If you insist on doing this analysis yourself, you might want to get hold of the book, Logistic Regression, by Kleinbaum. Actually, you should consult with a biostatistician if you want your results to be valid.
-Jay Ronan O'Leary wrote: > > Hi > > I hope someone here may be able to point me in the right direction. > > I am an undergraduate medical student doing a project which aims to look at > whether information obtained in the diagnosis of certain forms of cancer can > predict the presence of lymph node metastasis. > > A "core biopsy" of tissue is removed from the cancer lump either using > imaging techniques or palpation to ensure that the needle passes through the > tumour. These pieces of tissue are examined by a pathologist who determines > whether cancer is present and grades it accordingly. I would like to ask the > following question with the information obtained: Is there any information > in the core which can either predict the presence of disease positive lymph > nodes or the absence? Lymph node disease is detected at subsequent surgery. > I also hope to combine this with measurement of tumour size by clinical or > radiological techniques. > Therefore the fields I am using from my data set are: > > Positive Lymph Nodes (yes/no or 1/0); grading criteria A (a numerical scale > 1-3), B (1-3), C (1-3) and tumour size (diameter in mm). > > I have been advised to use binary logistical regression and have been > looking at Minitab, but have not really got that far despite reading every > text book I can find with a chapter on this. I am beginning to think that > the key problem is that each variable is not binary, they all have 3 values > and the size can be a wide range, however, I can categorise this. > > Basically I want to identify if any of the criteria alone or preferably in > combination can predict lymph node disease. How do I interpret the results > from Minitab. Is it possible to convert the results to % so for example I > could say A1 B<2 C1 and tumour size less than 5mm means you are 5% likely to > have mets. > > Is there anyone who is able to help me out, it shouldn't take more than a > couple of emails. > > Thanks in advance > > Ronan > > P.S. Help on the best way to assemble the data and run the dialogues in > Minitab would also be a great help. > > --- > > Checked by AVG anti-virus system (http://www.grisoft.com). > Version: 6.0.344 / Virus Database: 191 - Release Date: 03/04/2002 . . ================================================================= Instructions for joining and leaving this list, remarks about the problem of INAPPROPRIATE MESSAGES, and archives are available at: . http://jse.stat.ncsu.edu/ . =================================================================
