Loading in 2 Seconds...
Loading in 2 Seconds...
National Hospital Discharge Survey: A Hands-On Workshop Using Public-Use Data Files Michelle N. Podgornik, MPH 2006 Data Users Conference July 11, 2006 8:30am-10:00am Session #23
NHDS Background • National probability survey of discharges from non-federal, short-stay hospitals in the United States • Conducted annually since 1965 • Latest data available: 2004
NHDS Design • Three-Stage Design • Primary Sampling Units (PSUs) • Hospitals • Discharges
Patient Data • Age • Sex • Race • Source of payment • Discharge status • Marital status
Facility Data • Geographic region • Bed size • Ownership
Medical Data • Diagnoses • Surgical and non-surgical procedures • International Classification of Diseases, 9th Revision, Clinical Modification (ICD-9-CM)
Additional Data • Days of care • Month of discharge • Diagnosis-related groups (DRGs) • Analysis weight
Session Goals • At the end of this session, you will be able to: • Understand some of the advantages and limitations of using downloadable NHDS data • Successfully download data files from the Internet and create a SAS dataset for analysis • Perform simple analyses using SAS
Using Online Data Files • Advantages • Obtain current data and data file documentation • Obtain diagnosis-related group (DRG) information
Using Online Data Files • Limitations • Only single-year data files from 1996 through 2004 are available • Variables necessary to run SUDAAN are not publicly available
Downloading Data • Download data and data file layout from the NCHS website - http://www.cdc.gov/nchs • Fixed width ASCII files are available for each data collection year since 1996
Extracting Data • Downloaded data files must be “unzipped” using extraction software (e.g. WinZip) • Your computer may have extraction software pre-installed; if not, a free evaluation version of WinZip is available at: http://www.winzip.com/downwzeval.htm?wzdm
Data File Documentation • Each document includes: • A description of the NHDS, including survey methodology • File layout • Parameters and equations used to calculate relative standard errors, a measure of the reliability of an estimate
Data File Documentation ( - cont’d - ) • Each document also includes: • ICD-9-CM code changes • Census population estimates • Unweighted and weighted frequencies of selected variables • Medical Abstract Form