Abdus S Wahed, PhD

My current major research interest is in personalized medicine – development of statistical methods for testing dynamic treatment regimes (adaptive treatment strategies) through sequentially randomized designs, for screening viable treatment regimes from observational data, and for identifying important variables for forming dynamic treatment regimes. Other methodological research interest includes multivariate ordinal longitudinal data analysis, survival analysis in the presence of misclassified events, and analysis of variance for censored survival data, length biased data, and joint modeling of longitudinal and time-to-event data measured with error. My collaborative research interest includes development of multi-stage depression treatment regimes, sequential treatment decisions in depression treatment, development of risk scores for complications in bariatric surgery, analysis of outcomes in hepatitis B and C clinical trials and cohort studies, and weight loss in young adults.

Ph.D., Statistics (2003), North Carolina State University, Raleigh, NC
M.A., Mathematical Statistics (2000), Ball State University, Muncie, IN
M.Sc., Statistics (1994), University of Dhaka, Bangladesh
B.Sc., Statistics (1992, Minor: Economics and Mathematics), University of Dhaka, Bangladesh

Linear Models

Estimation Theory

Likelihood Theory

1. *Jiang, Z, Liu, Y, Wahed, AS, and Molenberghs, G (2018). Joint modeling of multiple ordinal adherence outcomes via generalized estimating equations with flexible correlation structure.
Statistics in medicine 37 (6), 983-995.
2. *Adeniji, AK, Hsu, JY, Wahed, AS (2018). Estimation of discrete survival function for error-prone diagnostic tests. Pharmaceutical statistics 17 (1), 74-89.

3. Yavuz, I, Cheng, Y, and Wahed, AS (2018). Estimating the Cumulative Incidence Function of Dynamic Treatment Regimes. Journal of Royal Statistical Society, Series A. 181 (1), 85-106.

5. *Hsu JY, Wahed AS (2017). Weighted generalized estimating equations for response-adaptive treatment regimes in two-stage longitudinal studies. Journal of Statistical Research 51(1): 79-100

6. Xu, Y, Mller, P, Wahed, AS, and Thall, PF. (2016). Bayesian Nonparametric Estimation for Dynamic Treatment Regimes with Sequential Transition Times; In Press, J. of the Am. Stat. Assoc. 111 (515), 921-950.

7. *Sampene, E. and Wahed, AS (2016). A Relatively Simple Efficient Estimator for Relative Risk in Case-Cohort Studies. Journal of Statistical Research 2016, Vol. 48-50, No. 2, pp. 37-54

8. *Marron, MM, and Wahed, AS (2016). Teaching Missing Data Methodology to Undergraduates Using a Group-Based Project Within a Six-Week Summer Program. Journal of Statistics Education 24 (1), 8-15.

9. Jaman, A, Latif, AHMM, Bari, W, and Wahed, AS (2016). A determinant-based criterion for working correlation structure selection in generalized estimating equations. Statistics in Medicine, Volume 35, Issue 11, 20 May 2016, Pages 18191833.

10. *Ogbagaber, SB, Karp, J, and Wahed, AS (2016). Design of sequentially randomized trials for testing adaptive treatment strategies. Statistics in Medicine. Volume 35, Issue 6, pp 840-858.

13. Huang, X, Ning, J,Wahed, AS (2014). Optimization of individualized dynamic treatment regimes for recurrent diseases. Statistics in medicine 33.14 (2014): 2363-2378.

14. *Kidwell, K, Ko, JH, and Wahed, AS (2014). Inference for the median residual life function in sequential multiple assignment randomized trials. Statistics in medicine 33.9 (2014): 1503-1513.

16. *Tang, X, and Wahed, AS (2014). Cumulative Hazard Ratio Estimation for Treatment Regimes in Sequentially Randomized Clinical Trials. Statistics in Biosciences, 10.1007/s12561-013-9089-6

17. *Kidwell, KM and Wahed, AS (2013). Weighted Log-rank Statistic to Compare Shared-Path Adaptive Treatment Strategies. Biostatistics 2013 Apr;14(2):299-312.

18. Wahed, AS, Thall, PF(2013 ). Evaluating Joint Eects of Induction-Salvage Treatment Regimes on Overall Survival in Acute Leukemia. Journal of Royal Statistical Society, Series C. Appl. Statist. (2013) 62, Part 1, pp. 6783

20. *Ko, JH, and Wahed, AS (2012). Up-front vs. Sequential Randomizations for Inference on Adaptive Treatment Strategies. Statistics in Medicine, Volume 31, Issue 9, pages 812830

25. *Feng, W and Wahed, AS (2009). Sample Size for Two-Stage Studies with Maintenance Therapy. Statistics in Medicine, 2009; 28: 2028-2041

26. Wahed, AS ,Luong, T, and Jeong, J-H (2009). A new generalization of Weibull distribution with application to a breast cancer data set. Statistics in Medicine, 2009; 28: 2077-2094

27. Wahed, AS (2009). Estimation of survival quantiles in two-stage randomization designs, Journal of Statistical Planning and Inference 139 (2009) 2064-2075.

28. *Feng, W and Wahed, AS (2008). A supremum log rank test for comparing adaptive treatment strategies and corresponding sample size formula, Biometrika. 95, 3, pp. 695-707.

31. Wahed, AS and Tsiatis, AA (2006). Semi-parametric Efficient Estimation of The Survival Distribution for Treatment Policies in Two-Stage Randomization Designs in Clinical Trials with Censored Data. Biometrika Vol 93: pp. 147-161.

32. Wahed, AS (2006). Bayesian Inference Using Burr Model Under Asymmetric Loss Function: An Application to Carcinoma Survival Data. Journal of Statistical Research, 2006, Vol. 40, No. 1, pp. 45-57.