Scientific Validity of the GLP
The GLP is based on Torbert’s 30+ years of research (see, in Resources Torbert & Associates, Action Inquiry: The Secret of Timely and Transforming Leadership [Berrett-Koehler, 2004], as well as Seven Transformations of Leadership [April 2005 Harvard Business Review].The 2013 scholarly summary CDAI appears in Torbert’s Listening into the Dark: (Integral Review April 2013) And for the latest methodological review of five different measures (2014), see Bill’s Developmental Measures Compared
Torbert has been involved in testing the validity of several developmental leadership measures that are close equivalents, and the GLP is the latest version, building on the validity of the others, while improving upon them in various ways. (See Torbert articles and book chapters at end of page.) For example, we now offer each person who takes the GLP a Self-Estimate document that supports making your own subjective estimate of your centre-of-gravity action-logic before receiving our relatively objective estimate. This process generates better conversation afterwards both within yourself and with a coach.
Also, we no longer depend merely on occasional testing of reliability between scorers. Instead, each set of sentence completions submitted is tested for reliability between two of the half dozen most senior scorers of such developmental instruments.
Finally, even more important than the already-established validity of the objective GLP instrument is the catalytic validity that engaging the action inquiry process at a workshop or with an executive coach achieves on behalf of your ongoing transformation to later leadership action-logics.