under review

Hassmiller Lich, K., O’Leary, M., Nambiar, S., Townsley, R., Mayorga, M., Hicklin, K., Frerichs, L., Shafer, P., Davis, M. & Wheeler, S. Estimating the impact of insurance expansion on colorectal cancer and related costs in North Carolina: a population-level simulation analysis. Revise and resubmit, Preventive Medicine.

Shafer, P., Dusetzina, S., Sabik, L., Platts-Mills, T., Stearns, S., & Trogdon, J. Insurance instability and use of emergency and office-based care after gaining coverage: an observational study.

Shafer, P., Anderson, D., Aquino, S., Baum, L., Fowler, E., & Gollust, S. Insurance advertising under political uncertainty: relationship between advertising and Marketplace enrollment.



Ngo-Metzger, Q., Zuvekas, S., Shafer, P., Tracer, H., Borsky, H., & Bierman, A. Statin use in the U.S. for secondary prevention of cardiovascular disease remains suboptimal. Journal of the American Board of Family Medicine, forthcoming.

Anderson, D. & Shafer, P. The Trump effect: post-inauguration changes in Marketplace enrollment. Journal of Health Policy, Politics, and Law.

Shafer, J., Shafer, P., & Haley, K. Caregivers navigating rehabilitative care for people with aphasia after stroke: a multi-lens perspective. International Journal of Language and Communication Disorders.

Gertner, A., Rotter, J., & Shafer, P. Association between state minimum wages and suicide rates in the US. American Journal of Preventive Medicine.

Shafer, P. Impact of U.S. smoke-free air laws on restaurant and bar employment, 1990–2015. Nicotine and Tobacco Research.

Shafer, P., Borsky, A., Ngo-Metzger, Q., Miller, T., & Meyers, D. The practice gap: national estimates of screening and counseling for alcohol, tobacco, and obesity. Annals of Family Medicine.

Davis, M., Shafer, P., Renfro, S., Hassmiller Lich, K., Shannon, J., McConnell, J., & Wheeler, S. Does a transition to accountable care in Medicaid shift the modality of colorectal cancer testing? BMC Health Services Research.


Shafer, P., Fowler, E., Baum, L., & Gollust, S. Television advertising and Marketplace consumer engagement: a natural experiment in Kentucky. Journal of Medical Internet Research.

Trogdon, J., Shafer, P., Lindsay, B., & Coyne-Beasley, T. Impact of introduction of the 9-valent human papillomavirus vaccine on vaccination coverage of youth in North Carolina. Vaccine.

Trogdon, J., Shafer, P., Lindsay, B., & Coyne-Beasley, T. Determinants of the receipt of the 9-valent human papillomavirus vaccine in the first year after introduction in North Carolina. Vaccine.

Davis, K., Patel, D., Shafer, P., Duke, J., Glover-Kudon, R., Ridgeway, W., & Cox, S. Association between variation in media doses of the Tips From Former Smokers campaign and cessation behaviors and intentions among cigarette smokers, 2012–2015. Health Education and Behavior.


Shafer, P. Impact of U.S. smoke-free air laws on restaurants and bars by employer size: a panel study. BMJ Open.

Agaku, I., Davis, K., Patel, D., Shafer, P., Cox, S., Ridgeway, W., & King, B. A longitudinal study of the relationship between receptivity to e-cigarette advertisements and e-cigarette use among baseline non-users of cigarettes and e-cigarettes, United States. Tobacco Induced Diseases.

Farrelly, M. & Shafer, P. Comparing trends between food insecurity and cigarette smoking among adults in the United States, 1998–2011. American Journal of Health Promotion.

Kim, A., Nonnemaker, J., Guillory, J., Shafer, P., Parvanta, S., Holloway, J., & Farrelly, M. Antismoking ads at the point of sale: the influence of ad type and context on ad reactions. Journal of Health Communication.

Davis, K., Duke, J., Shafer, P., Patel, D., Rodes, R., & Beistle, D. Perceived effectiveness of antismoking ads and association with quit attempts among smokers: evidence from the Tips From Former Smokers campaign. Health Communication.

Caraballo, R., Shafer, P., Patel, D., Davis, K., & McAfee, T. Quit attempt methods used by U.S. adult cigarette smokers. Preventing Chronic Disease.

McAfee, T., Davis, K., Shafer, P., Patel, D., Alexander, R., Jr., & Bunnell, R. Increasing the dose of television advertising in a national anti-smoking media campaign: results from a randomized field trial. Tobacco Control.


Davis, K., Shafer, P., Rodes, R., Kim, A., Hansen, H., Patel, D., Coln, C., & Beistle, D. Does digital video advertising increase population-level reach of multimedia campaigns? Evidence from the 2013 Tips From Former Smokers campaign. Journal of Medical Internet Research.

Patel, D., Davis, K., Cox, S., Bradfield, B., King, B., Shafer, P., Caraballo, R., & Bunnell, R. Reasons for current e-cigarette use among U.S. adults. Preventive Medicine.

Trogdon, J., Shafer, P., Shah, P., & Calo, W. Are state laws granting pharmacists authority to vaccinate associated with HPV vaccination rates among adolescents? Vaccine.

Neff, L., Patel, D., Davis, K., Ridgeway, W., Shafer, P., & Cox, S. Evaluation of the national Tips From Former Smokers campaign: the 2014 longitudinal cohort. Preventing Chronic Disease.

Shafer, P. & Loomis, B. Economic impact of smoke-free air laws in North Dakota on restaurants and bars. Nicotine and Tobacco Research.

Shafer, P., Davis, K., Patel, D., Rodes, R., & Beistle, D. Association between media dose, ad tagging, and changes in web traffic for a national tobacco education campaign: a market-level longitudinal study. Journal of Medical Internet Research.

Nonnemaker, J., Kim, A., Shafer, P., Loomis, B., Hill, E., Holloway, J., & Farrelly, M. Influence of point-of-sale tobacco displays and plain black and white cigarette packaging and advertisements on adults: evidence from a virtual store experimental study. Addictive Behaviors.

Davis, K., Allen, J., Duke, J., Nonnemaker, J., Bradfield, B., Farrelly, M., Shafer, P., & Novak, S. Correlates of marijuana drugged driving and openness to driving while high: evidence from Colorado and Washington. PLoS ONE.

Lee, Y., Shafer, P., Eggers, M., Kim, A., Parvanta, S., & Nonnemaker, J. Effect of a voluntary e-cigarette warning label on risk perceptions. Tobacco Regulatory Science.


Davis, K., Alexander, R., Jr., Shafer, P., Mann, N., Malarcher, A., & Zhang, L. The dose-response relationship between tobacco education advertising and calls to quitlines in the United States. Preventing Chronic Disease.

Kim, A., Lee, Y., Shafer, P., Nonnemaker, J., & Makarenko, O. Adult smokers’ receptivity to a television advert for electronic nicotine delivery systems. Tobacco Control.


Kim, A., Nonnemaker, J., Loomis, B., Shafer, P., Shaikh, A., Hill, E., Holloway, J., & Farrelly, M. Influence of point-of-sale tobacco displays and graphic health warning signs on adults: evidence from a virtual store experimental study. American Journal of Public Health.


Loomis, B., Shafer, P., & van Hasselt, M. The economic impact of smoke-free laws on restaurants and bars in 9 states. Preventing Chronic Disease.

Kim, A., Nonnemaker, J., Loomis, B., Baig, A., Hill, E., Holloway, J., Farrelly, M., & Shafer, P. Influence of tobacco displays and ads on youth: a virtual store experiment. Pediatrics.