Sara is an administrator whose responsibilities include a cardiac unit. Because congestive heart failure (CHF) is a high volume condition for her unit, she want to have a better understanding of some of the drivers of length of stay (LOS) for these patients. After a brief review of the literature, Sara find that several of the key factors affecting patient LOS for CHF are: the number of medications the patient is on upon admission, the duration of intravenous diuretics, and the number of comorbid conditions. Sara is also interested in whether gender affects LOS for her patient population. Sara ask a colleague whom she know to be familiar with statistics to perform separate, simple regression analyses regarding LOS and each of the factors of interest. Using the frameworkLOS = intercept + slope*key factor, her colleague presents she's with the following results:

LOS as a function of the number of medications upon admission:

• Intercept = 5.2
• Slope = 0.15

LOS as a function of the duration of intravenous diuretics:

• Intercept = 5.1
• Slope = 0.25

LOS as a function of the number of comorbid conditions:

• Intercept = 5.0
• Slope = 0.4

LOS as a function of gender (when the patient is a male):

• Intercept = 5.85
• Slope = 0.05

Demonstrate or explain an informal cheat sheet for Sara indicating the predicted LOS for each of the following:

1. What would LOS be for a patient admitted taking 0 prescription drugs? A patient taking 3 prescription drugs? A patient taking 6 prescription drugs?
2. What would LOS be for a patient receiving intravenous diuretics for 0 days? A patient receiving intravenous diuretics for 2 days? A patient receiving intravenous diuretics for 4 days?
3. What would LOS be for a patient who has 0 comorbid conditions? A patient who has 3 comorbid conditions? A patient who has 6 comorbid conditions?
4. What would the LOS be for a patient who is male? A patient who is female? Use a "dummy variable" to isolate the impact of gender on LOS. To demonstrate or explain, assign males the value of 1 and females the value of 0 when conducting your analysis.

On the cheat sheet, describe which of the factors has the biggest impact on LOS and any insights from Sara analysis that improve her understanding of some of the drivers of LOS for her CHF patients.

Assignment 4.3 Regression Analysis and Predictions Name: 1. LOS for Patient Taking x Prescription Drugs 2. LOS for Patient Receiving Intravenous Diuretics for 3. LOS for Patient with x Comorbid Conditions mm -- Which of the factors has the biggest impact on LOS, and what insights from your analysis have improved your understanding of some drivers of LOS for your CHF patients? NOTE: GENDER IS KNOWN AS A \"DUMMY\" VARIABLE AND SHOULD BE INTERPRETED AS 1I0 WITH THE REFERENCE GROUP (i.e., MALE) TAKING THE VALUE 1