The Delphi method ensured early contributions were made without
the influence of other group members
The three rounds of Delphi method were critical to the development of
the final list. In particular, the comments from the experts in Round
Two and associated workshops were invaluable in dealing with the
challenge of choosing a single core concept from a cluster of related
terms. For example, numerous expert comments were received regarding the
related terms margin of safety, therapeutic window, andtherapeutic index. These comments informed the final decision to
propose therapeutic index in Round Three and subsequent 90%
endorsement of this concept. This is consistent with earlier findings
supporting the use of three rounds of expert analysis (Hallowell &
Gambatese, 2010). An innovative part of our Delphi method was the use of
workshops between Rounds Two and Three, with workshop discussions useful
in shaping the clustering of terms around a central concept. The
workshops also permitted discussion and input from a wider team outside
of the core research team. That said, the workshops may have affected
the independent nature of the expert ratings on the final Delphi round,
so only the expert group ratings in the first two rounds were truly
independent.