Triangulation

by

James Drisko

• LAST REVIEWED: 25 May 2011
• LAST MODIFIED: 25 May 2011
• DOI: 10.1093/obo/9780195389678-0045

Introduction

The origins of triangulation in social work and in the wider social sciences are only metaphorically related to the process in geometry by which a point’s location is established by measuring angles and distances to it from two previously established points. This procedure is widely used in surveying to mathematically establish an unknown point in two dimensions. Still, this original geometric form of triangulation may be found in some social science community mapping efforts. In social work and social science publications related to family treatment, triangulation may refer to patterns of family and interpersonal interaction rather than research methods. In terms of research methodology, triangulation in social science refers to efforts to corroborate or support the understanding of an experience, a meaning, or a process by using multiple sources or types of data, multiple methods of data collection, and/or multiple analytic or interpretive approaches. The concept has roots in the conceptualization of quantitative research methods. Quantitative methodologists argued that establishing validity requires both a multiple-method and a multiple-trait approach. Establishing validity, therefore, requires the convergence of results achieved by differing methods and with differing variables. This initial concept was known as multiple operationalism. In sociology, an early integration of survey methods and field work similarly sought convergent validation by using different data collection methods. A limited form of triangulation based solely on the use of both quantitative and qualitative research approaches in a single study has become widely known as mixed methods research (see Mixed Methods Research). Yet it may be still more fruitful to mix within-methods or between-methods and to include not just two methods but multiple quantitative and/or qualitative methods employed in a single study instead.

Introductory Works

These works introduced the key ideas in triangulation and in mixed methods research, which stems from the logic of triangulation. Campbell and Fiske 1959 introduced the idea of triangulation in a paper addressing quantitative research. The authors argue that validity always requires multiple methods and multiple data sources. Webb, et al. 1966 applies Campbell and Fiske’s ideas to multiple methods of data collection, noting that oral claims could be challenged or validated via comparison and contrast with observations. Sieber 1973 is an early example of research using multiple data types. Denzin 1970 introduces a much more generally applicable, multidimensional conceptualization of triangulation; the author’s idea greatly expanded triangulation’s scope and possibilities. Jick 1979 applied and popularized the expanded vision of triangulation presented in Denzin 1970. Crano 1981 showed the value of triangulation in cross-cultural research, in which misunderstanding is common. Tashakkori and Teddlie 1998 focuses solely on one type of triangulation introduced by Denzin 1970 the combination of quantitative and qualitative methodologies. Tashakkori and Teddlie’s work is the foundation for mixed methods research widely used today. Creswell 1994, on qualitative and quantitative methods, offers a useful typology of mixed methods research designs. Creswell 2003 further elaborates on mixed methods typology in the second and renamed edition of this useful introductory text.

• Campbell, Donald, and D. Fiske. 1959. Convergent and discriminant validation by the multitrait-multimethod matrix. Psychological Bulletin 56.2 (March): 81–105.

  DOI: 10.1037/h0046016

  This classic paper introduced the concept of multiple operationalism into quantitative research. This concept points to the need for multiple methods and multiple-trait approaches to establish validity. Triangulation has its roots in this concept, though the concept is now applied to quantitative, qualitative, and mixed methods research.

• Crano, William D. 1981. Triangulation and cross-cultural research. In Scientific inquiry and the social sciences: A volume in honor of Donald T. Campbell. Edited by M. Brewer and Barry E. Collins, 317–344. San Francisco: Jossey-Bass.

  This chapter is a pioneering effort in applying triangulation in cross-cultural research. Crano argues that given the potentially large, and often tacit, differences among researchers and research participants, multiple methods will help identify areas of misunderstanding and different emphasis across cultures. Triangulation and mixed methods have become widely used methods in contemporary cross-cultural research.

• Creswell, John. 1994. Research design: Qualitative and quantitative approaches. Thousand Oaks, CA: SAGE.

  This book introduced mixed methods research designs to a wide social sciences and education audience. In it, Creswell briefly presents three mixed methods research designs, setting the stage for his later design typology.

• Creswell, John. 2003. Research design: Qualitative, quantitative, and mixed method approaches. 2d ed. Thousand Oaks, CA: SAGE.

  In this book, Creswell elaborates on his mixed method typology to include different weighing or emphasis on either quantitative or qualitative methods. He also offers a typology of the sequencing of use of each method.

• Denzin, Norman K. 1970. The research act: A theoretical introduction to sociological methods. Chicago: Aldine.

  This pioneering and classic work established the basis for multiple methods triangulation beyond its exclusive use in quantitative research, and made the case for combined qualitative-quantitative research. In addition, it offers the most widely used typology of triangulation in the social sciences. Denzin quite literally defined the territory of triangulation and mixed methods in this book.

• Jick, Todd D. 1979. Mixing qualitative and quantitative methods: Triangulation in action. Administrative Science Quarterly 24.4 (December): 602–611.

  DOI: 10.2307/2392366

  In this article, Jick seeks to offer some examples of the implementation of the concept of triangulation presented in Denzin 1970. With a “how-to” focus, Jick illustrates the use of triangulation in professional practice with administration and organizations. This early classic work is widely cited.

• Sieber, Sam D. 1973. The integration of fieldwork and survey methods. American Journal of Sociology 78.6 (May): 1335–1359.

  DOI: 10.1086/225467

  This pioneering article describes the combined use of fieldwork methods and structured surveys in sociology. Drawing on the logic of triangulation, it is among the first mixed methods works.

• Tashakkori, Abbas, and Charles Teddlie. 1998. Mixed methodology: Combining qualitative and quantitative approaches. Thousand Oaks, CA: SAGE.

  This monograph expanded the discussion of combining quantitative and qualitative research methods, known as mixed methods research, an offshoot of the broader territory of triangulation. Ironically, mixed methods research, which requires only two methods, may be a less powerful method than true triangulation, with its three or more data sources, methods, or analysis types.

• Webb, Eugene J., Donald T. Campbell, Richard D. Schwartz, and Lee Sechrest. 1966. Unobtrusive measures: Nonreactive research in the social sciences. Chicago: Rand McNally.

  Webb argued that uncertainty of interpretation decreases when a proposition is supported by two or more independent measurement processes. More broadly, this book points to different types of data that may be triangulated usefully. Unobtrusive measures should document actions and experiences in context with little possibility of reactivity. Combining intrusive and unobtrusive measures allows comparison of words versus deeds.