The R code used for the data analysis and simulations in our manuscript (Díaz et al. 2018) had two errors, which we have corrected. All of the theoretical results in the paper are correct. It is our implementation of these in R code that had the errors, which impacts the data analysis and simulation results in Section 6. This erratum describes the errors and presents the updated results of the data analysis and simulations with the errors corrected. The two errors were (i) incorrect coding of the auxiliary variable H used in the TMLE estimator, and (ii) incorrect coding of time t as numeric instead of as a factor in the adjusted estimators. These were corrected and the updated code is available at (Díaz 2018a). The updated results, given below, are qualitatively similar to the original results (i.e., there are no changes to our conclusions in the paper) except for the following: the updated TMLE ( ˆ θadj,eff) confidence interval coverage probabilities ranged from 93 to 95% (previously 94–95%); the updated bias of the TMLE ˆ θadj,eff was sometimes larger but still small (at most 3%) as a fraction of the treatment effect (14.9 days) and had negligible influence on the mean squared error; the adjusted inverse probability weighted estimator ˆ θadj,ipw (which was not the focus of the paper) had larger variance in the updated results compared to the original results, leading to lower relative efficiency.
ASJC Scopus subject areas
- Applied Mathematics