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Editor, We thank Hu et al. for their interest in our work1 and their valuable comments.2 We are particularly grateful for the opportunity to correct a deficiency in our original presentation. In assessing the incidence of complications among our control and intervention groups, each discrete episode of nausea and pruritus was counted. Indeed, Fisher's exact test was used on the presence/absence (categorical data) of adverse effects, and the Mann-Whitney U test was used to examine differences in distributions when data was skew. Thus for nausea and pruritus, although collected as categorical data, the number of discrete episodes per patient were included in the analyses and the Mann-Whitney U test was used to test differences in the distributions. In addition, we wish to correct factual errors published in Table 2, namely the P values for both nausea and pruritus. The difference between groups in the number of discrete episodes of nausea did not reach statistical significance [Fisher's exact test, P = 0.76; Mann-Whitney U test, P = 0.318 with a median [IQR] of 1 [0 to 2] in the intervention group and 1 [0 to 3] in the control group]. A greater difference in the distribution of pruritus episodes was detected (Mann-Whitney U test, P < 0.001 with a median [IQR] of 1.5 [0 to 3] episodes for the control group and 0 [0] for the intervention group). The corrected Table should reflect this lack of significance in the incidence of nausea (P value NS) and a greater magnitude of difference for pruritus (P < 0.001). We regret these errors and understand that the best way of highlighting them may be through an Erratum. Acknowledgements relating to this article Assistance with the letter: none. Financial support and sponsorship: none. Conflicts of interest: none.