Age dependence of within-subject biological variation of nine common clinical chemistry analytes
-
Anna Carobene
, Maria Stella Graziani
Abstract
Background: The knowledge of biological variation (BV) data is important for clinical decisions and as a basis for defining analytical quality specifications. However, in gene\xadrating reliable data of biological variation there are still some unsolved problems, such as age dependence. The aim of our work is to verify this aspect.
Methods: Twenty-six subjects divided into three groups by age were studied. Blood samples were collected in lithium heparin tubes for four weeks at one week intervals, on the same day of the week (Tuesday) and at the same time of day (8–9 a.m.) by the same phlebotomist. They were analysed in duplicate for creatinine, urate, calcium, albumin, total cholesterol, high density lipoprotein (HDL) and low density lipoprotein (LDL)-cholesterol, triglycerides and iron. After outlier exclusion by Cochran\u2019s test, components of biological variation were calculated by ANOVA. The significance of the differences between results of the classes was also calculated with the Student\u2019s test (t-test) and the Fisher\u2019s test (F-test).
Results: Excluding albumin, the group 3 results (age range from 78 to 98 years) showed significantly lower CV within subjects (CVW) than the other two groups.
Conclusions: Our data seem to highlight the relevance of the age when choosing the reference subjects for biological variation studies. The level of within-subject biological variation of the elderly group may have been further reduced by the homogeneity of the group constituted by individuals living together in the same nursing home.
©2012 by Walter de Gruyter Berlin Boston
Artikel in diesem Heft
- Masthead
- Masthead
- Editorials
- Reference values and the journal: why the past is now present
- Other-than-annual variations in morning determinations of uric acid
- Reviews
- Blood biochemical markers of bone turnover: pre-analytical and technical aspects of sample collection and handling
- A comprehensive review of upper reference limits reported for (high-)sensitivity cardiac troponin assays: the challenges that lie ahead
- Mini Review
- Reference change values
- Opinion Papers
- Obtaining reference intervals traceable to reference measurement systems: is it possible, who is responsible, what is the strategy?
- Analytical performance, reference values and decision limits. A need to differentiate between reference intervals and decision limits and to define analytical quality specifications
- A pragmatic proposal for permissible limits in external quality assessment schemes with a compromise between biological variation and the state of the art
- Original Articles
- Age dependence of within-subject biological variation of nine common clinical chemistry analytes
- Population-based pediatric reference intervals for general clinical chemistry analytes on the Abbott Architect ci8200 instrument
- Uric acid biorhythm, a feature of long-term variation in a clinical laboratory database
- Age-related changes in serum amino acids concentrations in healthy individuals
- Characterisation of a highly sensitive troponin I assay and its application to a cardio-healthy population
- Are the currently used reference intervals for creatine kinase (CK) reflecting the general population? The Tromsø Study
- Age-specific thyroid hormone and thyrotropin reference intervals for a pediatric and adolescent population
- Serum thyroglobulin reference values according to NACB criteria in healthy subjects with normal thyroid ultrasound
- Thyroid volume influences serum calcitonin levels in a thyroid-healthy population: results of a 3-assay, 519 subjects study
- Impact of the reference values on the clinically-relevant cut-offs. The example of cortisol testing in children
- Trimester-specific reference intervals for haemoglobin A1c (HbA1c) in pregnancy
- The concentration of adiponectin in breast milk is related to maternal hormonal and inflammatory status during 6 months of lactation
- Age- and sex-specific reference limits for creatinine, cystatin C and the estimated glomerular filtration rate
- Determination of the biological variation of S100β and lactate dehydrogenase in disease-free patients with malignant melanoma
- Reference intervals and biological variation for kallikrein 6: influence of age and renal failure
- Faecal haemoglobin concentrations by gender and age: implications for population-based screening for colorectal cancer
- Reference intervals of extended erythrocyte and reticulocyte parameters
- Haematological and iron metabolism parameters in professional cyclists during the Giro d’Italia 3-weeks stage race
- Reference change values for lens culinaris agglutinin-reactive α-fetoprotein and des-γ-carboxy prothrombin in patients with chronic hepatitis C
- Letters to the Editor
- Disadvantages of using biological variation data for reference change values
- Reference change values may need some improvement but are invaluable tools in laboratory medicine
- Insulin-like growth factor 1 reference intervals for a chemiluminescent enzyme immunometric assay (Immulite 2000®) in an adult Mediterranean population
- Reference values for new red blood cell and platelet parameters on the Abbott Diagnostics Cell-Dyn Sapphire
- Congress Abstracts
- Swiss MedLab 2012 Congress of the Swiss Union of Laboratory Medicine (SULM)
Artikel in diesem Heft
- Masthead
- Masthead
- Editorials
- Reference values and the journal: why the past is now present
- Other-than-annual variations in morning determinations of uric acid
- Reviews
- Blood biochemical markers of bone turnover: pre-analytical and technical aspects of sample collection and handling
- A comprehensive review of upper reference limits reported for (high-)sensitivity cardiac troponin assays: the challenges that lie ahead
- Mini Review
- Reference change values
- Opinion Papers
- Obtaining reference intervals traceable to reference measurement systems: is it possible, who is responsible, what is the strategy?
- Analytical performance, reference values and decision limits. A need to differentiate between reference intervals and decision limits and to define analytical quality specifications
- A pragmatic proposal for permissible limits in external quality assessment schemes with a compromise between biological variation and the state of the art
- Original Articles
- Age dependence of within-subject biological variation of nine common clinical chemistry analytes
- Population-based pediatric reference intervals for general clinical chemistry analytes on the Abbott Architect ci8200 instrument
- Uric acid biorhythm, a feature of long-term variation in a clinical laboratory database
- Age-related changes in serum amino acids concentrations in healthy individuals
- Characterisation of a highly sensitive troponin I assay and its application to a cardio-healthy population
- Are the currently used reference intervals for creatine kinase (CK) reflecting the general population? The Tromsø Study
- Age-specific thyroid hormone and thyrotropin reference intervals for a pediatric and adolescent population
- Serum thyroglobulin reference values according to NACB criteria in healthy subjects with normal thyroid ultrasound
- Thyroid volume influences serum calcitonin levels in a thyroid-healthy population: results of a 3-assay, 519 subjects study
- Impact of the reference values on the clinically-relevant cut-offs. The example of cortisol testing in children
- Trimester-specific reference intervals for haemoglobin A1c (HbA1c) in pregnancy
- The concentration of adiponectin in breast milk is related to maternal hormonal and inflammatory status during 6 months of lactation
- Age- and sex-specific reference limits for creatinine, cystatin C and the estimated glomerular filtration rate
- Determination of the biological variation of S100β and lactate dehydrogenase in disease-free patients with malignant melanoma
- Reference intervals and biological variation for kallikrein 6: influence of age and renal failure
- Faecal haemoglobin concentrations by gender and age: implications for population-based screening for colorectal cancer
- Reference intervals of extended erythrocyte and reticulocyte parameters
- Haematological and iron metabolism parameters in professional cyclists during the Giro d’Italia 3-weeks stage race
- Reference change values for lens culinaris agglutinin-reactive α-fetoprotein and des-γ-carboxy prothrombin in patients with chronic hepatitis C
- Letters to the Editor
- Disadvantages of using biological variation data for reference change values
- Reference change values may need some improvement but are invaluable tools in laboratory medicine
- Insulin-like growth factor 1 reference intervals for a chemiluminescent enzyme immunometric assay (Immulite 2000®) in an adult Mediterranean population
- Reference values for new red blood cell and platelet parameters on the Abbott Diagnostics Cell-Dyn Sapphire
- Congress Abstracts
- Swiss MedLab 2012 Congress of the Swiss Union of Laboratory Medicine (SULM)