Saemeh Arabahmadi - Department of English Language Teaching, Aliabad Katoul Branch, Islamic Azad University, Aliabad Katoul, Iran
Seyyed Hassan Seyyedrezaei - Department of English Language Teaching, Aliabad Katoul Branch, Islamic Azad University, Aliabad Katoul, Iran

Mixed methods research has become popular as the newest development in research methods and in approaches to mixing quantitative and qualitative research. It is believed that validity is not a property of a test or assessment but the degree to which we are justified in making an inference to a construct from a test score. Since mixed methods research involves merging supplementary strengths and non-overlapping weaknesses of quantitative and qualitative research, in this way assessing the validity of findings is particularly complex in mixed methods. So the main purpose of this study is to develop an understanding of validity in mixed method research. To do so this article presented further discussions of validity in mixed methods by introducing Dellinger and Leech (2007) validation framework. It was based on Messick’s (1989, 1995) ideas about construct validity for assessing validity in mixed methods research. Elements of their VF are described in details. Then the researchers discuss traditional terminology of validity for quantitative research by reviewing Hughes (1989) and Cronbach and Meehl (1995) definition of validity. For qualitative research as well Lincoln and Guba (2005), Wolcott (1990) perspectives on validity has been reviewed. Recent terminology of validity for mixed methods research was reviewed by two frameworks of Teddlie and Tashakkori (2003) and Onwuegbuzie and Johnson (2006). Therefore, the various ways of boosting the validity of the data are delineated at length. Finally, a brief discussion over the rational for unified validity framework is provided.

Validity; Construct Validity; Mixed Methods Research