Thyroxine - free (FT4)

Included in meta analysis


Maes M, Mommen K, Hendrickx D, Peeters D, D’Hondt P, Ranjan R, De Meyer F and Scharpé S, 1997, Clin Endocrinol, 46, 587-98 , Components of biological variation, including seasonality, in blood concentrations of TSH, TT3, FT4, PRL, cortisol and testosterone in healthy volunteers


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 B
8. Outlier Analysis C
9. Normality B
10. Variance Homogeneity C
12. CI A
13. No of Results B
14. Concentrations B
15. Total Score C8,10,11

Item Details

Parameter Score
Matrix Serum
Measurand Thyroxine - free (FT4)
Unit pmol / L
Overall Analytical Principle Method Immunoassay; ELISA
Number of Subjects 26
Number of Subjects included in BV estimation 26
Ethinicity Unknown
Age Mean / Median 38.7
Age Min
Age Max
Age SD 13.4
Number of Males 13
Number of Females 13
State of Well Being
Healthy (excl pregnant)
Study Duration Length 1
Study Duration Units Year
Sampling Intervals, e.g. X sample(s) per Interval Unit 1
Interval Units Month
Sampling Times Start Time: 07.30
End Time: 08.30
Number of Samples 12
Average Number of Samples Used for BV Estimation 12.0
Average Number of Replicates 1.0
Estimates of CVi 7.1
Calculated Confidence Intervals of CVi Lower: 2.99, Upper: 8.78
Estimates of CVg 9.1
Calculated Confidence Intervals of CVg Lower: 6.93, Upper: 12.76
Analytical CV 7.5
Calculated Confidence Intervals of Analytical CV Lower: 6.01, Upper: 9.97
Measurand Mean
Measurand Min
Measurand Max
Measurand SD