Limitations of the Utility of Categorization in eDiscovery Review Efforts

In large-scale litigation, an eDiscovery production request typically consists of numerous individual Requests for Production (“RFPs”), each specifying a category of information sought. In this study, we investigate the effects on assessor performance—measured in terms of review speed and consistency in categorization—when using 55 individual RFPs versus a lesser number of broader composite categories (“CCs”) covering the same underlying RFPs, applied to the same document population. Our results show that increasing the number of review categories has a substantial and significant negative impact on both review speed and the consistency in categorization achieved by assessors. The overall inability of assessors to achieve consistent categorizations raises serious questions about the utility of the practice of categorization in eDiscovery review efforts.