Here are a couple of theses/dissertations on the subject:
- A survey of the development of sight-reading skills in instructional piano methods for average-age beginners and a sample primer-level sight-reading curriculum
Scott Dirkse M.M., University of South Carolina, 2009(h/t Veelo on PianoWorld.com) - A Theoretical Model of Piano Sightplaying Components
Dneya Bunnag Udtaisuk, Ph.D. University of Missouri-Columbia, 2005
- Performance without Preparation: Structure and Acquisition of Expert Sight-Reading and Accompanying Performance
Andreas C. Lehmann & K. Anders Ericsson, Florida State University - Sight-reading Ability of Expert Pianists in the Context of Piano Accompanying. (p 186)A.C.Lehmann & K.A. Ericsson
- Sight-reading (Chapter 32 of The Oxford handbook of music psychology (2009))Andreas C. Lehmann and Reinhard Kopiez