scholarly journals Establishment of reference intervals of biochemical analytes for South African adults: a study conducted as part of the IFCC global multicentre study on reference values

2021 ◽  
pp. 8-23
Author(s):  
FC Smit ◽  
K Ichihara ◽  
J George ◽  
E Blanco-Blanco ◽  
M Hoffmann ◽  
...  
Keyword(s):  
South African ◽  
Reference Values ◽  
Clinical Chemistry ◽  
Parametric Method ◽  
Density Lipoprotein ◽  
Reference Intervals ◽  
Mixed Ancestry ◽  
Serum Samples ◽  
Age Related ◽  
Non Parametric

Objective: This study was conducted as a part of the International Federation of Clinical Chemistry and Laboratory Medicine (IFCC) global study for establishing reference intervals (RIs) of common laboratory tests for the South African population considering gender, ethnicity, age and body mass index (BMI). Methods: The researchers recruited 1 143 apparently healthy volunteers aged 18–65: 551 African (Afr) and 592 non-African (NAfr) (comprising 383 Caucasian and 209 Mixed Ancestry). Serum samples were measured for 40 chemistry and immunochemistry analytes. The standard deviation ratio (SDR) guided the need for partitioning reference values according to gender, ethnicity and age using a threshold of ≥ 0.4. The latent abnormal values exclusion (LAVE) method was applied to reduce influences of latent diseases before deriving RIs using both parametric and non-parametric methods. Results: Based on SDRsex, males showed higher albumin, uric acid, creatinine, AST, CK and ferritin. Based on SDRRC, Afr compared to NAfr showed (i) higher total protein, amylase, CRP, immunoglobulin G and A and (ii) lower total bilirubin, total cholesterol, low-density lipoprotein cholesterol (LDL-C), ALT and cholinesterase. Both age-related changes in glucose and LDL-C, and BMI-related changes in ALT, ALP and LDH were more prominent in NAfr. RIs were determined according to gender, age and ethnicity. The LAVE method was effective in lowering the upper RI limits (UL) of nutritional markers such as γGT and CRP. Compared to the non-parametric method, the parametric method gave narrower confidence intervals of ULs for analytes with skewed distributions. Conclusion: Establishing RIs by considering ethnicity was essential in many analytes in South Africa. Age and BMI-related changes differed greatly between Afr and NAfr.

Establishment of reference intervals of clinical chemistry analytes for the adult population in Saudi Arabia: a study conducted as a part of the IFCC global study on reference values

2016 ◽  
Vol 54 (5) ◽  
Author(s):  
Anwar Borai ◽  
Kiyoshi Ichihara ◽  
Abdulaziz Al Masaud ◽  
Waleed Tamimi ◽  
Suhad Bahijri ◽  
...  
Keyword(s):  
Reference Values ◽  
Clinical Chemistry ◽  
Adult Population ◽  
Parametric Method ◽  
Reference Intervals ◽  
Test Results ◽  
Upper Limits ◽  
High Prevalence ◽  
Global Study ◽  
Non Parametric

AbstractBackground:This study is a part of the IFCC-global study to derive reference intervals (RIs) for 28 chemistry analytes in Saudis.Method:Healthy individuals (n=826) aged ≥18 years were recruited using the global study protocol. All specimens were measured using an Architect analyzer. RIs were derived by both parametric and non-parametric methods for comparative purpose. The need for secondary exclusion of reference values based on latent abnormal values exclusion (LAVE) method was examined. The magnitude of variation attributable to gender, ages and regions was calculated by the standard deviation ratio (SDR). Sources of variations: age, BMI, physical exercise and smoking levels were investigated by using the multiple regression analysis.Results:SDRs for gender, age and regional differences were significant for 14, 8 and 2 analytes, respectively. BMI-related changes in test results were noted conspicuously for CRP. For some metabolic related parameters the ranges of RIs by non-parametric method were wider than by the parametric method and RIs derived using the LAVE method were significantly different than those without it. RIs were derived with and without gender partition (BMI, drugs and supplements were considered).Conclusions:RIs applicable to Saudis were established for the majority of chemistry analytes, whereas gender, regional and age RI partitioning was required for some analytes. The elevated upper limits of metabolic analytes reflects the existence of high prevalence of metabolic syndrome in Saudi population.

A multicenter nationwide reference intervals study for common biochemical analytes in Turkey using Abbott analyzers

2014 ◽  
Vol 52 (12) ◽  
Author(s):  
Yesim Ozarda ◽  
Kiyoshi Ichihara ◽  
Diler Aslan ◽  
Hulya Aybek ◽  
Zeki Ari ◽  
...  
Keyword(s):  
Reference Values ◽  
Parametric Method ◽  
Density Lipoprotein ◽  
Hdl Cholesterol ◽  
Turkish Population ◽  
Reference Intervals ◽  
Test Results ◽  
Age Related ◽  
Sources Of Variation ◽  
Exclusion Method

AbstractA nationwide multicenter study was organized to establish reference intervals (RIs) in the Turkish population for 25 commonly tested biochemical analytes and to explore sources of variation in reference values, including regionality.Blood samples were collected nationwide in 28 laboratories from the seven regions (≥400 samples/region, 3066 in all). The sera were collectively analyzed in Uludag University in Bursa using Abbott reagents and analyzer. Reference materials were used for standardization of test results. After secondary exclusion using the latent abnormal values exclusion method, RIs were derived by a parametric method employing the modified Box-Cox formula and compared with the RIs by the non-parametric method. Three-level nested ANOVA was used to evaluate variations among sexes, ages and regions. Associations between test results and age, body mass index (BMI) and region were determined by multiple regression analysis (MRA).By ANOVA, differences of reference values among seven regions were significant in none of the 25 analytes. Significant sex-related and age-related differences were observed for 10 and seven analytes, respectively. MRA revealed BMI-related changes in results for uric acid, glucose, triglycerides, high-density lipoprotein (HDL)-cholesterol, alanine aminotransferase, and γ-glutamyltransferase. Their RIs were thus derived by applying stricter criteria excluding individuals with BMI >28 kg/mWith the lack of regional differences and the well-standardized status of test results, the RIs derived from this nationwide study can be used for the entire Turkish population.

scholarly journals Establishment of Reference Intervals of Clinical Chemistry Analytes for the Adult Population in Egypt

2020 ◽  
Author(s):  
Heba Baz ◽  
Kiyoshi Ichihara ◽  
May Selim ◽  
Ahmed Awad ◽  
Sarah Aglan ◽  
...  
Keyword(s):  
Regional Differences ◽  
Clinical Chemistry ◽  
Adult Population ◽  
Middle Eastern ◽  
Low Density Lipoprotein ◽  
Parametric Method ◽  
Density Lipoprotein ◽  
Reference Intervals ◽  
Lipoprotein Cholesterol ◽  
Multiple Regions

AbstractBackgroundThis is the first Egyptian nationwide study for derivation of reference intervals (RIs) for 34 major chemistry analytes. It was conducted as a part of the global initiative by the IFCC Committee on Reference Intervals and Decision Limits (C-RIDL) for establishing country-specific RIs based on a harmonized protocol.Methods691 apparently healthy volunteers aged ≥18 years were recruited from multiple regions in Egypt. Serum specimens were analyzed in two centers. The harmonization and standardization of test results were achieved by measuring value-assigned serum panel provided by C-RIDL. The RIs were calculated by parametric method. Sources of variation of reference values (RVs) were evaluated by multiple regression analysis. The need for partitioning by sex, age, and region was judged primarily by standard deviation ratio (SDR).ResultsGender-specific RIs were required for six analytes including total bilirubin (TBil), aspartate and alanine aminotransferase (AST, ALT). Seven analytes required age-partitioning including glucose and low-density lipoprotein cholesterol (LDL-C)., Regional differences were observed between northern and southern Egypt for direct bilirubin, glucose, and high-density-lipoprotein cholesterol (HDL-C) with all their RVs lower in southern Egypt. Compared with other collaborating countries, the features of Egyptian RVs were lower HDL-C and TBil and higher TG and C-reactive protein. In addition, BMI showed weak association with most of nutritional markers. These features were shared with two other Middle Eastern countries: Saudi Arabia and Turkey.ConclusionThe standardized RIs established by this study can be used as common Egyptian RI, except for a few analytes that showed regional differences. Despite high prevalence of obesity among Egyptians, their RVs of nutritional markers are less sensitive to increased BMI, compared to other collaborating countries.

scholarly journals Establishment of reference intervals of clinical chemistry analytes for the adult population in Egypt

PLoS ONE ◽  
2021 ◽  
Vol 16 (3) ◽  
pp. e0236772
Author(s):  
Heba Baz ◽  
Kiyoshi Ichihara ◽  
May Selim ◽  
Ahmed Awad ◽  
Sarah Aglan ◽  
...  
Keyword(s):  
Regional Differences ◽  
Clinical Chemistry ◽  
Adult Population ◽  
Middle Eastern ◽  
Low Density Lipoprotein ◽  
Parametric Method ◽  
Density Lipoprotein ◽  
Reference Intervals ◽  
Lipoprotein Cholesterol ◽  
Multiple Regions

Background This is the first Egyptian nationwide study for derivation of reference intervals (RIs) for 34 major chemistry analytes. It was conducted as a part of the global initiative by the IFCC Committee on Reference Intervals and Decision Limits (C-RIDL) for establishing country-specific RIs based on a harmonized protocol. Methods 691 apparently healthy volunteers aged ≥18 years were recruited from multiple regions in Egypt. Serum specimens were analyzed in two centers. The harmonization and standardization of test results were achieved by measuring value-assigned serum panel provided by C-RIDL. The RIs were calculated by parametric method. Sources of variation of reference values (RVs) were evaluated by multiple regression analysis. The need for partitioning by sex, age, and region was judged primarily by standard deviation ratio (SDR). Results Gender-specific RIs were required for six analytes including total bilirubin (TBil), aspartate and alanine aminotransferase (AST, ALT). Seven analytes required age-partitioning including glucose and low-density lipoprotein cholesterol (LDL-C). Regional differences were observed between northern and southern Egypt for direct bilirubin, glucose, and high-density-lipoprotein cholesterol (HDL-C) with all their RVs lower in southern Egypt. Compared with other collaborating countries, the features of Egyptian RVs were lower HDL-C and TBil and higher TG and C-reactive protein. In addition, BMI showed weak association with most of nutritional markers. These features were shared with two other Middle Eastern countries: Saudi Arabia and Turkey. Conclusion The standardized RIs established by this study can be used as common Egyptian RI, except for a few analytes that showed regional differences. Despite high prevalence of obesity among Egyptians, their RVs of nutritional markers are less sensitive to increased BMI, compared to other collaborating countries.

scholarly journals Early pregnancy reference intervals; 29 serum analytes from 4 to 12 weeks’ gestation in naturally conceived and uncomplicated pregnancies resulting in live births

2019 ◽  
Vol 57 (12) ◽  
pp. 1956-1967 ◽  
Author(s):  
Jesper Friis Petersen ◽  
Lennart J. Friis-Hansen ◽  
Andreas Kryger Jensen ◽  
Anders Nyboe Andersen ◽  
Ellen C.L. Løkkegaard
Keyword(s):  
Pregnant Women ◽  
Early Pregnancy ◽  
Clinical Chemistry ◽  
Clinical Care ◽  
Local Population ◽  
First Trimester ◽  
Reference Intervals ◽  
Specific Reference ◽  
Cancer Antigen 125 ◽  
Serum Samples

Abstract Background Pregnancy introduces major physiological changes that also alter biochemical analytes. Maternal and perinatal health can be optimized by early intervention and therefore, pregnancy-specific reference intervals (RIs) for the local population are warranted. While the second and third trimester-specific changes are well described, the first trimester is less well characterized. We therefore wanted to facilitate early detection of abnormalities by generating first trimester reference values for 29 common analytes. Methods In a prospective early pregnancy (PEP) cohort (2016–2017), 203 pregnant women were recruited from 4 to 8 weeks’ gestation. Consecutive blood samples were drawn every 2 weeks until an ongoing second trimester pregnancy (n = 164) or a miscarriage (n = 39) occurred. After exclusion of women with complicated pregnancies or deliveries (n = 42), 122 women were included. The serum samples collected at <6, 6–8, 8–10, 10–12 and >12 weeks’ gestation were analyzed for 29 common analytes. Subsequently the RIs were calculated according to the International Federation of Clinical Chemistry and Laboratory Medicine (IFCC) recommendations (2.5–97.5th percentiles) and compared with the conventional RIs for non-pregnant women. Results Human chorionic gonadotropin (hCG), progesterone (P4), estradiol (E2), pregnancy-associated plasma protein A (PAPP-A), cancer antigen 125 (CA125), thyroid stimulating hormone (TSH), creatinine (CREA) and albumin (ALB) showed an early pregnancy-dependent change compared with conventional limits. For ALB the change was seen at 5.5 weeks’ gestation. Conclusions We report gestational age-specific RIs available from the early part of the first trimester applicable to everyday clinical care of pregnant women. Well-known alterations of RIs seen in later trimesters are also observed in the first.

scholarly journals Reference intervals for selected serum biochemistry analytes in cheetahs (Acinonyx jubatus)

2016 ◽  
Vol 87 (1) ◽  
Author(s):  
Gavin C. Hudson-Lamb ◽  
Johan P. Schoeman ◽  
Emma H. Hooijberg ◽  
Sonja K. Heinrich ◽  
Adrian S.W. Tordiffe
Keyword(s):  
Bootstrap Method ◽  
Parametric Method ◽  
Serum Biochemistry ◽  
Reference Intervals ◽  
Dietary Factors ◽  
Future Health ◽  
Baseline Serum ◽  
Acinonyx Jubatus ◽  
Free Ranging ◽  
Non Parametric

Published haematologic and serum biochemistry reference intervals are very scarce for captive cheetahs and even more for free-ranging cheetahs. The current study was performed to establish reference intervals for selected serum biochemistry analytes in cheetahs. Baseline serum biochemistry analytes were analysed from 66 healthy Namibian cheetahs. Samples were collected from 30 captive cheetahs at the AfriCat Foundation and 36 free-ranging cheetahs from central Namibia. The effects of captivity-status, age, sex and haemolysis score on the tested serum analytes were investigated. The biochemistry analytes that were measured were sodium, potassium, magnesium, chloride, urea and creatinine. The 90% confidence interval of the reference limits was obtained using the non-parametric bootstrap method. Reference intervals were preferentially determined by the non-parametric method and were as follows: sodium (128 mmol/L – 166 mmol/L), potassium (3.9 mmol/L – 5.2 mmol/L), magnesium (0.8 mmol/L – 1.2 mmol/L), chloride (97 mmol/L – 130 mmol/L), urea (8.2 mmol/L – 25.1 mmol/L) and creatinine (88 µmol/L – 288 µmol/L). Reference intervals from the current study were compared with International Species Information System values for cheetahs and found to be narrower. Moreover, age, sex and haemolysis score had no significant effect on the serum analytes in this study. Separate reference intervals for captive and free-ranging cheetahs were also determined. Captive cheetahs had higher urea values, most likely due to dietary factors. This study is the first to establish reference intervals for serum biochemistry analytes in cheetahs according to international guidelines. These results can be used for future health and disease assessments in both captive and free-ranging cheetahs.

scholarly journals Reference Intervals (RIs) of Lipid Parameters for Nepalese Population

2018 ◽  
Vol 6 (4) ◽  
pp. 366-372
Author(s):  
R.V. Mahato ◽  
R.K. Singh ◽  
A. M. Dutta ◽  
K. Ichihara ◽  
M. Lamsal
Keyword(s):  
Total Cholesterol ◽  
Reference Values ◽  
Clinical Laboratory ◽  
Local Population ◽  
Density Lipoprotein ◽  
Physical Exertion ◽  
Hdl Cholesterol ◽  
Reference Interval ◽  
Reference Intervals ◽  
Lipoprotein Cholesterol

Introduction: Reference interval (RIs) is the range of values provided by laboratory scientists in a convenient and practical form to support clinician in interpreting observed values for diagnosis, treatment and monitoring of a disease. Laboratories in Nepal uses RIs, provided in the kit inserts by the manufacturers or from the scientific literature, established for western/European population. It is well known that population across the globe differs physiologically, genetically; race, ethnically, lifestyle, food habits and diet which have great impact on the reference values. Thus, it is inappropriate to use RIs that do not represent the local population. This approach highlights for establishing reference values in Nepalese population using the IFCC-CRIDL guidelines published in (C28-A3). Objectives: The objective of this study is to analyze blood lipids concentration in apparently healthy Nepalese population to set up reference values for total cholesterol (TC), triglycerides (TG), High Density Lipoprotein-cholesterol (HDL-C) and Low Density Lipoprotein-cholesterol (LDL-C) and compare with the internationally recommended values. Methods: Reference individuals selected from healthy volunteers according to the IFCC/C-RIDL protocol in (C28 –A3). Volunteers were requested to avoid excessive physical exertion/exercise/excessive eating and drinking and fast overnight for 10-12 hour. Blood samples were collected from 120 subjects from each five centers of the country between 7:00-10:00 am, serum were separated and refrigerated at -20 in a cryo-vials. Finally, 617 samples were transported to Yamaguchi University, Graduate School of Medicine, Ube, Japan for analysis in dry Ice and 30 parameters were measured by fully automated biochemistry analyzer, Beckman Coulter (BC480) in the clinical laboratory. Results: A reference interval for each parameter was calculated from the 95% reference intervals ranging from 2.5% and 97.5% percentiles and, arithmetic mean + 2 SD were also calculated. The 95% reference range for total cholesterol (2.53-6.14), triglyceride was(0.42-3.32),for HDL Cholesterol was (0.28-1.46), for LDL was(1.05-4.00) and for VLDL was (0.054-0.92) for Nepalese population. Conclusion: Nepalese clinicians can take into consideration of reference lipid values of this study for diagnosis, treatment and monitoring of disease. Int. J. Appl. Sci. Biotechnol. Vol 6(4): 366-372

scholarly journals Reference intervals for 33 biochemical analytes in healthy Indian population: C-RIDL IFCC initiative

2018 ◽  
Vol 56 (12) ◽  
pp. 2093-2103 ◽  
Author(s):  
Swarup A.V. Shah ◽  
Kiyoshi Ichihara ◽  
Alpa J. Dherai ◽  
Tester F. Ashavaid
Keyword(s):  
Parametric Method ◽  
Reference Intervals ◽  
Specific Reference ◽  
Appreciable Effect ◽  
Test Results ◽  
Gender And Age ◽  
Sources Of Variation ◽  
Overnight Fasting ◽  
Nested Analysis ◽  
Non Parametric

Abstract Background In 2011, the IFCC Committee on Reference Intervals and Decision Limits (C-RIDL) initiated a worldwide multicenter study on references values facilitating the implementation of country-specific reference intervals (RIs). There has been no well-designed RI study in India. This study aims to derive RIs for 33 major biochemical analytes in carefully selected healthy Indians as defined in C-RIDL protocol. Methods A total of 512 healthy Indians were recruited. Sera collected from overnight fasting blood samples were measured collectively for the analytes. Multiple regression analysis (MRA) and nested analysis of variance (ANOVA) were used to identify the potential sources of variation (SV) of test results. RI were derived by both parametric and non-parametric methods for comparison. The need for secondary exclusion by latent abnormal values exclusion (LAVE) method was examined. Results MRA results indicated that both age and BMI were apparent SV for many analytes in both sexes. ANOVA revealed that partition of RIs by gender and age was required for 17 analytes (TC, HDL-C, TG, hsCRP, ALB, AST, ALT, ALP, GGT, TBil, Urea, CRE, UA, Fe, TTR, CK and IgM) and 5 (Glu, ALB, TC, ALP and Urea), respectively. RIs by parametric method were generally narrower than by non-parametric method, reflecting distorted peripheral distributions of test results. The LAVE method had no appreciable effect on RIs possibly due to inconsistency among abnormal values of related analytes. Conclusions This study has for the first time provided comprehensive RIs information in healthy Indians. The final RIs adopted were those derived by parametric method without LAVE procedure.

scholarly journals Sources of variation and establishment of Russian reference intervals for major hormones and tumor markers

2020 ◽  
Author(s):  
Anna Ruzhanskaya ◽  
Kiyoshi Ichihara ◽  
Svetlana Evgina ◽  
Irina Skibo ◽  
Nina Vybornova ◽  
...  
Keyword(s):  
Tumor Markers ◽  
Sex Hormones ◽  
Parametric Method ◽  
Bimodal Distribution ◽  
Reference Intervals ◽  
Careful Consideration ◽  
Russian Population ◽  
Serum Samples ◽  
Female Sex Hormones ◽  
Sources Of Variation

AbstractObjectivesA multicenter study was organized to explore sources of variation (SVs) of reference values (RVs) for 24 major immunochemistry analytes and to determine reference intervals (RIs) for the Russian population.MethodsAccording to IFCC Committee on Reference Intervals and Decision Limits (C-RIDL) protocol, 793 healthy volunteers were recruited in St. Petersburg, Moscow, and Yekaterinburg. Serum samples were tested for five tumor markers, 19 hormones and related tests by Beckman Coulter’s UniCel DxI 800 immunochemistry analyzer. SVs were explored using multiple regression analysis and ANOVA. Standard deviation ratio (SDR) of 0.4 was used as primary guide for partitioning RIs by gender and age.ResultsSDR for between-city difference was <0.4 for all analytes. Secondary exclusion of individuals was done under the following conditions: for female sex-hormones, those with contraceptives (8%); for CA19-9, those supposed to have negative Lewis blood-group (10.5%); for insulin, those with BMI≥28 kg/m2 (29.9%); for the thyroid panel, those with anti-thyroid antibodies (10.3% in males; 24.5% in females). Gender-specific RIs were required for all analytes except CA19-9, CA15-3, thyroid-related tests, parathyroid hormone, and insulin. Age-specific RIs were required for α-fetoprotein and all sex-hormones except testosterone. RIs were generally derived by parametric method after Gaussian transformation using modified Box-Cox formula. Exceptions were growth hormone, estradiol, and progesterone, for which nonparametric method was required due to bimodal distribution and/or insufficient detection limit.ConclusionRIs for major hormones and tumor markers specific for the Russian population were derived based on the up-to-date internationally harmonized protocol by careful consideration of analyte-specific SVs.

Paediatric reference intervals for 17 Roche cobas 8000 e602 immunoassays in the CALIPER cohort of healthy children and adolescents

2019 ◽  
Vol 57 (12) ◽  
pp. 1968-1979 ◽  
Author(s):  
Mary Kathryn Bohn ◽  
Victoria Higgins ◽  
Shervin Asgari ◽  
Felix Leung ◽  
Barry Hoffman ◽  
...  
Keyword(s):  
Children And Adolescents ◽  
Reference Values ◽  
Laboratory Tests ◽  
Clinical Decision Making ◽  
Reference Intervals ◽  
Healthy Children ◽  
Serum Samples ◽  
Clinical Laboratories ◽  
Age And Sex ◽  
Roche Cobas

Abstract Background The diagnostic utility of laboratory tests in paediatric medicine relies heavily on the availability of appropriate reference intervals (RIs). The Canadian Laboratory Initiative on Paediatric Reference Intervals (CALIPER) has established a comprehensive database of covariate-stratified RIs for many paediatric laboratory tests using a large, healthy reference population. Several automated analysers in widespread use in clinical laboratories have already been studied. Here, we extend the testing to Roche immunoassays and report, for the first time, comprehensive paediatric RIs for 17 endocrine and special chemistry markers. Methods A total of 741 healthy children and adolescents (1 day to <19 years) were recruited and serum samples were analysed for 17 immunoassays on the Roche cobas 8000 e602 Immunoassay Analyzer. Age and sex-specific RIs were established and corresponding 90% confidence intervals (CIs) were calculated in accordance with Clinical and Laboratory Standards Institute guidelines. Results Reference values for all analytes measured required age partitioning, particularly during early life and throughout adolescence. Of the 17 analytes measured, eight required sex partitioning, including ferritin, thyroid stimulating hormone (TSH), total triiodothyronine (TT3) and all fertility/sex hormones, except prolactin. Conclusions This is the first study to determine accurate paediatric RIs for Roche immunoassays. RIs were generally similar to those previously published by CALIPER on other analytical platforms, highlighting the reproducibility of age- and sex-specific trends in reference values observed across the paediatric age range. The RIs established in this study will improve the accuracy of test result interpretation and clinical decision-making in clinical laboratories utilising Roche immunoassays.

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