Internal Validity
Internal validity establishes the accuracy with which information is captured and interpreted (Ritchie and Lewis 2003). This type of validation applies to the explanatory portion of case studies, where a causal relationship is being established (Yin 1994). This study employed affinity diagramming to organize the data and search for patterns. An affinity diagram is a technique for “organizing vast amounts of qualitative data to identify any natural patterns or groupings to allow a better understanding of a problem” (White et al. 2002). The determinants of evolution and sensitivity were developed through affinity diagraming by grouping similar interview responses and then creating a group name that was representative of the responses in that group.