• Component Description
• Eligible Sample
• Description of Laboratory Methodology
• Data Processing and Editing
• Laboratory Quality Assurance and Monitoring
• Analytic Notes
• Codebook
  • SEQN - Respondent sequence number
  • URXPREG - Pregnancy test result

National Health and Nutrition Examination Survey

2009-2010 Data Documentation, Codebook, and Frequencies

Pregnancy Test - Urine (UCPREG_F)

Data File: UCPREG_F.xpt

First Published: September 2011

Last Revised: October 2014

Component Description

A urine test was performed on survey participants 8 years and older. If the urine pregnancy test was positive on any female participants aged 8 -17 years, the result was confirmed using a serum test. All positive test results excluded pregnant women from the DXA and cardiovascular fitness components of the mobile examination center.

Eligible Sample

A pregnancy test was completed on female participants aged 12–59 years and menstruating females aged 8–11 years. However, due to disclosure risks only females between 20 and 44 have urine pregnancy results in this file.

Description of Laboratory Methodology

Urine and serum specimens were tested in the NHANES mobile examination centers. Detailed specimen collection and processing instructions are discussed in the NHANES Laboratory/Medical Technologists Procedures Manual (LPM).

The Icon 25 hCG test kit (Beckman Coulter) is a rapid chromatographic immunoassay for the qualitative detection of human chorionic gonadotropin (hCG) in urine or serum to aid in the early detection of pregnancy. The test utilizes a combination of monoclonal and polyclonal antibodies to selectively detect elevated levels of hCG in urine or serum.

A detailed description of the laboratory method used can be found on the NHANES website.

Data Processing and Editing

Instructions on data processing and editing can be found on the NHANES website.

Laboratory Quality Assurance and Monitoring

The NHANES quality control and quality assurance protocols (QA/QC) meet the 1988 Clinical Laboratory Improvement Amendments mandates. Detailed QA/QC instructions are discussed in the NHANES Laboratory/Medical Technologists Procedures Manual (LPM). Read the General Documentation on Laboratory Data file for detailed QA/QC protocols.

A detailed description of the quality assurance and quality control procedures can be found on the NHANES website.

Analytic Notes

Exam sample weights should be used for analyses.

Please refer to the NHANES Analytic Guidelines and the on-line NHANES Tutorial for further details on the use of sample weights and other analytic issues.

Codebook and Frequencies