Research Associate Professor, College of Health and Human Development
Principal Investigator, The Methodology Center
The Methodology Center
The Pennsylvania State University
400 Calder Square II
State College, PA 16801
Ph.D., University of North Carolina, 2005 (Quantitative Psychology)
M.A., James Madison University, 2001 (Psychological Sciences)
B.S., James Madison University, 1999 (Psychology)
Current Projects and Collaborators
I collaborate with Debashis Ghosh on extending statistical learning/data mining methods to estimate propensity scores in the mediation context and to estimate propensity scores for continuous exposure variables. Debashis and I also collaborate on a project using the least absolute shrinkage and selection operator (LASSO) for variable selection in propensity score modeling. I collaborate with Stephanie Lanza, Bethany Bray, and Megan Schuler on a project to extend causal inference methods to latent variable exposures and outcomes. Finally, I collaborate with Angela Henneberger on using propensity score models to model peer influence and selection effects in social networks.
My research is primarily in the area of statistical methodology, especially in the integration of statistical methodology and prevention science. My specific methodological interests are in developing methods for strengthening causal inferences from observational data and in mediation analysis, including innovative applications of these methods. More recently, I have begun to focus on advancing and applying statistical learning methods for intensive longitudinal data to address complex research questions in the behavioral health sciences.
Selected Grants and Awards
Center for Prevention and Treatment Methodology (The Methodology Center)
National Institute on Drug Abuse: P50DA010075
1/1/08 - present; Role: Co-Investigator (PI: Linda Collins)
HealthWise Dissemination: Translation to Multiple Schools
National Institute on Drug Abuse: R01 DA029084
12/1/2010-present; Role: Co-Investigator (PI: Linda Caldwell)
Mexican Children of Immigrants Program
National Institute of Child Health and Human Development: 1P01HD62498-01A1
4/1/11-present; Role- Co-Investigator (PI: Nancy Landale)
Geisinger Rural Aging Study
U.S. Department of Agriculture: 1950-51530-010-OOD
7/3/2009-present; Role: Co-Investigator (Subcontract PI: Gordon Jensen)
Marginal Causal Models for Observational Studies in Obesity Research
National Institute of Diabetes and Digestive and Kidney Diseases: R21DK082858
7/1/09 - 6/30/12; Role: Co-Investigator (7/30/09-6/30/11 PI: Joseph Schafer); PI (7/1/11-6/30/2012)
Selected Courses Taught
Causal Inference in the Behavioral Sciences I/II (Graduate)
Causal Inference in the Social Sciences (Graduate)
Mediation Analysis in the Social Sciences (Graduate)
Psychological Statistics (Undergraduate)
Selected Peer-Reviewed Articles
Crowley, D. M., Jones, D. E., Coffman, D., & Greenberg, M. (in press). Can we build an efficient response to the prescription drug abuse epidemic? Assessing the cost effectiveness of universal prevention. Preventive Medicine.
Butera, N. M., Lanza, S. T., & Coffman, D. L. (2013). A framework for estimating causal effects in latent class analysis: Is there a causal link between early sex and subsequent profiles of delinquency? Prevention Science. doi: 10.1007/s11121-013-0417-3 PMCID: PMC3888479
Crowley, D. M., Coffman, D. L., Feinberg, & Greenberg, M. (2013). Evaluating the impact of implementation factors on family-based prevention programming: Methods for strengthening causal inference. Prevention Science. Advance online publication. doi: 1001007/s11121-012-0352-8 NIHMSID: NIHMS505286
Lanza, S. T., Coffman, D. L., & Xu, S. (2013). Causal inference in latent class analysis. Structural Equation Modeling, 20(3), 361-383. PMC Journal-In Process
Lippold, M., Coffman, D., & Greenberg, M. (2013). Investigating the potential causal relationship between parental knowledge and youth risky behavior: A propensity score analysis. Prevention Science. Advance online publication. doi: 10.1007/s11121-013-0443-1
Solmeyer, A. R., Feinberg, M. E., Coffman, D. L., & Jones, D. E. (2013). The effects of the Family Foundations prevention program on coparenting and child adjustment: A mediation analysis. Prevention Science. Advance online publication. doi: 10.1007/s11121-013-0366-x PMCID: PMC3683104
Coffman, D. L., Caldwell, L. L., & Smith, E. A. (2012). Introducing the at-risk average causal effect with application to HealthWise South Africa. Prevention Science. Advance online publication. doi:10.1007/s11121-011-0271-0 PMCID: PMC3405190
Coffman, D. L., & Kugler, K. C. (2012). Causal mediation of a human immunodeficiency virus preventive intervention. Nursing Research, 61(3), 224-230. PMCID: PMC3377683
Coffman, D. L., & Zhong, W. (2012). Assessing mediation using marginal structural models in the presence of confounding and moderation. Psychological Methods, 17,(4), 342-664. doi: 10.1037/a0029311 PMCID: PMC3553264
Coffman, D. L. (2011). Estimating causal effects in mediation analysis using propensity scores. Structural Equation Modeling, 18(3), 357-369. PMCID: PMC3212948
Coffman, D. L., Smith, E. A., Flisher, A. J., & Caldwell, L. L. (2011). Effects of HealthWise South Africa on condom use self-efficacy. Prevention Science, 12(2), 162-172. PMCID: PMC3102775
Maydeu-Olivares, A., Coffman, D. L., Garcia-Forero, C., & Gallardo-Pujol, D. (2010). Hypothesis testing for coefficient alpha: An SEM approach. Behavior Research Methods, 42(2), 618-625. PMCID: PMC3027072
Coffman, D. L., & Belue, R. (2009). Disparities in sense of community: True race differences or differential item functioning? Journal of Community Psychology, 37(5), 547-558. PMCID: PMC2772185
Maydeu-Olivares, A., Kramp, U., Garcia-Forero, C., Gallardo-Pujol, D., & Coffman, D. (2009). The effect of varying the number of response alternatives in rating scales: Experimental evidence from intra-individual effects. Behavior Research Methods, 41(2), 295-308.
Coffman, D. L. (2008). Model misspecification in covariance structure models: Some implications for power and Type I error. Methodology, 4(4), 159-167.
Coffman, D. L., Maydeu-Olivares, A., & Arnau, J. (2008). Asymptotically distribution-free interval estimation for an intraclass correlation coefficient with applications to longitudinal data. Methodology, 4(1), 4-9.
Coffman, D. L., Patrick, M. E., Palen, L., Rhoades, B. L., & Ventura, A. K. (2007). Why do high school seniors drink? Implications for a targeted approach to intervention. Prevention Science, 8, 241-248.
Maydeu-Olivares, A., Coffman, D. L., & Hartmann, W. M. (2007). Asymptotically distribution-free interval estimation for coefficient alpha. Psychological Methods, 12(2), 157-176.
Maydeu-Olivares, A., & Coffman, D. L. (2006). Random intercept item factor analysis. Psychological Methods, 11(4), 344-362.
Coffman, D. L., & Millsap, R. E. (2006). Evaluating latent growth curve models using individual fit statistics. Structural Equation Modeling, 13(1), 1-27.
Selected Book Chapters
Coffman, D. L. (in press). Third variables: Scientific meanings and modeling in non-randomized studies. In S. J. Henley (Ed.), Advanced Quantitative Methods in Nursing Research. London, UK: Routledge International.
Coffman, D. L. (2013, November). Assessing causal mediation of the RRR intervention on sexual risk behavior among recently released female prisoners. Paper presented at the National Institute on Drug Abuse Prevention Research Branch Seminar, Bethesda, MD.
Coffman, D. L. (2013, October). Big Data: Opportunities and Challenges. Presented at the National Cancer Institute Science of Research and Technology Branch Big D.A.T.A. (Data And Theory Advancement) Workshop, National Institutes of Health, Bethesda, MD.
Coffman, D. L. (2013, October). Comparison of potential outcome approaches for assessing causal mediation. Presented at the Prevention Science and Methodology Group.
Coffman, D. L. (2013, October). Methodology workshop: Propensity score methods for estimating causality in the absence of random assignment: Applications for child care policy research. Presented at the Annual Meeting of the Child Care Policy Research Consortium. Bethesda, MD
Bray, B. C., Lanza, S. T., & Coffman, D. L. (2013, September). The causal effect of substance use latent class membership on a distal outcome. Paper presented at the Paper presented at the 10th International Conference on Health Policy Statistics, Chicago, IL.
Zhu, Y., Coffman, D. L., & Ghosh, D. (2013, August). A data-adaptive approach to modeling propensity scores for continuous treatments. Paper presented at the Joint Statistical Meetings, Montreal, Canada.
Lanza, S. T., Bray, B. C., Coffman, D. L. (2013, May). The causal effect of substance use latent class membership on a distal outcome. Paper presented at the Society for Prevention Research 21st annual meeting, San Francisco, CA.
Coffman, D. L., Bray, B. C., Lanza, S. T., & Dziak, J. J. (2013, May). Estimating the causal effect of a latent class treatment on binary and count outcomes. Paper presented at the Society for Prevention Research 21st annual meeting, San Francisco, CA.
Zhu, Y., Ghosh, D., & Coffman, D. L. (2013, Mar.). Improving mediation analysis based on propensity scores. Presented at the Eastern North American Region of the International Biometric Society, Orlando, FL.
Coffman, D. L., MacKinnon, D. P., Zhu, Y., & Ghosh, D. (2013, Jan.). Comparison of three approaches to causal mediation analysis. Presented at the Causal Mediation Analysis Symposium, Ghent, Belgium.
Coffman, D. L. (2012, October). Methodology workshop: Propensity score methods for estimating causality in the absence of random assignment: Applications for child care policy research. Presented at the Annual Meeting of the Child Care Policy Research Consortium, Bethesda, MD.
Zhu, Y., Ghosh, D., & Coffman, D. (2012, August). Mediation analysis based on propensity scores. Presented at the Joint Statistical Meetings, San Diego, CA.
Selected Software & Technical Reports
Ghosh, D., Zhu, Y., & Coffman, D. L. (2013). Penalized regression procedures for variable selection in the potential outcomes framework. Technical Report. University Park, PA: Penn State University, Department of Statistics. Available at: http://works.bepress.com/debashis_ghosh/59
Schoemann, A. M., Preacher, K. J., & Coffman, D. L. (2010, April). Plotting power curves for RMSEA. [Software]. Lawrence, KS: University of Kansas. Available at http://www.quantpsy.org.
Preacher, K. L., & Coffman, D. L. (2006). Computing power and minimum sample size for RMSEA. [Software]. Laurence, KS: University of Kansas. Available at http://www.quantpsy.org.