Table 1. The Four PBRN Studies Included in this Study

Study Name	Practices (n)	Study Design	Study Duration (months)	Central Sites	Status	Funding	Practice Change	Discontinued Practices (n)
Introduction of Spirometry into Primary Care	18	Before/after observational	18	OMC and AAFP NRN Care Net	Completed in 2006²⁰	NHLBI	Using spirometry to evaluate patients with asthma and COPD	1 (unable to enroll patients)
TRIPPD (Translating Research into Primary Care Practice for Postpartum Depression)	28	Randomized controlled trial	60	OMC and AAFP NRN	Completed in 2010^21,22	AHRQ	Introducing screening, diagnosis, and management support for postpartum depression	4 (2 practices dissolved, 1 practice had long-term illness of local primary investigator, 1 practice could not meet enrollment goals)
The Asthma Tools Study	28	Randomized controlled trial	60	OMC and AAFP NRN	In progress	AHRQ	Using new asthma tools in managing children and adults with asthma	1 (Practice destroyed by tornado, unable to continue while trying to rebuild)
BELT (Black Asthmatic's Exacerbations with LABA vs Tiotropium)	30	Randomized controlled trial	36	OMC, AAFP NRN, and Harvard Medical School	In progress²³	AHRQ	Assessing the impact on exacerbation rates of 2 classes of long-acting bronchodilators in black adults with asthma	3 (1 practice unable to do work, 2 sites unable to meet enrollment goals)

AAFP NRN, American Academy of Family Physicians National Research Network; AHRQ, Agency for Healthcare Research and Quality; NHLBI, National Heart, Lung and Blood Institute; OMC, Olmsted Medical Center.