OBJECTIVES To compare two consensus development methods commonly used for developing clinical guidelines in terms of the judgments produced, closeness of consensus, amount of change between rounds, concordance with research evidence and reliability. METHODS In all, 213 general practitioners and mental health professionals from England participated in four Delphi and four nominal groups. They ...

We present a generalisation of first-order unification to the practically important case of equations between terms involving binding operations. A substitution of terms for variables solves such an equation if it makes the equated terms α-equivalent, i.e. equal up to renaming bound names. For the applications we have in mind, we must consider the simple, textual form of substitution in which n...

We investigate different notions of nominal words, that is, words that my contain letters from an alphabet as well as names and name-binders. In a first section we construct them from first principles. In a second section we take the point of view that—as in the classical case—words over an alphabet S form a free monoid over S. We define different notions of nominal monoids and reveal nominal w...