“…Demonstrations have rarely utilized randomized designs, and most have either lacked comparison sites, 17 been implemented in older, sicker or specialized populations, 18 had comparisons of convenience, 5 or lacked revised payment arrangements, 19 thought to be essential to the transition. 2 While the number of practices recognized as PCMH by the National Committee for Quality Assurance (NCQA) is growing daily, 14,20 it is challenging for practices to change the wide range of practice components 8,[21][22][23][24] required by the multidimensional PCMH model. These reports include little detail on change along the PCMH dimensions 17 of enhanced access to a physician led team, continuity and coordination of comprehensive care, promotion of patient self-management, and use of evidence-based medicine facilitated by registries, health information technology and exchange.…”