A longitudinal replicate study of immunosuppressive drugs: a College of American Pathologists study.

Journal Article (Journal Article;Multicenter Study)

OBJECTIVE: To identify the sources of analytical variation for cyclosporine and tacrolimus in a 3-year longitudinal study. DESIGN: Two pools of whole blood were spiked with cyclosporine and tacrolimus, respectively. One aliquot of cyclosporine and 2 of the tacrolimus pool were distributed in the first and last mailing for years 1999 to 2001. For both drugs, the total variance for each method was partitioned into within- and between-laboratory components. SETTING: The A and C mailings of the 1999, 2000, and 2001 AACC/CAP [American Association for Clinical Chemistry/College of American Pathologists] Immunosuppressive Drugs (CS) Monitoring Survey. MAIN OUTCOME MEASURES: For each drug, total variance was partitioned into specimen, mailing, year, and interlaboratory effects for each analytical method. PARTICIPANTS: The 292 laboratories for cyclosporine and 177 laboratories for tacrolimus enrolled in the survey from 1999 to 2001. RESULTS: For both cyclosporine and tacrolimus, the major source of imprecision came from within-laboratory factors, which accounted for nearly 85% (range, 77% to 90%) of the total variance. For cyclosporine, the major component of within-laboratory variance was between-mailing, within-year effect, whereas for tacrolimus it was the between-year, within-laboratory variation. CONCLUSION: The major source of long-term survey imprecision for cyclosporine and tacrolimus is within-laboratory factors. The finding that 85% of the total variance was due to within-laboratory variation is similar to other therapeutic drugs.

Full Text

Duke Authors

Cited Authors

  • Steele, BW; Wang, E; Soldin, SJ; Klee, G; Elin, RJ; Witte, DL; College of American Pathologists Study,

Published Date

  • March 2003

Published In

Volume / Issue

  • 127 / 3

Start / End Page

  • 283 - 288

PubMed ID

  • 12653570

Electronic International Standard Serial Number (EISSN)

  • 1543-2165

Digital Object Identifier (DOI)

  • 10.5858/2003-127-0283-ALRSOI


  • eng

Conference Location

  • United States