scholarly journals Pregnancy Week-Specific Reference Ranges for Thyrotropin and Free Thyroxine in the North Denmark Region Pregnancy Cohort

Thyroid ◽  
2019 ◽  
Vol 29 (3) ◽  
pp. 430-438 ◽  
Author(s):  
Stine Linding Andersen ◽  
Stig Andersen ◽  
Allan Carlé ◽  
Peter Astrup Christensen ◽  
Aase Handberg ◽  
...  
Keyword(s):  
Free Thyroxine ◽  
Specific Reference ◽  
Reference Ranges ◽  
Pregnancy Cohort ◽  
The North

Effects of Age and Health on the Euthyroid Reference Ranges for Serum Free Thyroxine and Free Triiodothyronine

1985 ◽  
Vol 24 (02) ◽  
pp. 57-65 ◽  
Author(s):  
J. E. M. Midgley ◽  
K. R. Gruner
Keyword(s):  
Lower Limit ◽  
Healthy Subjects ◽  
Thyroid Dysfunction ◽  
Reference Range ◽  
Free Thyroxine ◽  
Reference Ranges ◽  
Free Triiodothyronine ◽  
Serum Free ◽  
Young Subjects ◽  
Age Range

SummaryAge-related trends in serum free thyroxine (FT4) and free triiodothyronine (FT3) concentrations were measured in 7248 euthyroid subjects (age-range 3 months to 106 years). 5700 were patients referred to hospitals for investigation of suspected thyroid dysfunction, but who were diagnosed euthyroid. 1548 were healthy blood donors (age-range 18-63 years) with no indication of thyroid dysfunction. FT4 concentrations were little affected by the age, the sex or the state of health of the subjects in either group. Serum FT3 concentrations were significantly affected by both age and health factors. The upper limit of the euthyroid reference range for young subjects up to 15 years was about 20% higher (10.4 pmol/1) than for adult subjects older than 25 years (8.8 pmol/1). The change in the upper limits typical of young subjects to that typical of adults occurred steadily over the decade 15–25 years. After this age, little further change occurred, especially in healthy subjects. Additionally, the lower limit of the euthyroid range for FT3 was extended by the inclusion in the reference group of patients referred to hospitals. Compared with the lower limit of the FT3 range for healthy subjects (5 pmol/1), the corresponding limit for referred subjects (young or adult) was 3.5–3.8 pmol/1. Broadening of the FT3 reference range was probably brought about by a significant number of patients in the hospital-referred group with the “1OW-T3 syndrome” of mild non-thyroidal illness. Accordingly, FT3 was inferior to FT4 in the discrimination of hypothyroidism, as FT4 was unaffected by this phenomenon. Effects of age and non-thyroidal illness on serum FT3 concentrations require great care when selecting subjects for a laboratory euthyroid reference range typical of the routine workload. Constraints on the choice of subjects for FT4 reference ranges are less stringent.

scholarly journals A Reference Spectrum Model for Estimating Source Levels of Marine Shipping Based on Automated Identification System Data

2021 ◽  
Vol 9 (4) ◽  
pp. 369 ◽  
Author(s):  
Alexander MacGillivray ◽  
Christ de Jong
Keyword(s):  
Objective Assessment ◽  
Noise Pollution ◽  
Specific Reference ◽  
Identification System ◽  
Reference Spectrum ◽  
Underwater Sound ◽  
The North ◽  
Joint Monitoring ◽  
Source Level ◽  
Spectrum Model

Underwater sound mapping is increasingly being used as a tool for monitoring and managing noise pollution from shipping in the marine environment. Sound maps typically rely on tracking data from the Automated Information System (AIS), but information available from AIS is limited and not easily related to vessel noise emissions. Thus, robust sound mapping tools not only require accurate models for estimating source levels for large numbers of marine vessels, but also an objective assessment of their uncertainties. As part of the Joint Monitoring Programme for Ambient Noise in the North Sea (JOMOPANS) project, a widely used reference spectrum model (RANDI 3.1) was validated against statistics of monopole ship source level measurements from the Vancouver Fraser Port Authority-led Enhancing Cetacean Habitat and Observation (ECHO) Program. These validation comparisons resulted in a new reference spectrum model (the JOMOPANS-ECHO source level model) that retains the power-law dependence on speed and length but incorporates class-specific reference speeds and new spectrum coefficients. The new reference spectrum model calculates the ship source level spectrum, in decidecade bands, as a function of frequency, speed, length, and AIS ship type. The statistical uncertainty (standard deviation of the deviation between model and measurement) in the predicted source level spectra of the new model is estimated to be 6 dB.

Evaluation of Thyroid Function in Pregnant Women Using Automated Immunoassays

2021 ◽  
Author(s):  
K Aaron Geno ◽  
Matthew S Reed ◽  
Mark A Cervinski ◽  
Robert D Nerenz
Keyword(s):  
Pregnant Women ◽  
Equilibrium Dialysis ◽  
Reference Interval ◽  
First Trimester ◽  
Reference Intervals ◽  
Free Thyroxine ◽  
Specific Reference ◽  
Childbearing Age ◽  
Thyroid Autoantibody ◽  
The Impact

Abstract Introduction Automated free thyroxine (FT4) immunoassays are widely available, but professional guidelines discourage their use in pregnant women due to theoretical under-recoveries attributed to increased thyroid hormone binding capacity and instead advocate the use of total T4 (TT4) or free thyroxine index (FTI). The impact of this recommendation on the classification of thyroid status in apparently euthyroid pregnant patients was evaluated. Methods After excluding specimens with thyroid autoantibody concentrations above reference limits, thyroid-stimulating hormone (TSH), FT4, TT4, and T-uptake were measured on the Roche Cobas® platform in remnant clinical specimens from at least 147 nonpregnant women of childbearing age and pregnant women at each trimester. Split-sample comparisons of FT4 as measured by the Cobas and equilibrium dialysis were performed. Results FT4 decreased with advancing gestational age by both immunoassay and equilibrium dialysis. TSH declined during the first trimester, remained constant in the second, and increased throughout the third, peaking just before delivery. Interpretation of TT4 concentrations using 1.5-times the nonpregnant reference interval classified 13.6% of first trimester specimens below the lower reference limit despite TSH concentrations within trimester-specific reference intervals. Five FTI results from 480 pregnant individuals (about 1.0%) fell outside the manufacturer’s reference interval. Conclusions Indirect FT4 immunoassay results interpreted in the context of trimester-specific reference intervals provide a practical and viable alternative to TT4 or FTI. Declining FT4 and increasing TSH concentrations near term suggest that declining FT4 is not an analytical artifact but represents a true physiological change in preparation for labor and delivery.

Breed‐specific reference ranges for standard echocardiographic measurements in salukis

2019 ◽  
Vol 60 (6) ◽  
pp. 374-378 ◽  
Author(s):  
S. Giraut ◽  
J. Häggström ◽  
L. L. E. Koskinen ◽  
H. Lohi ◽  
M. Wiberg
Keyword(s):  
Specific Reference ◽  
Reference Ranges

AGE-SPECIFIC REFERENCE RANGES FOR PROSTATE-SPECIFIC ANTIGEN-BASED DETECTION OF PROSTATE CANCER IN BLACK MEN

1996 ◽  
Vol 89 (Supplement) ◽  
pp. S131
Author(s):  
Ted O. Morgan ◽  
Steven J. Jacobsen ◽  
William F. McCarthy ◽  
David G. McLeod ◽  
Judd W. Moul
Keyword(s):  
Prostate Cancer ◽  
Prostate Specific Antigen ◽  
Black Men ◽  
Specific Antigen ◽  
Specific Reference ◽  
Reference Ranges

scholarly journals Reference Intervals of Thyroid Hormones and Correlation of BMI with Thyroid Function in Healthy Zhuang Ethnic Pregnant Women

2018 ◽  
Vol 2018 ◽  
pp. 1-8 ◽  
Author(s):  
Yonghong Sheng ◽  
Dongping Huang ◽  
Shun Liu ◽  
Xuefeng Guo ◽  
Jiehua Chen ◽  
...  
Keyword(s):  
Thyroid Hormones ◽  
Pregnant Women ◽  
Thyroid Function ◽  
Reference Intervals ◽  
Thyroid Stimulating Hormone ◽  
Specific Reference ◽  
American Thyroid Association ◽  
Reference Ranges ◽  
Free Triiodothyronine ◽  
Cross Sectional

Ethnic differences in the level of thyroid hormones exist among individuals. The American Thyroid Association (ATA) recommends that an institution or region should establish a specific thyroid hormone reference value for each stage of pregnancy. To date, a limited number of studies have reported the level of thyroid hormones in Chinese minorities, and the exact relationship between BMI and thyroid function in pregnant women is ill. This study was performed to establish trimester-specific reference ranges of thyroid hormones in Zhuang ethnic pregnant women and explore the role of body mass index (BMI) on thyroid function. A total of 3324 Zhuang ethnic health pregnant women were recruited in this Zhuang population-based retrospective cross-sectional study. The values of thyroid stimulating hormone (TSH), free thyroxine (FT4), and free triiodothyronine (FT3) were determined by automatic chemiluminescence immunoassay analyzer. Multivariate linear regression and binary logistic regression were constructed to evaluate the influence of BMI on the thyroid function. The established reference intervals for the serum thyroid hormones in three trimesters were as follows: TSH, 0.02–3.28, 0.03–3.22, and 0.08-3.71 mIU/L; FT4, 10.57–19.76, 10.05–19.23, and 8.96–17.75 pmol/L; FT3, 3.51–5.64, 3.42–5.42, and 2.93–5.03 pmol/L. These values were markedly lower than those provided by the manufacturers for nonpregnant adults which can potentially result in 6.10% to 19.73% misclassification in Zhuang pregnant women. Moreover, BMI was positively correlated with isolated hypothyroxinemia (OR=1.081, 95% CI=1.007–1.161), while the correlation between the BMI and subclinical hypothyroidism was not statistically significant (OR=0.991, 95% CI=0.917–1.072). This is the first study focusing on the reference ranges of thyroid hormones in Guangxi Zhuang ethnic pregnant women, which will improve the care of them in the diagnosis and treatment. We also found that high BMI was positively associated with the risk of isolated hypothyroxinemia.

scholarly journals Results of an international round robin for serum and whole-blood folate

1996 ◽  
Vol 42 (10) ◽  
pp. 1689-1694 ◽  
Author(s):  
E W Gunter ◽  
B A Bowman ◽  
S P Caudill ◽  
D B Twite ◽  
M J Adams ◽  
...  
Keyword(s):  
Public Health ◽  
Clinical Data ◽  
Reference Materials ◽  
Whole Blood ◽  
Interlaboratory Comparison ◽  
Round Robin ◽  
Specific Reference ◽  
Reference Ranges ◽  
Comparison Study ◽  
International Round

Abstract Because of the increasing significance of folate nutriture to public health, a "round robin" interlaboratory comparison study was conducted to assess differences among methods. Twenty research laboratories participated in a 3-day analysis of six serum and six whole-blood pools. Overall means, SDs, and CVs derived from these results were compared within and across method types. Results reported for serum and whole-blood folate demonstrated overall CVs of 27.6% and 35.7%, respectively, across pools and two- to ninefold differences in concentrations between methods, with the greatest variation occurring at critical low folate concentrations. Although results for serum pools were less variable than those for whole-blood pools, substantial intermethod variation still occurred. The overall results underscore the urgent need for developing and validating reference methods for serum and whole-blood folate and for properly characterized reference materials. For evaluating study or clinical data, method-specific reference ranges (established with clinical confirmation of values for truly folate-deficient individuals) must be used.

Are age-specific reference ranges for CYFRA 21-1 appropriate?

2018 ◽  
Vol 78 (4) ◽  
pp. 335-336
Author(s):  
Gustav Mikkelsen ◽  
Arne Åsberg ◽  
Gunhild Garmo Hov
Keyword(s):  
Specific Reference ◽  
Reference Ranges

Abstract 1601: Comprehensive Evaluation of the Left Ventricular Systolic and Diastolic Synchronicity in 160 “Completely” Healthy Normal Volunteers Using Tissue Doppler Echocardiography

Circulation ◽  
2007 ◽  
Vol 116 (suppl_16) ◽  
Author(s):  
Hyung-Kwan Kim ◽  
Keun-Ho Park ◽  
Suna-A Chang ◽  
Jin-Shik Park ◽  
Hyun-Jae Kang ◽  
...  
Keyword(s):  
Age Groups ◽  
Mitral Annulus ◽  
Tissue Doppler ◽  
Left Ventricular ◽  
Doppler Imaging ◽  
Cardiac Resynchronization ◽  
Specific Reference ◽  
Reference Ranges ◽  
Normal Ranges ◽  
Mitral Annulus Velocity

Background Growing use of the left ventricular(LV) systolic(LVSIsys) and diastolic synchronicity indexes(LVSIdia) in selecting potential responders to cardiac resynchronization therapy(CRT) has created a need for normative reference values. This study was performed to determine reference ranges for tissue Doppler imaging-derived LVSIsys and LVSIdia, and to assess their relationships to age and conventional parameters reflecting LV systolic and diastolic functions. Methods and Results We recruited 160 completely healthy volunteers (45±13yrs, 104 men) free of any systemic or cardiovascular disease. Maximal difference and SD of time to peak systolic and early diastolic velocities for LVSIsys and LVSIdia were measured using 6- and 12-segment models. Table and Figure represent normal ranges. Aging was not found to significantly change LVSIsys, whereas LVSIdia progressively and consistently increased with age. Significant correlations were observed between LVSIdia and parameters representing LV diastolic function, i.e. early mitral inflow velocity and its deceleration time, and early mitral annulus velocity. A physiologic rise in LV mass/Ht 2.7 showed a weak, but significant correlation with LVSIdia( r = 0.15 to 0.22), but not with LVSIsys. On multivariate analysis, age-dependent increase in LVSIdia was confirmed. Conclusions Age-specific reference ranges for LVSIsys and LVSIdia are presented here. LVSIsys remain stable throughout age groups, whereas LVSIdia progressively increases with age. These data given here will be useful for defining abnormal LV synchronous contraction and relaxation, and help better select patients likely to respond favorably to CRT.

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