Table of Contents

Component Description

Sera from residual specimens from NHANES 2001-2002 participants were tested for levels of cancer antigen 125 (CA125) and cancer antigen 15.3 (CA15.3). The results for CA125 in this data release are reported as U/mL. The results for CA15.3 are reported as mU/mL.

Eligible Sample

Female participants age 20+ who consented to storing their samples for future research and had stored samples from 2001-2002.

Description of Laboratory Methodology

All measurements were performed in the Genital Tract Biology Laboratory (Brigham and Women’s Hospital, Lab Director) following pre-analytic, analytic, and post-analytic standardized operational procedures (SOPs) established under the Laboratory director and special chemistry accreditation by the College of American Pathologists. The lab used the Meso Scale Discovery (MSD) (Gaithersburg, MD) electrochemiluminescence immunoassay platform. Quality control (QC) pools were prepared and split into multiple aliquots. To establish inter-and intra-plate variability, one aliquot of this pool was repeatedly tested on each assay plate. A coefficient of variation of < 25% was set as a threshold for acceptance of the data.

In further detail, the following assays and methodology were applied:

Human CA125 (single spot, catalog number K151WC)

The linearity range for the CA125 was 10,000–0.6 U/ml (low limit of detection (LLD) 0.286 U/ml). All samples were tested undiluted and four samples were repeatedly tested to verify their top or bottom outlier values. The QC pool for this assay was prepared by pooling a small volume (5 ul/ sample) from over 2000 serum samples which had shown well measurable levels of CA125 in a prior study using the MSD platform.

Human Prototype CA15.3 (single spot catalog number N45ZA-1)

The linearity range for the CA15.3 assay was 12,500–0.76 mU/mL (LLD=0.483 mU/ml).

All samples were tested at 25- or 50-fold dilution and retested at 250-fold dilution if the first dilution resulted in values above the linearity of the assay. The QC pool for this assay was prepared by pooling 1.5 ml per sample from seven samples from a pilot study previously tested on the same assay and found to have high levels. All samples were tested at a 25-fold dilution chosen after multiple dilutions were screened to fit the assay linearity range, and to correspond to the lowest dilution of the study samples. Two CA15.3 assay plates were re-tested due to QC failure in the first run.

The unblinded quality control sample pool repeatedly tested on every assay plate showed the following inter-plate CV and min–max range (mean) of intraplate CV of the three QC dilutions tested: (i) CA125, 13% inter-plate CV and 0.5%–22% (7%) intraplate CV; (ii) CA15.3: 19% inter-plate CV and 0%–17% (4%) intraplate CV.

Laboratory Quality Assurance and Monitoring

The acceptable QC pool variation was set to 25%. Back fit analysis of each calibrator was also set to 25% acceptable level.  Outliers were confirmed by repeated testing and samples outside the linearity range of each assay were repeatedly tested at adjusted dilution to produce acceptable value.

Data Processing and Editing

Data was compiled into a database after all the assays were completed and passed quality control criteria. The data were not edited.

Data Access: All data will be made publicly available.

Analytic Notes

Results were measured as U/mL for CA125 and mU/mL for CA15.3

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.

References

Codebook and Frequencies

SEQN - Respondent sequence number

Variable Name:
SEQN
SAS Label:
Respondent sequence number
English Text:
Respondent sequence number.
Target:
Females only 20 YEARS - 150 YEARS

SSCA125 - Cancer antigen 125 (U/mL)

Variable Name:
SSCA125
SAS Label:
Cancer antigen 125 (U/mL)
English Text:
Cancer antigen 125 (U/mL)
Target:
Females only 20 YEARS - 150 YEARS
Code or Value Value Description Count Cumulative Skip to Item
0.73 to 569.37 Range of Values 2525 2525
. Missing 0 2525

SSCA153 - Cancer antigen 15.3 (mU/mL)

Variable Name:
SSCA153
SAS Label:
Cancer antigen 15.3 (mU/mL)
English Text:
Cancer antigen 15.3 (mU/mL)
Target:
Females only 20 YEARS - 150 YEARS
Code or Value Value Description Count Cumulative Skip to Item
95.83 to 704915.87 Range of Values 2525 2525
. Missing 0 2525