Description Usage Format Details Source References Examples
Data come from the 1991 Arizona cardiovascular patient files. A subset of the fields was selected to model the differential length of stay for patients entering the hospital to receive one of two standard cardiovascular procedures: CABG and PTCA. CABG is the standard acronym for Coronary Artery Bypass Graft, where the flow of blood in a diseased or blocked coronary artery or vein has been grafted to bypass the diseased sections. PTCA, or Percutaneous Transluminal Coronary Angioplasty, is a method of placing a balloon in a blocked coronary artery to open it to blood flow. It is a much less severe method of treatment for those having coronary blockage, with a corresponding reduction in risk.
1 |
A data frame with 3589 observations on the following 6 variables.
los
length of hospital stay
procedure
1=CABG;0=PTCA
sex
1=Male; 0=female
admit
1=Urgent/Emerg; 0=elective (type of admission)
age75
1= Age>75; 0=Age<=75
hospital
encrypted facility code (string)
azpro is saved as a data frame. Count models use los as response variable. 0 counts are structurally excluded
1991 Arizona Medpar data, cardiovascular patient files, National Health Economics & Research Co.
Hilbe, Joseph M (2007, 2011), Negative Binomial Regression, Cambridge University Press Hilbe, Joseph M (2009), Logistic Regression Models, Chapman & Hall/CRC
1 2 3 4 5 6 7 |
Loading required package: msme
Loading required package: MASS
Loading required package: lattice
Loading required package: sandwich
Call:
glm(formula = los ~ procedure + sex + admit, family = poisson,
data = azpro)
Deviance Residuals:
Min 1Q Median 3Q Max
-3.1987 -1.1451 -0.4756 0.5331 12.4784
Coefficients:
Estimate Std. Error z value Pr(>|z|)
(Intercept) 1.49140 0.01539 96.91 <2e-16 ***
procedure 0.95738 0.01218 78.61 <2e-16 ***
sex -0.13022 0.01179 -11.04 <2e-16 ***
admit 0.33307 0.01210 27.52 <2e-16 ***
---
Signif. codes: 0 '***' 0.001 '**' 0.01 '*' 0.05 '.' 0.1 ' ' 1
(Dispersion parameter for poisson family taken to be 1)
Null deviance: 16265.0 on 3588 degrees of freedom
Residual deviance: 8968.9 on 3585 degrees of freedom
AIC: 22483
Number of Fisher Scoring iterations: 5
(Intercept) procedure sex admit
4.4433339 2.6048728 0.8779003 1.3952480
Add the following code to your website.
For more information on customizing the embed code, read Embedding Snippets.