ABSTRACT
Validity and reliability are multifaceted and complex. This comprehensive chapter indicates how validity and reliability are defined and addressed in different approaches to, kinds of and methodologies in educational research, including quantitative, qualitative and mixed methods research. It sets out a range of different types of validity and how researchers can address and ensure them practically in both quantitative and qualitative research, at every stage of the research, from design and planning to conducting and reporting research. From commenting on several kinds of triangulation the chapter moves to discussion of different interpretations and ways of addressing reliability. The chapter moves to raising issues of validity and reliability in methods of data collection, including interviews, experiments, questionnaires, observations, tests, life histories and case studies.
