# [EpiData-list] problems with calculations during double entry

epidata-list at lists.umanitoba.ca epidata-list at lists.umanitoba.ca
Fri Oct 14 05:52:00 CDT 2005

```Hi,

I have a problem with results of calculation during double entry. During
double entry, all calculations give same results as first entry except only
for few subjects. I checked my formulae with other software and they look
OK. This bug is not systematic that’s why I have difficulties finding
errors. I don’t understand why this bug appears only for few subjects. They
have not the same characteristics.

Who can tell me what king of error it could be, because I don’t know anymore
what to looking for?

Below, calculations :

pspef
AFTER ENTRY
IF (sex = 1) and (height < 162.6) THEN
pspdpef=(height * 0.073) - 5.98
ENDIF
IF (sex = 1) and (height > 162.5) THEN
pspdpef=(height * 0.125) - 13.14
ENDIF
IF (sex = 0) and (height < 152.6) THEN
pspdpef=(height * 0.079) - 6.79
ENDIF
IF (sex = 0) and (height > 152.5) THEN
pspdpef=(height * 0.064) - 3.94
ENDIF
IF (sex = 1) THEN
pssdcpef=(pspef - pspdpef) / (pspdpef * 0.18)
ENDIF
IF (sex = 0) THEN
pssdcpef=(pspef - pspdpef) / (pspdpef * 0.2)
ENDIF
psppef=(pspef/pspdpef)*100
END
END

pspdpef
NOENTER
END

pssdcpef
NOENTER
END

psppef
NOENTER
END

Example : sex = 1 , height = 132.8, pspef = 4.90

First entry (good results)
pspdpef = 3.71
pssdcpef = 1.78
psppef = 132.1

Double entry
pspdpef = 3.71
pssdcpef = -1.15
psppef = 79.2

Marie-Pierre

Strippoli Marie-Pierre
Institut of social and preventive medicine
Department of Epidemiology and Biostatistic
Paediatric Epidemiology
Finkenhubelweg 11
3012 Bern
Tel: +41 (0)31 631 35 07
Fax: +41 (0)31 631 35 20
http://www.ispm.unibe.ch

```