Improving Timeliness of Sweat Test for Cystic Fibrosis in All Infants with Out-of-range Screen

Early diagnosis of cystic fibrosis (CF) leads to better outcomes. CF newborn screening occurs in the United States, and the ultimate diagnosis requires referral for sweat chloride testing (SCT), ideally within 28 days of life. At our center, 60% of CF newborn SCTs occurred outside the recommended window. Recognizing known differences in CF detection by newborn screen across race and ethnicity groups, we also identified a gap in understanding of potential inequities in SCT timeliness in our center.

We used the Model for Improvement to understand key drivers for late SCT, focusing on optimizing internal processes and partnership with primary care providers and patient families. We implemented iterative Plan-Do-Study-Act cycles to effect change. Additionally, we developed a tracking tool to evaluate timeliness by self-reported race, ethnicity, and primary language.

We improved the rate of timely SCT from 40% to greater than 80% within the first project year, which was sustained over the subsequent year. We identified disparities in SCT timeliness by demographic characteristics, with those identified as Hispanic, Black, and multiracial having lower rates of timely SCT compared with those identified as White. There was a trend toward a lower rate of timely SCT in those speaking a non-English language as their primary language.

This work provided a framework for CF center-based improvement of the SCT process after an out-of-range CF screen, recognizing the importance of partnership with referring providers and understanding the patient voice. After uncovering disparities within our CF center, further work is needed to understand the drivers of these inequities and to develop and study solutions.