a little, or not at all. These responses were subsequently

assigned values of two, one, and zero respectively. The sum

of values for each of the 18 responses was taken as the

measure of co-morbidity.

 The development of this scale for this study was based

on the premise that physical conditions other than cancer

often play an important role in the morbidity and mortality

of cancer patients. However, information about these

conditions is generally not included in studies of important

medical and disease variables in the survival of cancer

patients. In this case, this information was not available

on the cases of deceased cancer patients and could not,

therefore, be studied along with other disease variables

through the regression analysis used to determine survival

expectations.

 The Index of Co-Morbidity was based on a clinical

evaluation of the patients' health by their primary physician

and, as such, a good deal was left to the judgement of each

physician. No arrangements were made with the physicians

involved for a cross-evaluation of the sample, and as a

result, the error variance from interscorer differences was

not evaluated.

The organization of data

 All information collected on the subjects in the sample

was recorded in a code book. This is included as Appendix D.