High Pearson Correlation Research Articles

Fetal transcerebellar diameter measurement for prediction of gestational age in twins

This study was undertaken to determine the accuracy of our previously published and prospectively validated institution-specific singleton transcerebellar diameter (TCD) nomogram in the prediction of gestational age (GA) in twin pregnancies. We further evaluated whether the prediction of GA in twin gestations using the singleton TCD nomogram differs between monochorionic and dichorionic twins. In our previously published studies, we retrospectively constructed a cross-sectional nomogram using TCD measurements in 24,026 well-dated, singleton fetuses, and prospectively validated the nomogram using 2,597 singleton fetuses. The current study comprised of 1,278 well-dated twins (19.6% monochorionic) seen in our ultrasound unit between August 1994 and May 2003, and the singleton TCD nomogram was validated in these twin gestations. The actual GA was subtracted from the GA predicted by the TCD nomogram and the concordance between actual and predicted GAs was assessed on the basis of the Pearson's correlation coefficient (r). This was performed separately for monochorionic and dichorionic twins. Concordance between the actual and predicted twin TCD measurements based on our previously published singleton TCD nomogram was high (Pearson's correlation, r = 0.95, P < .0001). Between 16 and 23 weeks' gestation, the predicted mean GA was within 6 days of actual GA. Between 24 and 30 weeks, the predicted mean GA was within 3 days, and at 32 weeks or more, the predicted mean GA was within 5 days of the actual GA. Prediction of GA based on the singleton TCD nomogram was equally accurate in both monochorionic and dichorionic twin gestations (P = .686). This study demonstrates that our previously validated singleton TCD nomogram is reliable and accurate in twins irrespective of placental chorionicity.

The development of a semi-structured home interview (CHIF) to directly assess function in cognitively impaired elderly people in two cultures.

Assessing function is a crucial element in the diagnosis of dementia. This information is usually obtained from key informants. However, reliable informants are not always available. A 10-item semi-structured home interview (the CHIF, or Clinician Home-based Interview to assess Function) to assess function primarily by measuring instrumental activities of daily living directly was developed and tested for inter-rater reliability and validity as part of the Indianapolis-Ibadan dementia project. The primary validity measurements were correlations between scores on the CHIF and independently gathered scores on the Blessed Dementia Scale (from informants) and the Mini-mental State Examination (MMSE). Sensitivities and specificities of scores on the CHIF and receiver operator characteristic (ROC) curves were constructed with dementia as the dependent variable. Inter-rater reliability for the CHIF was high (Pearson's correlation coefficient 0.99 in Indianapolis and 0.87 in Ibadan). Internal consistency, in both samples, was good (Cronbach's alpha 0.95 in Indianapolis and 0.83 in Ibadan). Scores on the CHIF correlated well with the Blessed Dementia scores at both sites (-0.71, p < 0.0001 for Indianapolis and -0.56, p < 0.0001 for Ibadan) and with the MMSE (0.75, p < 0.0001 for Indianapolis and 0.44, p < 0.0001 for Ibadan). For all items at both sites, the subjects without dementia performed significantly better than those with dementia. The area under the ROC curve for dementia diagnosis was 0.965 for Indianapolis and 0.925 for Ibadan. The CHIF is a useful instrument to assess function directly in elderly participants in international studies, particularly in the absence of reliable informants.

The chemical nature of the 2′-substituent in the pentose-sugar dictates the pseudoaromatic character of the nucleobase (pKa) in DNA/RNA

We here show that the pKa (error limit: 0.01 to 0.03 pKa unit) of a nucleobase in a nucleotide can be modulated by the chemical nature of the 2'-substituent at the sugar moiety. This has been evidenced by the measurement of nucleobase pKa in 47 different model nucleoside 3',5'-bis- and 3'-mono-ethylphosphates. The fact that the electronic character of each of the 2'-substituents (Fig. 1) alters the chemical shift of the H2' sugar proton, and also alters the pKa of the nucleobase in the nucleotides has been evidenced by a correlation plot of pKa of N3 of pyrimidine (T/C/U) or pKa of N7 of 9-guaninyl with the corresponding deltaH2' chemical shifts at the neutral pH, which shows linear correlation with high Pearson's correlation coefficients (R = 0.85-0.97). That this modulation of the pKa of the nucleobase by a 2'-substituent is a through-bond as well as through-space effect has been proven by ab initio determined pKa estimation. Interestingly, experimental pKas of nucleobases from NMR titration and the calculated pKas (by ab initio calculations utilizing closed shell HF 6-31G** basis set) are linearly correlated with R = 0.98. It has also been observed that the difference of ground and protonated/de-protonated HOMO orbital energies (DeltaHOMO, a.u.) for the nucleobases (A/G/C/T/U) are well correlated with their pK(a)s in different 2'-substituted 3',5'-bis-ethylphosphate analogs suggesting that only the orbital energy of HOMO can be successfully used to predict the modulation of the chemical reactivity of the nucleobase by the 2'-substituent. It has also been demonstrated that pKa values of nucleobases in 3',5'-bis-ethylphosphates (Table 1) are well correlated with the change in dipole moment for the respective nucleobases after protonation or de-protonation. This work thus unambiguously shows that alteration of the thermodynamic stability (Tm) of the donor-acceptor complexes [ref. 20], as found with various 2'-modified duplexes in the antisense, siRNA or in triplexes by many workers in the field, is a result of alteration of the pseudoaromatic character of the nucleobases engineered by alteration of the chemical nature of the 2'-substitution.

Automatic classification of activity and apneas using whole body plethysmography in newborn mice

An increasing number of studies in newborn mice are being performed to determine the mechanisms of sleep apnea, which is the hallmark of early breathing disorders. Whole body plethysmography is the method of choice, as it does not require immobilization, which affects behavioral states and breathing. However, activity inside the plethysmograph may disturb the respiratory signal. Visual classification of the respiratory signal into ventilatory activity, activity-related disturbances, or apneas is so time-consuming as to considerably hamper the phenotyping of large pup samples. We propose an automatic classification of activity based on respiratory disturbances and of apneas based on spectral analysis. This method was validated in newborn mice on the day of birth and on postnatal days 2, 5, and 10, under normoxic and hypoxic (5% O(2)) conditions. For both activity and apneas, visual and automatic scores showed high Pearson's correlation coefficients (0.92 and 0.98, respectively) and high intraclass correlation coefficients (0.96-0.99), supporting strong agreement between the two methods. The present results suggest that breathing disturbances may provide a valid indirect index of activity in freely moving newborn mice and that automatic apnea classification based on spectral analysis may be efficient in terms of precision and of time saved.

Seasonal variation of the particle size distribution of polycyclic aromatic hydrocarbons and of major aerosol species in Claremont, California

As part of the Southern California Particle Center and Supersite (SCPCS) activities, we measured, during all seasons, particle size distributions of 12 priority pollutant polycyclic aromatic hydrocarbons (PAHs), concurrently with elemental carbon (EC), organic carbon (OC), sulfate (SO42−), and nitrate (NO3−) size distributions, from October 2001 to July 2002 in Claremont, CA, a receptor site located about 40 km downwind of central Los Angeles. Samples were collected approximately once every week, for 24-h periods, from midnight to midnight. MOUDI impactors collected samples at 30 LPM which were composited for analysis into monthly periods in three aerodynamic diameter size intervals, defined for the purpose of this work, as: 0–0.18 μm (ultrafine mode), 0.18–2.5 μm (accumulation mode), and 2.5–10 μm (coarse mode). For the monthly composites from October to February, the size distributions of the target PAHs are similar. However, from March to July, notable differences are observed: a significant fraction of the PAH mass is found in the coarse mode, as compared with the previous period. During the entire 1-year period, the form and shape of the EC size distributions did not vary much and are distinguished by prominent mass in the ultrafine and accumulation size mode. For the individual modes of the major species, the highest Pearson's correlation coefficients for the variation of temperature with species concentration were found in the ultrafine mode for both SO42− (0.92) and EC (0.90), and in the coarse mode for both OC (0.85) and NO3− (0.54). High SO42− correlations are consistent with increased gas-to-particle formation during the warmer months from (precursor) SO2 emissions in the Los Angeles and Lon Beach seaport areas and, similarly for EC, increased atmospheric transport to Claremont as the season progresses from winter to summer. Although not statistically significant, the correlations were negative for the less volatile or particle phase group (log [pLo]⩽−3.22), consistent with increased partitioning from the vapor phase with decreasing temperature.

Seasonal variation of the particle size distribution of polycyclic aromatic hydrocarbons and of major aerosol species in Claremont, California

Abstract As part of the Southern California Particle Center and Supersite (SCPCS) activities, we measured, during all seasons, particle size distributions of 12 priority pollutant polycyclic aromatic hydrocarbons (PAHs), concurrently with elemental carbon (EC), organic carbon (OC), sulfate (SO 4 2− ), and nitrate (NO 3 − ) size distributions, from October 2001 to July 2002 in Claremont, CA, a receptor site located about 40 km downwind of central Los Angeles. Samples were collected approximately once every week, for 24-h periods, from midnight to midnight. MOUDI impactors collected samples at 30 LPM which were composited for analysis into monthly periods in three aerodynamic diameter size intervals, defined for the purpose of this work, as: 0–0.18 μm (ultrafine mode), 0.18–2.5 μm (accumulation mode), and 2.5–10 μm (coarse mode). For the monthly composites from October to February, the size distributions of the target PAHs are similar. However, from March to July, notable differences are observed: a significant fraction of the PAH mass is found in the coarse mode, as compared with the previous period. During the entire 1-year period, the form and shape of the EC size distributions did not vary much and are distinguished by prominent mass in the ultrafine and accumulation size mode. For the individual modes of the major species, the highest Pearson's correlation coefficients for the variation of temperature with species concentration were found in the ultrafine mode for both SO 4 2− (0.92) and EC (0.90), and in the coarse mode for both OC (0.85) and NO 3 − (0.54). High SO 4 2− correlations are consistent with increased gas-to-particle formation during the warmer months from (precursor) SO 2 emissions in the Los Angeles and Lon Beach seaport areas and, similarly for EC, increased atmospheric transport to Claremont as the season progresses from winter to summer. Although not statistically significant, the correlations were negative for the less volatile or particle phase group (log [ p L o ]⩽−3.22), consistent with increased partitioning from the vapor phase with decreasing temperature.

Quantitative analysis and prognostic implication of SARS coronavirus RNA in the plasma and serum of patients with severe acute respiratory syndrome.

Background: The availability of an early diagnostic tool for severe acute respiratory syndrome (SARS) would have major public health implications. We investigated whether the SARS coronavirus (SARS-CoV) can be detected in serum and plasma samples during the early stages of SARS and studied the potential prognostic implications of such an approach. Methods: We developed two real-time quantitative reverse transcription-PCR (RT-PCR) assays, one for the polymerase and the other for the nucleocapsid region of the virus genome, for measuring the concentration of SARS-CoV RNA in serum/plasma samples from SARS patients. Plasma samples were obtained from 12 confirmed SARS patients on the day of hospital admission, as well as on days 7 and 14 after fever onset. Serum samples were also obtained from 23 confirmed SARS patients on the day of hospital admission, 11 of whom subsequently required intensive care. Viral RNA was extracted from the plasma/serum samples. The extracted RNA was subjected to analysis by the RT-PCR assays. Results: The RT-PCR system for the polymerase region detected SARS-CoV RNA in 50% of plasma and 78% of serum samples from SARS patients during the first week of illness. The detection rates for plasma dropped to 25% at day 14 after fever onset. The median serum SARS-CoV concentrations in patients who required and did not require intensive care unit admission during the course of hospitalization were 5800 and 140 copies/mL, respectively (Mann–Whitney test, P <0.005). These data were confirmed by the RT-PCR system for the nucleocapsid region, which showed an even higher detection rate of 87%. The correlation between the results obtained by the two RT-PCR systems was high (Pearson correlation analysis, r = 0.998; P <0.001). Conclusion: Plasma/serum SARS-CoV quantification represents a potentially useful early diagnostic and prognostic tool for SARS.

A Pilot Randomized Trial of Induced Blood Pressure Elevation: Effects on Function and Focal Perfusion in Acute and Subacute Stroke

Background: Small, unrandomized studies have indicated that pharmacologically induced blood pressure elevation may improve function in ischemic stroke, presumably by improving blood flow to ischemic, but noninfarcted tissue (which may be indicated by diffusion-perfusion mismatch on MRI). We conducted a pilot, randomized trial to evaluate effects of pharmacologically induced blood pressure elevation on function and perfusion in acute stroke. Methods: Consecutive series of patients with large diffusion-perfusion mismatch were randomly assigned to induced blood pressure elevation (‘treated’ patients, n = 9) or conventional management (‘untreated’ patients, n = 6). Results: There were no significant differences between groups at baseline. NIH Stroke Scale (NIHSS) scores were lower (better) in treated versus untreated patients at day 3 (mean 5.6 vs. 12.3; p = 0.01) and week 6–8 (mean 2.8 vs. 9.7; p < 0.04). Treated (but not untreated) patients showed significant improvement from day 1 to day 3 in NIHSS score (from mean 10.2 to 5.6; p < 0.002), cognitive score (from mean 58.7 to 27.9% errors; p < 0.002), and volume of hypoperfused tissue (mean 132 to 58 ml; p < 0.02). High Pearson correlations between the mean arterial pressure (MAP) and accuracy on daily cognitive tests indicated that functional changes were due to changes in MAP. Conclusion: Results warrant a full-scale, double-blind clinical trial to evaluate the efficacy and risk of induced blood pressure elevation in selective patients with acute/subacute stroke.

Revised formulas for summarizing retinal vessel diameters

Background/Purpose. Recent findings suggest that an objective assessment of retinal vessel caliber from fundus photographs provide information about the association of microvascular characteristics with macrovascular disease. Current methods used to quantify retinal vessel caliber, introduced by Parr and Hubbard, are not independent of scale and are affected by the number of vessels. To improve upon these methods we introduce revised formulas for quantifying vessel caliber. Methods. Revised formulas were estimated using retinal vessel measurements from 44 young adults free of hypertension and diabetes. Comparisons between the two methods were done using digitized photographs from 4926 participants at the baseline examination of the Beaver Dam Eye Study (BDES), an ongoing population-based cohort study initiated in 1987. Individual arterioles and venules were measured using semi-automated computer software from which summary measures were calculated. Results. Correlation coefficients between the Parr-Hubbard and revised formulas were high (Pearson correlation coefficients ranging from 0.94 to 0.98). Both arteriolar and venular caliber significantly increased with an increasing number of vessels measured using the Parr-Hubbard formulas (p < 0.001), which in turn affected the relationship to mean arterial blood pressure. To the contrary, the revised formulas were not affected by the number of measured vessels (p > 0.50). Conclusions. We describe revised formulas for summarizing retinal vessel diameters measured from fundus photographs to be used in future studies and analyses. The revised formulas correlate highly with the previously used Parr-Hubbard formulas, but offer the advantages of being more robust against variability in the number of vessels observed, being independent of image scale, and being easier to implement.

Journal co-citation analysis of semiconductor literature

The purpose of this study is to map semiconductor literature using journal co-citation analysis. The journal sample was gathered from the INSPEC database from 1978 to 1997. In the co-citation analysis, the data compiled were counts of the number of times two journal titles were jointly cited in later publications. It is assumed that the more two journals are cited together, the closer the relationship between them. The journal set used was the 30 most productive journals in the field of semiconductors. Counts of co-citations to the set of semiconductor journals were retrieved from SciSearch database, accessed through Dialog. Cluster analysis and multi-dimensional scaling were employed to create two-dimensional maps of journal relationships in the cross-citation networks. The following results were obtained through this co-citation study: The 30 journals fall fairly clearly into three clusters. The major cluster of journals, containing 17 titles, is in the subject of physics. The second cluster, consisting of 9 journals, includes journals primarily on material science. The remaining cluster represents research areas in the discipline of electrical and electronic engineering. All co-cited journals share similar co-citation profiles, reflected in high positive Pearson correlation. Two hundred and ninety-six pairs (68%) correlate at greater than 0.70. This shows that there is strong relationship between semiconductor journals. Five individual journals in five paired sets with co-citation frequency over 100,000 times include Physical Review B, Condensed Matter; Physical Review Letters; Applied Physics Letters; Journal of Applied Physics; and Solid State Communications.

Dental age estimation and third molars: a preliminary study

The aim of the present investigation was to reconstruct the chronological age based on the dental developmental stages of third molars evaluated on orthopantomograms. A total of 1175 orthopantomograms were assembled from patients of Caucasian origin between 16 and 22 years of age. Each third molar present was scored by two observers according to a 10-stage developmental scale. The κ statistics measured the intra- and inter-observer reliability. The general statistical analysis was based on multiple regression analysis in order to obtain multiple regression formulas for dental age estimation based on the number of third molars present on the evaluated orthopantomogram. No regression models were statistically significant when there was only one-third molar present because of the relatively small number of orthopantomograms that fitted this criterion. A strong agreement was found between the intra- and inter-observer measurements. The statistical analysis revealed both for males and females high Pearson correlation coefficients between contralateral third molars and smaller coefficients between antimeres. The obtained multiple regression formulas are only applicable in certain specified conditions, for instance when four third molars are present the following formulas should be used in a Caucasian male “age=10.2000+0.5122UL+0.5273LL” (developmental stage of upper and lower left third molars) or in case of a female “age=13.6206+0.1933UR+0.5080LR” (developmental stage of upper and lower right third molars). This investigation revealed that the chronological age of a Caucasian individual may be estimated based on regression formulas with a S.D. of 1.52 or 1.56 years for males and females, respectively, when all four third molars are present.

Validation of a Combined Enzymatic and HPLC Method for Screening of Pectins in Fruits of Japanese Quince ( Chaenomeles japonica)

A combined enzymatic and HPLC method was validated for analysis of galacturonic acid (GalA) in (1) alcohol-insoluble solids (AIS), and in (2) pectins, extracted from fruits of Japanese quince ( Chaenomeles japonica), by comparison with a standard colorimetric method (using metahydroxydiphenyl) for analysis of uronic acids (UA). For analysis of AIS, the results of the colorimetric and the enzymatic/HPLC methods were identical (UA and GalA in average 20 g/100 g AIS dry weight). For analysis of pectins, the colorimetric method resulted in consistently higher estimates (UA in average 63 g/100 g pectins dry weight) compared to the enzymatic/HPLC method (GalA in average 57 g/100 g pectins dry weight). The enzymatic/HPLC method also proved to be useful as a simple and efficient screening method, since a very high Pearson correlation ( R=0.93) was obtained between GalA estimates of the homogenized fruit sample and the AIS content of acid-extracted pectins.

The bioinformatics of microarray gene expression profiling.

The bioinformatics of microarray gene expression profiling.

Stabilization of blood homocysteine in an epidemiological setting

The major problem in the determination of homocysteine (Hcy), which is thought to be a risk factor in colorectal cancer, is the rise in its concentration if blood is not centrifuged immediately after collection. We assess the interference of 3-deazaadenosine (which inhibits conversion of S-adenosylhomocysteine into Hcy within the erythrocyte), using the fluorescence polarization immunoassay (FPIA) assay, the stabilizing effect of 3-deazaadenosine and the impact of temperature on Hcy stabilization. To assess interference of 3-deazaadenosine, 12 blood samples were extracted; two aliquots were obtained from each and one of them was added 3-deazaadenosine (50 micromol/l). To assess the stabilizing value of 3-deazaadenosine, as well as the effect of temperature, two blood samples were extracted from 24 volunteers. One of the tubes was immediately placed on ice and centrifuged (reference concentration). To the second tube was immediately added 3-deazaadenosine (50 micromol/l), producing six aliquots, three of which were kept at room temperature (25 degrees C) for 1, 4 and 6 hours, the other three kept at 37 degrees C. The mean values (standard deviation) obtained for methodological interference were: 7.32 (3.58) micromol/l without stabilizer, and 7.11 (3.61) micromol/l with stabilizer. There were no statistically significant differences (P = 0.104) and intraclass correlation coefficient was 0.989, suggesting no methodological interference. We did not find any significant differences regarding our reference value in the samples kept at room temperature during the interval studied. A high Pearson correlation coefficient was obtained. Nevertheless, in those samples kept at 37 degrees C, a slight increase was observed in the 4-hour period (P = 0.009). The addition of 3-deazaadenosine may avoid problems in the critical pre-analytical phase in the Hcy measurement. There is no interference with the FPIA assay, nor any dilution effect, and new reference values are not necessary.

Optimising learning competencies of grade 9 learners: A comparison between a few subject didactic measuring instruments.

The aim of this article is to compare three subject didactic measuring instruments (the SOM, LEMOSS(II) and LCH questionnaires) with regard to validity. These questionnaires are diagnostic measuring instruments, which teachers can use as an aid in certain didactic situations within the classroom. This includes the specialist planning of a specific learning opportunity, and as point of departure for the discussion of a learner’s learning competency in order to master specific and critical outcomes. High Pearson correlations between the different fields of the three measuring instruments, as well as between the measuring instruments as a whole, were found for grade nine learners in the Tzaneen and Phalaborwa areas. None of the questionnaires can be used as autonomous predictors of respective subject marks. However, the SOM, LEMOSS(II) and LCH questionnaires are diagnostic measuring instruments and therefore it is not of such critical importance for these questionnaires to be extremely accurate predictors of subject marks.

The catatonia rating scale I—Development, reliability, and use

The study objective is to present reliability data on the Catatonia Rating Scale (CRS). The CRS is a 21-item clinician-administered rating scale. Items are individually defined and are scored from 0 (absent) to 4 (severe). A definition for each degree of severity is provided for each item. The diagnostic threshold for catatonia is 4 symptoms rated at least 2 (moderate). The CRS requires, at most, 45 minutes to administer. Reliability data were evaluated in a sample of 120 inpatients, 71 of whom were catatonic. Ratings were performed by 4 pairs of raters. Interrater reliability was high (Pearson correlation coefficient = .91 to .99, intraclass correlation coefficient = .94 to .99). Internal consistency was very good (Cronbach's alpha = .8890). Analysis of individual items showed that all were frequently endorsed and occurred across a wide range of severity. The CRS is a reliable rating scale for the diagnosis of catatonia. Advantages of the scale, areas of use, and clinical implications are discussed.

The Inflammatory Bowel Disease Questionnaire: A Valid and Reliable Measure in Ulcerative Colitis Patients in the North East of England

Background: The validity and reliability of the Inflammatory Bowel Disease Questionnaire (IBDQ) needed to be confirmed before its use in the UK. Methods: The IBDQ was administered to 28 subjects with ulcerative colitis (UC) on 3 separate occasions over a period of 4 weeks, twice by an interviewer and once by self-completion. Convergent and concurrent validity was assessed by using the Colitis Activity Index (CAI) and the Short Form 36 Health Survey (SF-36). Test-retest reliability and internal consistency were also tested. Results: There were moderately high Pearson correlations between related IBDQ domains and SF-36 dimensions and also between the CAI score and the IBDQ Bowel domain and the SF-36 Pain dimension. Cronbach's alpha, corrected item-total correlations, and intra-class correlation coefficients were high. Conclusions: The IBDQ is a valid and reliable health-related quality of life scale for use in patients with UC and is suitable for use in the UK.

Neurologic markers of the progression of Alzheimer's disease.

This article describes the results of studies conducted to determine the usefulness of reflex changes as markers of disease severity in Alzheimer's disease (AD). Standardized and quantified muscle stretch reflexes, cutaneous reflexes, and developmental (primitive) reflexes were studied in normal older adults, in individuals with mild memory impairment, and in patients with AD, in all clinical severity stages as assessed with the Global Deterioration Scale (GDS), the Mini-Mental State Examination (MMSE), and the Functional Assessment Staging (FAST) procedure. Changes in frequency and intensity of these individual reflex variables, as well as of variables consisting of combinations of these individual reflexes, appeared to be sensitive indicators of the progression of AD. These neurological reflex variables showed high Pearson correlations with the GDS (.72), the MMSE (.74), and the FAST (.80). Standardized quantified neurological reflex measures are useful as noncognitive, education-independent, and culture-independent markers of the course of AD.

Acculturation Rating Scale for Mexican Americans-II: A Revision of the Original ARSMA Scale

The Acculturation Rating Scale for Mexican Americans (ARSMA) was revised for the purpose of developing an instrument that assessed acculturation processes through an orthogonal, multidimensional approach by measuring cultural orientation toward the Mexican culture and the Anglo culture independently. Two subscales, Anglo Orientation Subcale (AOS) and Mexican Orientation Subscale (MOS), were developed from items from the original ARSMA scale. The two cultural orientation subscales were found to have good internal reliabilities (Cronbach's Alpha = .86 and .88 for the AOS and the MOS, respectively. The revised scale (ARSMA-JJ) yielded a high Pearson correlation coefficient (r = .89) with the original scale. Strong construct validity of ARSMA -II was demonstrated using a sample of 379 individuals representing generations I to 5. ARSMA-II is multifactorial and capable of generating multidimensional acculturative types, for example, integrated, separated, assimilated and marginalized.

Relationship between delta checks for selected chemistry tests

The correlation between delta differences for 20 serum chemistry tests was calculated for 2400 samples from 288 patients. There were 12 pairs of chemistry tests for which correlation coefficients of the delta checks exceeded 0.25; aspartate aminotransferase and alanine aminotransferase had the highest Pearson correlation coefficient, 0.915. The highest negative, indirect, correlation was between the delta checks of bicarbonate and chloride (-0.219). The relationship between delta differences may be used as a quality-control technique to detect analytical errors.