Response to O’Rourke

Della Gibson, Angela Harvey, and Mahesh Parmar Medical Research Council, Cambridge, United Kingdom

We thank Dr. O’Rourke for his letter in which he refers to our paper “Is Double

Data Entry Necessary? The CHART Trials” [l]. In our opinion he is confusing dishonesty with innocent mistakes. In our working environment we consider that

there is usually little personal gain in somebody entering incorrect data deliber- ately, and in fact cases of actual fraud, although often celebrated, are still thank- fully rare in publicly funded scientific research. Thus, our aim is to minimize innocent mistakes. We consider that this is best and most economically done by

a data manager performing single-data entry. This individual is entirely responsible for all aspects of the data for a particular trial, including receipt of the forms, checking forms, data entry, and analysis. As our study illustrates, we think that the data are more likely to be accurately entered onto the computer database in this way than by asking two people who know very little of the trial to both perform data entry.

Nevertheless, a recent development within our office is that we intend to start performing routine audits on all trials, for a random sample of important variabIes,

on a regular basis. In contrast, we note that for several new pharmaceutically funded trials that we are conducting, we have had to change our practice, whereby good clinical practice constraints have resulted in the data for these trials being

entered twice by two members of staff other than the trial coordinator.

REFERENCE

1. Gibson D, Harvey AJ, Everett V, Parmar MKB, on behalf of the CHART Steering Committee: Is double data entry necessary? The CHART trials. Controlled Clin Trials 15:482-488, 1994

Contded C&cd Trials 17:71 (1996) 0 Elsevier Science Inc. 1996 655 Avenue of the Americas, New York, NY 10010

0197.2456/96/$15.00 SSDI 0197-2456(95)00151-6