Lab 7.1

Use the CHF dataset for this lab.

Create a separate tab in the spreadsheet for each sample selected.

#1 and #2 use only rows of data with DRG = 292. The first step should be creating a new tab in the spreadsheet with ONLY DRG 292 rows.

Random Sampling

- Select a simple random sample of 30 patients from DRG 292 set using two methods
- Use the ‘rand()’ function
- Use the random number generator in the Data Analysis Add-in using your birthday as the seed (mmdd)

- Select a systematic random sample from DRG 292
- Select a stratified sample from the CHF data using the MS-DRG to define the strata and an overall sample size of 30

Determination of Sample Size

- Use RATStats to determine sample size required for estimating 95% confidence interval for population mean LOS with 10% precision for MS-DRG 292
- Use results from random sample above as a probe sample
- Do a print screen of the results and place it on a new spreadsheet labeled RATSTATS.
- What impact does precision/confidence level have on required sample size?

- If you have a MAC and cannot use the above program, try to locate a sample size generator on the internet to use for this assignment. If you locate one, please provide the website that you have used for the calculation.

Using the CHF Data, complete Lab 7.1. Please see the YouTube videos available for the use of RATSTATS. Here’s the link to the RATSTATS software.