Generalisability, Usability, Linguistics (and cultural Location) and Psychometrics. Our acronym to organise thinking about outcome/change measures.
Chapter 2 is all about GULP so borrow or buy a copy of the book!!
More seriously, GULP is probably one of the more important ideas in the book as it relegates psychometrics behind Generalisability, Usability, Linguistics (and cultural Location) underlining that in the field of change measurement, certainly for MH/WB and interventions generally, conventional psychometric analyses are less important than GUL.
Try also … #
Language and culture