Combination and Triangulation of Methods and Data

Gyde Hansen, December 29, 2005



In empirical TS, combining methods and data has become an important research technique. This procedure is often called “triangulation”. For example, data from first-person observations (TAPs) are combined with data from third-person observations (the observer) in order to reach inter-subjectivity. Qualitative approaches are corroborated or complemented by quantitative approaches. This latter combination is often looked upon as especially useful, because quantitative data, which are a result of measuring and counting, are regarded as more objective and reliable than qualitative data, which are a result of persons’ perceptions and more subjective interpretations of a phenomenon (see Hansen, this website: February 17, 2005). 


Triangulation is frequently applied in social sciences and in many other disciplines, and the terms combination and triangulation are often used as synonyms for a mix of procedures to grasp complex phenomena and to confirm or complete a study. Triangulation is regarded as a multimix of material, strategies, methods, purposes, perspectives or investigators in an attempt to add rigor to a study.


The use of the triangulation metaphor has been heavily discussed and challenged, and much has been written about triangulation as a useful approach, especially in qualitative research. In its original meaning the term ‘triangulation’ refers to a geometrical procedure where a point is found by calculating the length of one side of a triangle, given measurements of angles and sides of the triangle formed by that point and two other given reference points. This means that in triangulation as opposed to any other combination of methods or data, reference points, i.e. prior knowledge, are used in order to gain further results or further insight.


Having the meaning of the original metaphor of a triangle in mind, combination and triangulation could be kept apart. Combination is useful for all kinds of information collection involving multiple methods, investigators, tools, observations and data. Triangulation, in accordance with the original meaning of the term, can be an additional procedure for obtaining new results or new knowledge from existing results, and can thus provide clarity and coherence to the investigation and description of complex phenomena. In complex research projects, where many aspects have to be taken into consideration, the differentiation between combination and triangulation is a means to keep the variety of different observations under control and to make it easier to discuss, repeat and reevaluate the study. For example, data from interviews or questionnaires about the personal background of subjects can be combined with product data (evaluation of target texts), or the same data can be combined with process data from introspection. Triangulated, the results of both combinations can complete each other or reveal gaps or discrepancies and thus provide new knowledge about the relationship between personal profiles, processes and products. A complex study gains flexibility and scope when new results can be located via new constructions of triangles from known reference points (= results).