Faculty Affiliates

A. James O'Malley, PhD

Professor of Biostatistics, Department of Biomedical Data Science, The Dartmouth Institute for Health Policy and Clinical Practice

Bayesian Methods; Social Network Analysis; Causal Inference; Multivariate-Multilevel Models


A. James O'Malley, PhD
Professor of Biostatistics, Department of Biomedical Data Science, The Dartmouth Institute for Health Policy and Clinical Practice

Selected Publications
  • O'Malley AJ, Park S. A novel cluster sampling design that couples multiple surveys to support multiple inferential objectives. Health Serv Outcomes Res Methodol. 2020 Sep;20(2-3):85-110. doi: 10.1007/s10742-020-00210-y. PMID: 33613088; PMCID: PMC7888270.
  • Levy JJ, O'Malley AJ. Don't dismiss logistic regression: The case for sensible extraction of interactions in the era of machine learning. BMC Med Res Methodol. 2020 Jun 29;20(1):171. doi: 10.1186/s12874-020-01046-3. PMID: 32600277; PMCID: PMC7325087.
  • O'Malley AJ, Moen EL, Bynum JPW, Austin AM, Skinner JS. Modeling peer effect modification by network strength: The diffusion of implantable cardioverter defibrillators in the US hospital network. Stat Med. 2020 Apr 15;39(8):1125-1144. doi: 10.1002/sim.8466. PMID: 31925971.
  • Moen EL, Bynum JP, Skinner JS, O'Malley AJ. Physician network position and patient outcomes following implantable cardioverter defibrillator therapy. Health Serv Res. 2019 Aug;54(4):880-889. doi: 10.1111/1475-6773.13151. PMID: 30937894; PMCID: PMC6606612.
  • Ramkumar N, Martinez-Camblor P, Columbo JA, Osborne NH, Goodney PP, O'Malley AJ. Adverse events after atherectomy: Analyzing long-term outcomes of endovascular lower extremity revascularization techniques. J Am Heart Assoc. 2019 Jun 18;8(12):e012081. doi: 10.1161/JAHA.119.012081. PMID: 31165658; PMCID: PMC6645635.
  • An C, O'Malley AJ, Rockmore DN. Towards intelligent complex networks: the space and prediction of information walks. Appl Netw Sci. 2019;4(1):35. doi: 10.1007/s41109-019-0140-5. PMID: 31259230; PMCID: PMC6565809.
  • Huling JD, Yu M, O'Malley AJ. Instrumental variable based estimation under the semiparametric accelerated failure time model. Biometrics. 2019 Jun;75(2):516-527. doi: 10.1111/biom.12985. PMID: 30357822.
  • O'Malley AJ, James P, MacKenzie TA, Byun J, Subramanian SV, Block JP. Modeling a bivariate residential-workplace neighborhood effect when estimating the effect of proximity to fast-food establishments on body mass index. Stat Med. 2019 Mar 15;38(6):1013-1035. doi: 10.1002/sim.8039. PMID: 30460712; PMCID: PMC6377346.
  • Martinez-Camblor P, MacKenzie TA, Staiger DO, Goodney PP, O’Malley AJ. An instrumental variable procedure for estimating Cox models with non-proportional hazards in the presence of unmeasured confounding. Journal of the Royal Statistical Society, Series C (Applied Statistics). 2019, 985. doi: 10.1111/rssc.12341.
  • Martínez-Camblor P, Mackenzie T, Staiger DO, Goodney PP, O'Malley AJ. Adjusting for bias introduced by instrumental variable estimation in the Cox proportional hazards model. Biostatistics. 2019 Jan 1;20(1):80-96. doi: 10.1093/biostatistics/kxx062. PMID: 29267847.
  • Columbo JA, Martinez-Camblor P, MacKenzie TA, Staiger DO, Kang R, Goodney PP, O’Malley AJ. A comparative analysis of long-term mortality after carotid endarterectomy and carotid stenting. J Vasc Surg. 2019 Jan;69(1):104-109. doi: 10.1016/j.jvs.2018.03.432. PMID: 29914828; PMCID: PMC6295272.
  • MacKenzie TA, O'Malley AJ, Bekelis K. Reporting of baseline characteristics to accompany analysis by instrumental variables. Epidemiology. 2018 Nov;29(6):817-820. doi: 10.1097/EDE.0000000000000914. PMID: 30188381; PMCID: PMC6362835.
  • Bobak CA, Barr PJ, O'Malley AJ. Estimation of an inter-rater intra-class correlation coefficient that overcomes common assumption violations in the assessment of health measurement scales. BMC Med Res Methodol. 2018;18(1):93. Published 2018 Sep 12. doi:10.1186/s12874-018-0550-6
  • Columbo JA, Martinez-Camblor P, MacKenzie TA, Staiger DO, Kang R, Goodney PP, O'Malley AJ. Comparing long-term mortality after carotid endarterectomy vs carotid stenting using a novel instrumental variable method for risk adjustment in observational time-to-event data. JAMA Netw Open. 2018 Sep 7;1(5):e181676. doi: 10.1001/jamanetworkopen.2018.1676. Erratum in: JAMA Netw Open. 2018 Oct 5;1(6):e184055. PMID: 30646140; PMCID: PMC6324509.
  • An C, O'Malley AJ, Rockmore DN. Referral paths in the U.S. physician network. Appl Netw Sci. 2018;3(1):20. doi: 10.1007/s41109-018-0081-4. PMID: 30839747; PMCID: PMC6214314.
  • Aschbrenner KA, Bobak C, Schneider EJ, Naslund JA, Brunette MF, O'Malley AJ. Egocentric social networks and smoking among adults with serious mental illness. Transl Behav Med. 2018 Jul 17;8(4):531-539. doi: 10.1093/tbm/ibx014. PMID: 30016519.
  • Moen EL, Bynum JP, Austin AM, Skinner JS, Chakraborti G, O'Malley AJ. Assessing variation in implantable cardioverter defibrillator therapy guideline adherence with physician and hospital patient-sharing networks. Med Care. 2018 Apr;56(4):350-357. doi: 10.1097/MLR.0000000000000883. PMID: 29419707; PMCID: PMC5851832.
  • An C, O'Malley AJ, Rockmore DN, Stock CD. Analysis of the U.S. patient referral network. Stat Med. 2018 Feb 28;37(5):847-866. doi: 10.1002/sim.7565. Epub 2017 Dec 4. PMID: 29205445; PMCID: PMC5799011.
  • Landon BE, Keating NL, Onnela JP, Zaslavsky AM, Christakis NA, O'Malley AJ. Patient-sharing networks of physicians and health care utilization and spending among medicare beneficiaries. JAMA Intern Med. 2018 Jan 1;178(1):66-73. doi: 10.1001/jamainternmed.2017.5034. PMID: 29181504; PMCID: PMC5833496.
  • Choi J, O’Malley AJ. Estimating the causal effect of treatment in observational studies with survival time endpoints and unmeasured confounding. Journal of the Royal Statistical Society, Series C (Applied Statistics), 2017, 66, 159-185. PMID: 30686843.
  • Neelon B, O’Malley AJ, Smith VA. Modeling zero-modified count and semicontinuous data in health services research, part 2: Case studies. Statistics in Medicine, 2016, 35 (27), 5094-5112. doi: 10.1002/sim.7063. PMID: 27500973.
  • Neelon B, O’Malley AJ, Smith VA. Modeling zero-modified count and semicontinuous data in health services research, part 1: Background and overview. Statistics in Medicine, 2016, 35 (27), 5070-5093. doi: 10.1002/sim.7050. PMID: 27500945.
  • O’Malley AJ, Zaslavsky AM. Optimal small-area estimation and design when nonrespondents are subsampled for follow-up. Journal of Survey Statistics and Methodology. 2016 March; 4(1): p. 2–21.
  • Moen EL, Fricano-Kugler CJ, Luikart BW, O'Malley AJ. Analyzing clustered data: Why and how to account for multiple observations nested within a study participant? PLoS One. 2016 Jan 14;11(1):e0146721. doi: 10.1371/journal.pone.0146721. PMID: 26766425; PMCID: PMC4713068.
  • Moen EL, Austin AM, Bynum JP, Skinner JS, O’Malley AJ. An analysis of patient-sharing physician networks and implantable cardioverter defibrillator therapy. Health Services and Outcomes Research Methodology, 2016, 16, 132-153. PMID: 27597812.
  • O'Malley AJ, Zelevinsky K, He Y, Busch AB. Do patients at sites with high RCT enrollment propensity have better outcomes? Med Care. 2015 Nov;53(11):989-95. doi: 10.1097/MLR.0000000000000429. PMID: 26465127; PMCID: PMC4672722.
  • Busch AB, He Y, Zelevinsky K, O'Malley AJ. Predicting participation in psychiatric randomized controlled trials: Insights From the STEP-BD. Psychiatr Serv. 2015 Aug 1;66(8):817-23. doi: 10.1176/appi.ps.201300557. PMID: 25828873; PMCID: PMC4888778.
  • O'Malley AJ, Paul S. Using retrospective sampling to estimate models of relationship status in large longitudinal social networks. Comput Stat Data Anal. 2015 Feb 1;82:35-46. doi: 10.1016/j.csda.2014.08.001. PMID: 26692600; PMCID: PMC4673682.
  • O'Malley AJ, Elwert F, Rosenquist JN, Zaslavsky AM, Christakis NA. Estimating peer effects in longitudinal dyadic data using instrumental variables. Biometrics. 2014 Sep;70(3):506-15. doi: 10.1111/biom.12172. PMID: 24779654; PMCID: PMC4213357.
  • MacKenzie TA, Tosteson TD, Morden NE, Stukel TA, O'Malley AJ. Using instrumental variables to estimate a Cox's proportional hazards regression subject to additive confounding. Health Serv Outcomes Res Methodol. 2014 Jun;14(1-2):54-68. doi: 10.1007/s10742-014-0117-x. PMID: 25506259; PMCID: PMC4261749.
  • Paul S, O'Malley AJ. Hierarchical longitudinal models of relationships in social networks. J R Stat Soc Ser C Appl Stat. 2013 Oct;62(5):705-722. doi: 10.1111/rssc.12013. PMID: 24729637; PMCID: PMC3979311.
  • O'Malley AJ. The analysis of social network data: an exciting frontier for statisticians. Stat Med. 2013 Feb 20;32(4):539-55. doi: 10.1002/sim.5630. PMID: 23023735; PMCID: PMC3553267.
  • O'Malley AJ. Instrumental variable specifications and assumptions for longitudinal analysis of mental health cost offsets. Health Serv Outcomes Res Methodol. 2012 Dec;12(4):254-272. doi: 10.1007/s10742-012-0097-7. PMID: 23226968; PMCID: PMC3515775.
  • O'Malley AJ, Cotterill P, Schermerhorn ML, Landon BE. Improving observational study estimates of treatment effects using joint modeling of selection effects and outcomes: The case of AAA repair. Med Care. 2011 Dec;49(12):1126-32. doi: 10.1097/MLR.0b013e3182363d64. PMID: 22011709; PMCID: PMC3979312.
  • O'Malley AJ, Christakis NA. Longitudinal analysis of large social networks: Estimating the effect of health traits on changes in friendship ties. Stat Med. 2011 Apr 30;30(9):950-64. doi: 10.1002/sim.4190. PMID: 21287589; PMCID: PMC3079434.
  • Neelon B, O'Malley AJ, Normand SL. A bayesian two-part latent class model for longitudinal medical expenditure data: Assessing the impact of mental health and substance abuse parity. Biometrics. 2011 Mar;67(1):280-9. doi: 10.1111/j.1541-0420.2010.01439.x. PMID: 20528856; PMCID: PMC4445417.
  • O'Malley AJ, Marsden PV. The analysis of social networks. Health Serv Outcomes Res Methodol. 2008 Dec 1;8(4):222-269. doi: 10.1007/s10742-008-0041-z. PMID: 20046802; PMCID: PMC2799303.
  • O’Malley AJ, Zaslavsky AM. Domain-level covariance analysis for multi-level survey data with structured nonresponse. Journal of the American Statistical Association. 2008 Dec; 103(484): p. 1405-418.
  • O’Malley AJ, Zaslavsky AM. Variance-covariance functions for domain means of ordinal survey items. Survey Methodology. 2006; 31: p. 169-182.
  • O'Malley AJ, Normand SL. Likelihood methods for treatment noncompliance and subsequent nonresponse in randomized trials. Biometrics. 2005 Jun;61(2):325-34. doi: 10.1111/j.1541-0420.2005.040313.x. PMID: 16011678.