Results: Process improvement Abstract Background Care for infants with a hypoplastic left heart syndrome (HLHS, “half a heart”) is complex and early mortality is high. Only about 350 infants/year in the US survive the initial surgery that occurs shortly after birth. An additional 10-15% die in the ‘interstage’ period before a second required open-heart surgery at 4-6 months of age. The National Pediatric Cardiology Quality Improvement Collaborative (NPC-QIC) is focused on improving outcomes, including interstage survival, for these infants Methods Data entered to the NPC-QIC registry between 7/ /2014 were analyzed. The primary outcome was aggregate interstage mortality. Centers join NPC-QIC on a rolling basis. Clinical teams collaborated on clinical practice changes addressing: 1) care coordination; 2) care transitions; 3) interstage growth; and 4) engaging families. Mortality was monitored using a cumulative mortality chart but required additional statistical process control charts to demonstrate improvement. Center adherence to clinical processes expected to affect mortality was also tracked. Results Data were included from 52 surgical sites and 1,163 infants completing the interstage (1,050 underwent stage 2 palliation, 18 underwent interstage transplantation, 96 experienced interstage mortality).. Performance on key process measures improved. Cumulative aggregate mortality between 2008 and the end of 2012 was 9.8%, lower than published previously. Between January 2013– July 2014, cumulative aggregate mortality was reduced to 5.9%, a relative reduction of 39.7%. Conclusions increased reliability in key care processes at participating centers has contributed to this reduction in mortality as we are not aware of any new medications or other therapies during our study period. A learning health network, as exemplified by NPC-QIC, can achieve important improvements in patient outcome even with rare pediatric conditions. Methods: Key Driver Diagram Results: Collaborative growth and patient demographics Conclusions Outcome improvement in a rare disease population througha national pediatric learning network Jeffrey B. Anderson MD MBA, Robert H. Beekman III MD, John D. Kugler MD, Geoffrey L. Rosenthal MD PhD, Kathy J. Jenkins MD, Thomas S. Klitzner MD PhD, Gerard R. Martin MD, Steven R. Neish MD, David Brown MD, Colleen Mangeot MS, Eileen King PhD, Laura E. Peterson BSN SM, Lloyd Provost MS, Carole Lannon MD MPH For the National Pediatric Cardiology Quality Improvement Collaborative This is the first report of reduction in interstage mortality in a large collection of infants with HLHS. Cumulative aggregate mortality improved from 9.8% to 5.9%, a relative reduction of 39.7%. Improvements can be identified in rare populations by applying statistical process control methods. These methods allow identification of statistically significant changes over time in relatively small patient population. Cooperation among centers, exemplified by the NPC-QIC learning networks model, is essential in improving clinical care in fields care for patients with rare disorders. Aim The purpose of this study was to describe the improvement in interstage mortality achieved since the formation of NPC-QIC. We also sought to describe the statistical techniques used to identify these changes in a rare disorder such as HLHS. Methods The NPC-QIC registry captures information about infants with hypoplastic left heart syndrome (“half a heart’) who undergo an initial surgery during the newborn period with plans for subsequent additional surgical palliation. Data is collected at individual surgical centers an entered locally into a RedCap database then analyzed centrally by the NPC-QIC data team. Our primary outcome is interstage mortality. In measuring and reporting interstage mortality a number of statistical process control (SPC) methods and charts are employed. We track adherence to several process measures felt to likely be associated with improvement in interstage mortality. Process and outcome data are reported to individual centers on a monthly basis. Results: cumulative mortality Results: Changes in mortality Mortality G-chart The cumulative mortality chart has been fairly stable and demonstrated a collaborative-wide mortality of 9.8% between 2008 and the end of The mortality G-chart demonstrates special cause in April 2013 and a change in geometric pattern starting in early The supplemental p-chart and Cusum chart confirm the changes suspected In the G-chart and demonstrate a reduction in mortality of 39.7%. There has been significant improvement in several process measures felt to be contributors to interstage mortality.