Peter: We have always double entered. We deal with relatively small datasets (n<100, usu.) and are looking for relatively small effect sizes. Consequently, the data values for each case/subject are crucial. A data entry error could destroy an effect which really exists or, alternatively, show us one that doesn't. The expense of avoiding this problem is miniscule compared to the ramifications of error. We have found that the DE module (DOS version) is a reliable tool. Different individuals enter and verify. Hope this helps. Jeff

Jeffrey R. Van Kirk Department of Psychiatry, MC-2103 University of Connecticut Health Center 263 Farmington Ave. Farmington, CT 06030 ph: 860-679-3613 fax: 860-679-1316 e-mail: VanKirk@Psychiatry.UCHC.EDU

-----Original Message----- From: Peter A. Vanable [SMTP:pvanable@YODA.BSD.UCHICAGO.EDU] Sent: Tuesday, December 01, 1998 9:55 AM To: SPSSX-L@UGA.CC.UGA.EDU Subject: norms for data checking/verification

Hello -- As many of you know, SPSS DE has a 'verify' mode, allowing users to do a second pass of data entry, where the computer beeps at the user if the value entered the second time around doesn't match what was entered the first time. This feature provides some added confidence that data entry errors are being kept to a minimum.

For a number of years, our research group has had staff members use this feature, at considerable time and cost to various projects. In talking to other colleagues here, I am finding that double entering of data is fairly unusual, i.e., most people just enter the data once and hope for the best.

My questions are:

1) How many of you actually go to the trouble of double entering your data (either using the "verify" mode or simply by having data entered twice in the spread sheet mode)?

2) Do others feel that the added benefit of double entering outweighs the costs in terms of the time it takes to do a second pass?

3) Assuming data re-entry/verification is done, how important is it that a different person enter the data the second time around.

I will appreciate any feedback on these questions... thanks very much!

- Peter Vanable

-- Peter Vanable, Ph.D. The University of Chicago Department of Psychiatry 5841 S. Maryland Avenue, M/C 3077 Chicago, IL 60637 773-702-1541 (U of C) 773-388-1600 (HBHC)