Use information about a variable vertically

[Kezaar]

Hello,

I have got a problem with SPSS that I can't solve by myself.

In my data, there is a variable which encodes the lenght of hospitalisation (from 0 to 4 000 days), and another variable which encodes the result of one diagnostic test (positive/ negative, 1/0).

I would like to compute the sum of all the negative results for one given lenght of hospitalisation, and the sum of all the positive results. This way, I will be able to get the yield of my diagnostic test (sum of positives / (sum of positive + sum of negative) for each lenght of hospitalisation (maybe just from 0 days to 30 days).

I can easily compute new variables when it adds data horizontally in SPSS but I don't know how to do it vertically in my case.

I will be very grateful if you can help me !

[Mike Z.]

One way is to use
Analyze->Reports

Then move over Length of Hospitalization into the Variable box,
and move over Result of Diagnostic Test into the Grouping Variable box.

Then click the "Statistics..." button, and move over "Sum" from the "Statistics:" list to the "Cell Statistics:" list.

Then press "Continue" and "OK" to see the sums.

[Kezaar]

Thank you for your quick answer !