C-terminal cross-linked telopeptide of type I collagen (CTX)


Nguyen TV, Nelson AE, Howe CJ, Seibel MJ, Baxter RC, Handelsman DJ, Kazlauskas R and Ho KK, 2008, Clin Chem, 54, 1268-76 , Within-subject variability and analyticaI imprecision of Insulinlike growth factor axis and collagen markers: implications for clinical diagnosis and doping tests


Total Score


Parameter Score
1. Scale A
2. Study Population A
3. Samples A
4. Measurand A
5. Pre-Analytical A
6. Replicate Analysis B
7. Steady State A
8. Outlier Analysis C
9. Normality A
10. Variance Homogeneity A
12. CI A
13. No of Results C
14. Concentrations A
15. Total Score C8,13

Item Details

Parameter Score
Matrix Serum
Measurand C-terminal cross-linked telopeptide of type I collagen (CTX)
Unit ug / L
Overall Analytical Principle Method Immunoassay; RIA
Number of Subjects 1103
Number of Subjects included in BV estimation 1103
Ethinicity Mixed
Age Mean / Median 22.5
Age Min
Age Max
Age SD
Number of Males 699
Number of Females 404
State of Well Being
Healthy (excl pregnant)
Study Duration Length 3
Study Duration Units Week
Sampling Intervals, e.g. X sample(s) per Interval Unit 3
Interval Units Week
Sampling Times Start Time:
End Time:
Number of Samples 9
Average Number of Samples Used for BV Estimation 3.0
Average Number of Replicates 1.0
Estimates of CVi 12.8
Calculated Confidence Intervals of CVi Lower: 9.14, Upper: 15.65
Estimates of CVg
Calculated Confidence Intervals of CVg Lower: 0.00, Upper:
Analytical CV 3.0
Calculated Confidence Intervals of Analytical CV Lower: 2.79, Upper: 3.25
Measurand Mean 6.2
Measurand Min
Measurand Max
Measurand SD