) completed the questionnaire and gave blood for testing peripheral blood mononuclear cells telomere length. So, in other words anecdotal evidence, and an interesting sidebar, but really just some notes about one type of tissue sample across 28 people. If it were any other look at any other tissue sample, what would you say about the sample size and the reliability of voluntary answers from subjects based on memory?