• 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

2003-2004 Data Documentation, Codebook, and Frequencies

Pregnancy Test - Urine (UC_C)

Data File: UC_C.xpt

First Published: January 2006

Last Revised: April 2006

Component Description

The dual energy x-ray absorptiometry (DXA) scan was performed on survey participants 8 years and older. The scan involves radiation exposure to the whole body. Pregnant women are excluded from the DXA, bioelectrical impedance, and cardiovascular fitness components of the mobile examination center, so a urine pregnancy test was performed first. If the urine test results were positive for pregnancy, a serum pregnancy test was also performed.

Eligible Sample

A pregnancy test was completed on female participants aged 12–59 years and menstruating females aged 8–11 years.

Description of Laboratory Methodology

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

Urine and serum specimens were tested in the NHANES mobile examination centers. Detailed specimen collection and processing instructions are discussed in the NHANES LPM.

Detailed instructions on specimen collection and processing 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 quality control and quality assurance instructions are discussed in the NHANES Laboratory/Medical Technologists Procedures Manual (LPM). Read the LABDOC 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

A pregnancy test was completed on female participants aged 12–59 years and menstruating females aged 8–11 years.

Codebook and Frequencies