Treviño (1) has misunderstood our description of the feedback about blood glucose levels offered to patients in our trial of a real-time telemedicine system (2). He has also attributed a quotation from an article by Bode et al. (3) to our report (2). Treviño calls for the use of better statistical methods to deal with temporal correlations between the repeated glucose values used in real-time monitoring. While we have sympathy with this message, we do not wish to see our trial data misrepresented.
Patients using our telemedicine system received real-time feedback consisting of time series graphs and color-coded histograms of blood glucose measurements. They did not receive, as suggested in Treviño’s letter, information about means and SD of blood glucose measurements. This suggestion may have arisen from a misunderstanding about the application of statistical methods used in our study to analyze the A1C measurements, which were the primary outcome of the trial.
Treviño also attributes the following statement to our article: “Overtreating hypoglycemia has resulted in a marginally significant increase in the frequency of hyperglycemic excursions.” This was not an outcome of our trial, and the quoted text is from an article by Bode et al. (3). Unfortunately, this misattribution is repeated by Garg (4), who argues that “the fact that, using traditional finger-stick methods, patients ‘overtreating hypoglycemia’ suffer ‘unrecognized hypo- and hyperglycemia’ is precisely because intermittent monitoring with finger-sticks does not give them enough information.” In fact, in its correct context, the quotation on “overtreating hypoglycemia” from Bode et al. (3) describes an outcome observed during use of the Guardian continuous glucose monitoring system rather than finger-stick methods.
While we have followed this correspondence with interest, our trial is not a valid exemplar of the statistical issue discussed by Treviño (1), since patients were not presented with means or SDs of blood glucose. We hope that this confusion has not distracted from discussion of the important issue of the statistical analysis of blood glucose time series.
References
O.J.G. has received consulting fees from t+ Medical, a company that provides technology to assist patients with chronic diseases in their self-management. L.T. has served on an advisory panel for and holds stock in t+ Medical.
