The questionnaire was validated by interviewing approximately 20 customers with the aim of detecting comprehension problems and to assess if the questions responded to the research aims. The instrument consisted of 22 questions: 21 multiple choice and 1 open ended question. Multiple responses were allowed for the following items: 1) Respondent symptoms provoking self-medication,
2) Reasons for self-medicating, and 3) Locations where respondents purchased antibiotics for self-medicating.