and they appear to go up when personal belief exemptions go away, which might be caused by a replacement effect, researchers hypothesized in .
“Put differently, state-level religious exemption rates appear to be a function of personal belief exemption availability, decreasing significantly when states offer a personal belief exemption alternative,” the researchers explained.
Led by Joshua T.B. Williams, MD, of the department of pediatrics at the Denver Health Medical Center, the researchers sought to update state-level analyses of vaccination exemption rates by performing a cross-sectional, retrospective investigation of publicly available aggregated yearly vaccine reports for kindergartners from the Centers for Disease Control and Prevention. They were specifically interested in the school years of 2011-2012 through 2017-2018 “to extend and provide meaningful comparisons to a previous study of exemption data” that had ended its study period in 2015-2016 (Open Forum Infect Dis. 2017 Nov 15.). The researchers adjusted for heterogeneous exemption processes by coding for “difficulty” of obtaining such exemptions in accordance with that previous study’s methods because studies have suggested that nonmedical exemption rates are lower in states with more difficult exemption policies. They also looked at how rates of religious exemptions changed in Vermont after the state eliminated personal, or philosophical, exemptions in 2016. The final analysis included 295 state-years from among the 45 states and the District of Columbia that all allow religious exemptions and the 15 states that permit personal belief exemptions.
The unadjusted analysis showed that the mean proportion of kindergartners with religious exemptions was lower where personal belief exemptions were available (0.41%; 95% confidence interval, 0.28%-0.53%) than they were where only religious exemptions were an option (1.63%; 95% CI, 1.30%-1.97%). In the adjusted analysis, states with both religious and personal belief exemptions were only a quarter as likely to have kindergartners with religious exemptions than those without personal belief exemptions (adjusted risk ratio, 0.25; 95% CI, 0.16-0.38). Furthermore, the proportion of kindergartners in Vermont with religious exemptions went from 0.5% in the years 2011-2012 through 2015-2016 when personal belief exemptions were still an option, to 3.7% in 2016-2017 through 2017-2018, after they went away.
One of the study’s limitations is that not all states used the same methods of data collection; however, the authors felt that, given about three-quarters of states included performed censuses with at least 80% of children counted, the effects on the study’s results should be minimal.
After discussing the role of religious exemptions and some of their history, as well as citing the seemingly paradoxical reported decline in religiosity and rise in religious exemptions, the researchers wrote in their conclusion that these “may be an increasingly problematic or outdated exemption category, and researchers and policy makers must work together to determine how best to balance a respect for religious liberty and the need to protect public health.”
SOURCE: Williams JTB et al. Pediatrics. 2019 Nov. .