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PubMed2004

Canine and feline hematology reference values for the ADVIA 120 hematology system.

BACKGROUND: The ADVIA 120 is a laser-based hematology analyzer with software applications for animal species. Accurate reference values would be useful for the assessment of new hematologic parameters and for interlaboratory comparisons. OBJECTIVE: The goal of this study was to establish reference intervals for CBC results and new parameters for RBC morphology, reticulocytes, and platelets in healthy dogs and cats using the ADVIA 120 hematology system. METHODS: The ADVIA 120, with multispecies software (version 1.107-MS), was used to analyze whole blood samples from clinically healthy dogs (n=46) and cats (n=61). Data distribution was determined and reference intervals were calculated as 2.5 to 97.5 percentiles and 25 to 75 percentiles. RESULTS: Most data showed Gaussian or log-normal distribution. The numbers of RBCs falling outside the normocytic-normochromic range were slightly higher in cats than in dogs. Both dogs and cats had reticulocytes with low, medium, and high absorbance. Mean numbers of large platelets and platelet clumps were higher in cats compared with dogs. CONCLUSIONS: Reference intervals obtained on the ADVIA 120 provide valuable baseline information for assessing new hematologic parameters and for interlaboratory comparisons. Differences compared with previously published reference values can be attributed largely to differences in methodology.

Animals↗

PubMed1994

[Reference values for vitamin B12 in blood in a population of children and one of adults using the IMxRB12 method].

UNLABELLED: In this study we have performed the reference values of vitamin B12 of a population of 124 children aged 0-18 years and 42 adults aged 19-55 years, assessed by the recent method IMxR B12. Abbott. The population studied included outpatients, some inpatients and groups of subjects undergoing banal examinations in the Hospital Universitario Materno-Infantil of Barcelona. STATISTICS: Data were first tested for goodness-of-fit gaussian distribution by a nonparametric test, by testing skewness and kurtosis coefficients for significance and by Kolmogorov-Smirnov test. The correlation with the age groups was evaluated with Student's-t-test. RESULTS: We show the histograms of the data obtained and a nonparametric approach selecting the central 95th percentile range. Reference limits (5-95th percentile range) were as follows: Premature infants = 365-1568 ng/L; 1-3 years = 345-1154 ng/L; 4-6 years = 330-1236 ng/L; 7-11 years = 312-1237 ng/L; 12-18 years = 328-1185 ng/L; Adults (19-55 years) = 300-964 ng/L. There were no significant differences between both sexes. The goodness-of-fit test for a gaussian distribution showed no departure from normality except for the groups of children 12-18 years old. A simple linear regression analysis showed that age significantly affected the concentration in inverse way. CONCLUSIONS: The importance of establishing the reference values of vitamin B12 lies in the relevance of this serum analyte to some pathophysiological conditions. Considerable racial heterogeneity exists in populations, and these racial differences profoundly affect total values of vitamin B12 so that different racial reference limits have been suggested.

Adolescent↗

PubMed2001

Reference values of ventilatory variables for healthy adolescents aged 15-19 years.

The main goal of this investigation was the formation of the reference values of ventilatory variables for group of adolescents of both sexes at the age between 15 and 19 years, what was done for the first time for the region of Vojvodina. These values are important in evaluation of respiratory data obtained from patients in the everyday routine examinations. The investigation was carried out on 1151 healthy school children--nonsmokers having the same ethnic origin from the region of Vojvodina. There were 567 males and 584 female participants. Vitalograph dry spirometer (Vitalograph Ltd, Moreton House, Buckingham, England) was used in these examinations. The whole procedure was explained and demonstrated to the participants and best results of their consecutive attempts were taken for further statistical analysis, ie., for calculations of the mean, SD, SEM, coefficient of variation and linear regression. All tests were performed in the morning hours between 8-12 a.m. The results obtained served for calculating the reference values of forced vital capacity (FVC), volume expired in first second of FVC (FEV1.0) and forced midexpiratory flow (FMF). A positive correlation between the respiratory variables and the body height values was found in all groups of participants. The equations of the linear regression related to the ventilatory variables and the height (in 5 cm intervals) were formed separately for both genders. Analysis of the data shows significant differences of the values for all respiratory variables between males and females, which increased with the increasing height of the person. The values for the male group were always higher. In taller volunteers the difference between the sexes becomes even statistically significant, what points that it is necessary to calculate the equations for each gender separately.

Adolescent↗

PubMed2003

Reference values of ductus venosus blood flow velocities and waveform indices from 10 to 20 weeks of gestation.

OBJECTIVE: Our objective was to establish reference values for ductus venosus flow velocities during ventricular systole (S wave) and diastole (D wave), the lowest forward velocity during atrial contraction (A wave) and different calculated indices [(S-A)/D), (S-A)/Vmean, (S-A)/S, S/A, S/D)]. METHODS: Ductus venosus flow velocity waveforms were obtained from 329 singleton pregnancies at 10-20 weeks of gestation by pulsed-wave color Doppler. Reference values were constructed by means of a quadratic regression model after logarithmic transformation of original data. RESULTS: A significant increase in blood flow velocity during atrial contraction [A-wave, (3.5 cm/s to 9.9 cm/s and 12.9 cm/s to 66.3 cm/s respectively, 5-95% centile)], during ventricular systole [S-wave, (19.2 cm/s to 30.1 cm/s and 45.1 cm/s to 84.9 cm/s respectively, 5-95% centile)] and during early ventricular diastole [D-wave, (15.7 cm/s to 26.1 cm/s and 37.9 cm/s to 77.9 cm/s respectively, 5-95% centile)]. The venous indices values decreased with increasing gestational age. In 3 of 329 fetuses (0.91%) a reversed flow during atrial contraction was seen. CONCLUSION: Assessment of ductus venosus blood flow velocities during first and second trimester is feasible by means of color Doppler flow. The reference ranges and calculated velocities established in this study may be utilized in studies dealing with the role of ductus venosus blood flow in chromosomal abnormal fetuses, fetuses with congenital heart disease or fetal myocardial insufficiency of hypoxic origin.

Adolescent↗

PubMed1991

[Characteristics of the distribution and reference values of 12 biochemical indices of the blood serum].

Twelve blood serum parameters: sodium, potassium, chlorine, total protein, cholesterol, glucose, urea nitrogen, creatinine, bilirubin, alkaline phosphatase, alanine and aspartate aminotransferases activities were measured in 488 normal subjects (male), residents of Leningrad, by the Technicon (USA) microanalyzer. Relationships between the estimated reference values and the distribution patterns of the referent blood parameters (variability, symmetric pattern) were analyzed. The authors compare the reference values of the Leningrad population with those obtained by this microanalyzer in the USA.

Blood Chemical Analysis↗

PubMed1998

Reference values for pulse oximetry at high altitude.

OBJECTIVE: To determine reference values for oxygen saturation (Sao2) in healthy children younger than 5 years living at high altitude. DESIGN: One hundred and sixty eight children were examined for Sao2 at 4018 m during well child visits. Physiological state was also noted during the examination. RESULTS: The mean Sao2 was 87.3% (95% confidence intervals (CI) 86.7%, 87.9%) with a median value of 87.7%. A significant difference was observed in Sao2 between children younger than 1 year compared with older children, although the difference was no longer demonstrable when sleeping children were excluded. CONCLUSIONS: This study has provided a reference range of Sao2 values for healthy children under 5 years old so that pulse oximetry may be used as an adjunct in diagnosing acute respiratory infections. Younger children were also shown to have a lower mean Sao2 than older children living at high altitude, which suggests physiological adaptation to high altitude over time. In addition, sleep had a lowering effect on Sao2, although the clinical importance of this remains undetermined.

Aging↗

PubMed2004

Evaluation of the ventricular system in children using transcranial ultrasound: reference values for routine diagnostics.

In children, evaluation of the size of the ventricular system is important. Transcranial Doppler sonography (TCD), a broadly available and easily applicable method that is not hampered by side effects, such as radiation, is a valuable tool for routine examinations. However, standard TCD values of the ventricular system are lacking. In this study, we performed TCD through the temporal acoustic bone window in a large cohort of 1693 healthy children. Of these, 157 had to be excluded because of insufficient bone windows. In the remaining children, a mean width of 1.4 +/- 0.8 mm for the third ventricle, 14.4 +/- 0.8 mm for the right and 14.6 +/- 0.7 mm for the left cella media, and 1.6 +/- 0.7 mm for the right and 1.9 +/- 0.8 mm for the left temporal horn were measured. Side differences are indicated and values are given in relation to age and gender. Inter-rater reproducibility obtained in 25 children was adequate, with no significant difference between the two measurements in any of the parts of the ventricular system measured, rendering these values suitable for reference.

Adolescent↗

PubMed2004

European reference values for Doppler indices of left ventricular diastolic filling.

The European Study Group on diastolic heart failure requires objective evidence of abnormal left ventricular diastolic function to establish the diagnosis of diastolic heart failure, which is common in older people. Reference values for Doppler indices of transmitral flow, used to assess left ventricular diastolic function, have not been reported for people 70 years and over in Europe. The aim of this study was to establish reference values for these Doppler indices of transmitral flow in older people. A random sample of 355 subjects aged 70 and over, living in the community underwent clinical assessment and echocardiography. Asymptomatic subjects with no cardiovascular disease and cardiovascular risk factors were identified. Measurements of five commonly used Doppler indices of transmitral flow from these subjects were obtained and reference range expressed as mean+/-2 standard deviations and as percentiles. We have therefore generated reference Doppler values of transmitral flow for people aged over 70 in a British population.

Age Factors↗

PubMed1987

[Antithrombin III determination in horses. Reference values and acquired antithrombin III deficiency].

Antithrombin III (AT III) determinations were done in healthy and sick horses using the chromogenic substrate Chromozym TH. Reference values for adult horses at 25 degrees C were 18-25 IU AT III per ml plasma and 84-118% AT III activity of normal horse plasma, respectively. Precision and accuracy were good (intra assay coefficient of variation less than 2%, accuracy 10%). Surgical operations on healthy horses led to a biphasic decrease in AT III activity touching the lower border of the reference values on the second postoperative day. Other reasons for acquired AT III deficiencies included disseminated intravascular coagulation (DIC), liver disease and glomerulonephritis. Using follow-up studies, differences in the dynamics of acquired AT III deficiency and coagulation promoting factors were demonstrated. 12 of 35 horses with decreased AT III values suffered from phlebothrombosis of the jugular veins. It was presumed that acquired AT III deficiencies promote development and progression of phlebothrombosis/thrombophlebitis in horses.

Animals↗

PubMed2001

Spirometric reference values in Estonian schoolchildren.

This study was conducted to describe the relationship between anthropometric parameters and lung function in Estonian children, to determine the reference values for spirometry, and to compare these results with other data sets. The results are based on 1170 healthy non-smoking children (643 girls and 527 boys), aged 6-18 years. The spiroanalyser Pneumoscreen II (Jaeger) was used to register dynamic lung parameters. Natural logarithmic values of lung volumes, standing or sitting height and age were used in the final regression model. Prediction equations for forced vital capacity (FVC), forced expiratory volume in 1 s (FEV1), peak expiratory flow, forced expiratory flows when 50 and 75% of FVC has been exhaled, and mean forced expiratory flow over the middle 50% of the FVC for both sexes are presented. In comparison with recent data from European children the reference values were close for FVC, the differences were bigger for FEV1 and forced expiratory flows, especially in taller children.

Adolescent↗

PubMed1992

The ICOH and IUPAC international programme for establishing reference values of metals.

In cooperation with the ICOH Scientific Committee on the Toxicology of metals and IUPAC Commission on Toxicology, we have developed evaluation criteria for derivation of reference values for metal concentrations in human tissues and fluids. In a first attempt to illustrate how these criteria may be used, tentative reference values for mercury in human blood were derived. For persons who do not eat fish, a mean value of 10 mumol/1 (2 micrograms/1) was suggested. It was pointed out, however, that this value was based on information that did not meet the desired quality requirements, which, unfortunately were not met by any of the published reports.

Animals↗

PubMed2003

Body composition estimated by bioelectrical impedance in the Swedish elderly. Development of population-based prediction equation and reference values of fat-free mass and body fat for 70- and 75-y olds.

OBJECTIVE: To develop a bioelectrical impedance (BIA) prediction equation for fat-free mass (FFM(BIA)) and present reference values of FFM and body fat (BF) for healthy Swedish elderly from population-based representative samples. SUBJECTS: This study is based on 823 (344 males, 479 females) participants from two systematic samples of birth cohorts in Göteborg aged 70 (cohort H70V, 201 males and 299 females) and 75 (cohort NORA75, 143 males and 180 females). METHODS: Body composition was measured with BIA (BIA-101, RJL system, Detroit) in both cohorts and was estimated by a four-compartment (4C) model from total body water (TBW) and total body potassium (TBK) in a sub-sample of the NORA75 cohort. The FFM(BIA) was validated against the FFM from the 4C model (FFM(4C)). RESULTS: The FFM(BIA) correlated well with FFM(4C) (r=0.95, SEE=2.64 kg). The FFM(BIA) (kg) in 70-y-old males and females were 58.5+/-5.4 and 43.4+/-4.4, and for 75-y-old males and females were 56.1+/-4.7 and 42.5+/-4, respectively. The body fat in kg (FM) among 70-y-old males and females were 25.2+/-8.1 and 25.7+/-8.4, and for 75-y-old males and females were 21.7+/-7.1 and 22.8+7.2, respectively. The percent body fat (BF%) among 70-y-old males and females were 29.5+/-5.8 and 36.3+/-6.4, and for 75-y-old males and females were 27.3+/-6 and 34.1+/-6.1, respectively. CONCLUSION: The FFM, FM and BF% from this study might be used as reference values for Swedish elderly aged 70 and 75 y.

Adipose Tissue↗

PubMed1996

Evaluation of selected publications on reference values for lead in blood.

As a part of the global Tracy project, whose aim is to define metal concentrations in tissues and body fluids of reference populations, more than 1000 papers published from 1980 to 1994 were scrutinized that presented tentative reference values for lead in blood in occupationally unexposed adult populations. Ten studies exemplifying criteria for proper sampling, analysis and data treatment are presented and discussed. Levels of lead in blood are influenced by numerous factors. Accordingly, a wide variation in blood lead concentrations was observed. As an example, in a global study in 1983 of nonsmoking female schoolteachers, the geometric mean value for lead in blood varied from 52 micrograms. l-1 in Tokyo, Japan, up to 193 micrograms. l-1 in Mexico City. The Tracy survey demonstrates the importance of factors such as age, gender, ethnicity, food, drinking and smoking habits, hobbies, season and year of sampling, residential area, and geographic location. Lead in blood was shown to be both time and area specific. Thus it was not possible to establish a general reference value for lead in blood.

Adult↗

PubMed1996

Energy and nutrient intakes in a sample of 136 Edinburgh 7-8 year olds: a comparison with United Kingdom dietary reference values.

Energy and nutrient intakes were assessed in 136 children, aged 7-8 years and living in and around Edinburgh, using the 7 d weighed inventory technique. The results were compared with UK dietary reference values (DRV) for energy, macronutrients and micronutrients. NSP intakes were compared with a calculated reference value (CRV). Mean energy intakes were close to the estimated average requirement for both boys and girls. Mean percentages of food energy derived from fat and saturated fat were high in relation to DRV (37 and 14 compared with 35 and 11 respectively). Mean percentage of food energy derived from total carbohydrate was close to the DRV of 50 but intakes of starch appeared to be low and intakes of total sugars high (23 and 26% food energy respectively). Superficially, this suggests that there is a need to alter the balance of carbohydrate in favour of increasing starch and lowering total sugar. There was, however, a clear 'fat-sugar seesaw', i.e. children with a high percentage energy from total sugars had a low percentage energy from fat, and vice versa. In view of this finding, it is possible that efforts to reduce total sugar intake in children may result in a further increase in percentage energy from fat. Mean intakes of NSP were only 50% of the CRV, but this guideline may be set too high. Mean intakes of most micronutrients were above reference nutrient intakes. Reported low intakes of Zn and Se were treated with caution due to the perceived incompleteness of the data for these in the nutrient database. The authors concluded that targeting high intakes of total fat and saturated fat should be the health priorities in this age-group.

Child↗

PubMed1998

Reference values of gastric intramucosal pH in children.

To determine the reference values of gastric intramucosal pH (pHi) by tonometry in paediatric patients, we studied 17 children (nine males, eight females) with no systemic or gastrointestinal disease, aged six months to 12 years undergoing minor reconstructive surgery. Following anaesthetic induction a sigmoid tonometry catheter was inserted (Tonometrics, Inc.) into the stomach of the patients under direct vision. All children were normoventilated and were haemodynamically stable. After an equilibration period of 30 min, gastric pHi was calculated by applying the Henderson-Hasselbalch equation on the PCO2 obtained with the tonometer and the bicarbonate from the arterial blood gas analysis. The mean gastric pHi in our patients was 7.35 +/- 0.06 (SD). The normal pHi in the general population is estimated to be 7.31-7.40, with a confidence interval of 99%. No correlation was found between pHi and arterial pH, bicarbonate or base excess. Under conditions of normal ventilation and haemodynamic stability, healthy children during general anaesthesia have gastric intramucosal values similar to those of adults.

Blood Chemical Analysis↗

PubMed1997

Percentile reference values of lipid risk factors of ischaemic heart disease: cholesterol, LDL-cholesterol, HDL-cholesterol and triglycerides in individuals aged 20 to 60 years in Plovdiv region.

1408 men and 1069 women aged 20 to 60 years selected at random from the Plovdiv region were studied during an epidemiological screening. Statistical analysis of the data was carried out using a SPSS/PC+ program. The percentiles (reference values and intervals) of the lipid risk factors were determined. The reference intervals and values at the 75th and 90th percentile for both sexes showed a prevalence of cholesterol, HDL-cholesterol and LDL-cholesterol for women, and of HDL-cholesterol at the 90th percentile for men below the age of 45 years. The derived percentile reference values for cholesterol, LDL-cholesterol and triglycerides are higher than the respective values for some European and American populations. A moderate and high lipid risk was identified for women over the age of 40-45 and in men in the age range 20-60 from all age groups. The established reference values for individuals of both sexes aged 20 to 60 years make it possible to diagnose and monitor dyslipidemias. They can be used for the purposes of the educational lipid program of the Plovdiv region population.

Adult↗

PubMed1978

Percentile estimates of reference values for fourteen chemical constituents in sera of children and adolescents.

The concentrations of 14 chemical constituents in sera of 1,062 children and adolescents aged 4 to 20 years were measured and their 5th and 95th percentiles were calculated. The distribution of values for all constituents showed significant deviation from the gaussian when the results were combined, regardless of age and sex, except for magnesium. Although certain chemical constituents showed statistically significant relationships with age and sex, two additional criteria based upon the coefficient of variation of the method employed were utilized to judge the effectiveness of computing stratified reference values. After applying these corrections the reference values established were classified into three categories, viz. (1) those where the relationship to age and sex remained significant (inorganic phosphorus and creatinine); (2) those where the relationship to age only remained significant (total protein); (3) those where no significant relationship to age and sex was obtained (all other constituents).

Adolescent↗

PubMed1978

Investigation of reference values of components of cerebrospinal fluid.

In order to obtain reference values, random samples of CSF from 70 women and 69 men were analyzed for various components, including total protein and protein fractions. Using statistical methods, data were also collected for sex differences and the influence of age. Small variations in the values of total protein, albumin and gamma-globulin between males and females were found, and slightly higher values for the gamma-globulin were found with increasing age.

Adult↗