We've wondered about this ourselves and I haven't seen it covered in any text. We also opted for reporting baseline stats on unimputed data because our missing data is mainly in one predictor variable, and indicate the observed n in a footnote or the table itself. Bill Howells, Wash U Med School, St Louis
-----Original Message----- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of DePuy, Venita Sent: Thursday, October 21, 2004 11:19 AM To: 'Balasubramani, G.K. '; ''[EMAIL PROTECTED]' ' Subject: RE: [Impute] Multiply Imputation - Descriptive Stats Hi Bala et al - In the varous MI papers we work on in my group, we typically provide baseline descriptive stats for the unimputed group. If that is not an option, consider using either the first imputed sample or the overall imputated values. The overall MI mean for a value is merely the mean of the 5 (or however many) means, one from each dataset. However, you typically want to reporta measure of variance. For the unimputed or 1st imputed sample method, you can just use std dev. For the overall imputed values, you need to use standard errors. Personally, I prefer using unimputed for the baseline descriptives and full imputation values in subsequent analyses . . . but I would say the main deciding factor is the amount of missingness in your data. If it's very large, you will probably want to use imputed values. Hope this helps! Venita -----Original Message----- From: Balasubramani, G.K. To: '[EMAIL PROTECTED]' Sent: 10/21/2004 12:05 PM Subject: [Impute] Multiply Imputation - Descriptive Stats Hello all, This is a basic question in relation to imputation. That is, the imputed data is an outcome variable, which is Hamilton depression rating scale. I am using the threshold to create an indicator of remission or not remission. After I imputed the data (say for 5 times) , how do I show the descriptive statistics? That is, the percentage with remission when data include imputed values. (Ex. Sex with remission , Employment status with remission, etc..). Can I take the mean of the 5 imputed data sets to create the indicator variable for remission? Is there any other way to present the descriptive using the imputed data? Thanks in advance. Bala <<ATT93287.txt>> _______________________________________________ Impute mailing list [EMAIL PROTECTED] http://lists.utsouthwestern.edu/mailman/listinfo/impute _______________________________________________ Impute mailing list [EMAIL PROTECTED] http://lists.utsouthwestern.edu/mailman/listinfo/impute
