Pearson's Correlation Coefficient (pearson + correlation_coefficient)

Distribution by Scientific Domains
Distribution within Medical Sciences


Selected Abstracts


Analysis of ,-globulin mobility on routine clinical CE equipment: Exploring its molecular basis and potential clinical utility

ELECTROPHORESIS, Issue 15 2009
Dieter Vanderschaeghe
Abstract A study was conducted on the variability of ,-globulin mobility in serum protein electrophoresis and its molecular basis. We found that the migration time of ,-globulins can be reproducibly determined (CV=1.1%) on clinical CE equipment. Moreover, we found a significant difference (p<0.001) in the migration of ,-globulins between chronic liver disease patients (n=98) and a healthy reference group (n=47). Serum immunoglobulins were purified from these patients' sera using protein L -agarose and their glycosylation was studied using CE on a DNA sequencer. This glycomics approach revealed that several non-sialylated N-glycans show a moderate Pearson correlation coefficient (r=0.2,0.4) with the migration time of ,-globulins. Their sialylated structures correlate negatively (r=,0.2 to ,0.3). Immunoglobulins are significantly more sialylated in the healthy reference group compared with the patients (p<0.001). We estimated that sialylation heterogeneity contributes about 36% to the molecular variance (carbohydrates and amino acid composition) that affects the electrophoretic mobility of immunoglobulins. This is the first report on the migration time of ,-globulins on a clinical CE instrument and its potential clinical value to the routinely analyzed serum protein CE profiles. [source]


Heart Rate Response to Intravenous Catheter Placement

ACADEMIC EMERGENCY MEDICINE, Issue 9 2003
Joel M. Bartfield MD
Abstract Objective: To investigate the relationship between change in heart rate and pain and anxiety caused by intravenous catheter (IV) placement. Methods: An observational study was performed in a university-based tertiary care emergency department. Patients who required IV placement as part of their management were considered as possible subjects. Heart rates were recorded at the following times: baseline, tourniquet placement, and IV placement. Immediately after IV placement, subjects recorded pain and anxiety scores using 100-mm visual analog scales. Percentage change in heart rate (compared with baseline) was calculated at time of tourniquet placement (anxiety) and IV placement (pain). Simple linear regression analyses were performed comparing pain scores with percent change in heart rate at the time of IV and tourniquet placement. Significance was defined as p < 0.05. Results: Ninety subjects were enrolled. Subjects had a mean age of 48 years, and 54% were women. There was a normal distribution of heart rate changes, with greater than 80% of all subjects having a 10% or less change in heart rates. The results of the analysis of pain scores versus percentage change in heart rate at IV placement yielded a Pearson correlation coefficient of 0.13 (p = 0.2). The results of the analysis of anxiety scores versus percentage change in heart rate at tourniquet placement yielded a Pearson correlation coefficient of 0.014 (p = 0.9). Conclusions: Changes in heart rate do not correlate with pain and anxiety associated with IV placement. [source]


Transepidermal water loss reflects permeability barrier status: validation in human and rodent in vivo and ex vivo models

EXPERIMENTAL DERMATOLOGY, Issue 7 2006
Joachim W. Fluhr
Abstract:, Permeability barrier function is measured with instruments that assess transepidermal water loss (TEWL), either with closed- or open-loop systems. Yet, the validity of TEWL as a measure of barrier status has been questioned recently. Hence, we tested the validity of this measure by comparing TEWL across a wide range of perturbations, with a variety of methods, and in a variety of models. TEWL rates with two closed-chamber systems (VapoMeter and H4300) and one closed-loop system (MEECO) under different experimental in vivo conditions were compared with data from four open-loop instruments, i.e. TM 210, TM 300, DermaLab and EP 1. The instruments were compared in vivo both in humans and hairless mice skin subjected to different degrees of acute barrier disruption. The values obtained with bioengineering systems were correlated with absolute water loss rates, determined gravimetrically. Measurements with both closed and open systems correlated not only with each other, but each method detected different degrees of barrier dysfunction. Although all instruments differentiated among gradations in TEWL in the mid-range of barrier disruption in vivo, differences in very low and very high levels of disruption were less accurately measured with the H4300 and DermaLab systems. Nevertheless, a high Pearson correlation coefficient (r) was calculated for data from all instruments vs. gravimetrically assessed TEWL. Together, these results verify the utility of TEWL as a measure of permeability barrier status. Moreover, all tested instruments are reliable tools for the assessment of variations in permeability barrier function. [source]


Chemical composition of the essential oils from Eriocephalus africanus L. var. africanus populations growing in Spain

FLAVOUR AND FRAGRANCE JOURNAL, Issue 6 2007
Hugo Merle
Abstract Essential oils from the aerial parts of three Eriocephalus africanus L. var. africanus populations were analysed by means of GC,FID and GC,MS. Sixty-one constituents were identified, representing more than 96% of the total oil composition. Artemisia ketone (56.46,56.58%), intermedeol (9.19,11.63%) and , -eudesmol (4.26,5.64%) were the main compounds. Application of the Pearson correlation coefficient showed high similarity between the nine samples analysed. Copyright © 2007 John Wiley & Sons, Ltd. [source]


Acrylonitrile content as a predictor of the captan permeation resistance for disposablenitrile rubber gloves

JOURNAL OF APPLIED POLYMER SCIENCE, Issue 3 2007
R. N. Phalen
Abstract The aim of this study was to determine whether the acrylonitrile (ACN) content influences the permeation resistance of disposable nitrile rubber (NBR) gloves to aqueous solutions of the pesticide captan. Attenuated total reflectance/Fourier transform infrared (ATR,FTIR) spectrophotometry at 2237 ± 5 cm,1 was used to measure the ACN contents of seven different NBR gloves. The ACN contents of the gloves ranged from 12.7 to 29.9%. Permeation was conducted according to American Society for Testing and Materials (ASTM) Method F 739-99a with a gas chromatography/mass spectrometry analysis of captan in the hexane collection liquid. Significant correlations were found between (1) the ACN content and mass-to-area ratio and the logarithm of the steady-state permeation rate (SSPR; Pearson correlation coefficient = 0.9227, p , 0.05), and (2) the ACN content and mass-to-area ratio and the ASTM normalized breakthrough detection time (NBT) at 0.25 ,g/cm2 (Pearson correlation coefficient = 0.9471, p , 0.05). On average, the NBT increased 120 min for every 5% increase in the ACN content. The average SSPR ranged from 0.002 to 0.40 ,g/cm2/min, a 200-fold difference. Increasing the ACN content resulted in decreased SSPR. ATR,FTIR was useful in determining the NBR polymer ACN content, surface homogeneity, and potential glove chemical resistance. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 103: 2057,2063, 2007 [source]


Administration of enoxaparin by continuous infusion in a naturalistic setting: analysis of renal function and safety,

JOURNAL OF CLINICAL PHARMACY & THERAPEUTICS, Issue 3 2005
S. L. Kane-Gill Pharm D MSc
Summary Study objective:, To describe the clinical use and safety of continuous infusion (CI) enoxaparin in a naturalistic setting and to evaluate the influence of renal function on enoxaparin elimination. Design:, Retrospective medical record review. Setting:, 1000-bed tertiary care teaching centre. Patients:, Hospitalized patients that received enoxaparin by CI during a 2-year period. Interventions:, None. Measurements:, Specific details of dosage and monitoring were collected. Adverse drug reactions (ADR) were recorded. Creatinine clearance (CrCl) was calculated using Cockroft and Gault and Brater equations. A population pharmacokinetic analysis was performed using the non-linear mixed effect model (NONMEM). For patients located in the intensive care unit (ICU) and ward, POSTHOC pharmacokinetic parameter estimates were evaluated using the Wilcoxon rank-sum. Pearson correlation coefficient was calculated to determine the association between renal function and anti-Xa clearance. Main results:, Sixty-seven patients received enoxaparin by CI of which 61·2% were in the ward and 38·8% in the ICU. The average initial rate and duration of infusion were 5·2 mg/h and 5·6 days, respectively. The number of anti-Xa concentration measurements averaged five per patient. Nine patients experienced an ADR. The most frequent ADR was gastrointestinal bleeding (n = 4). Among the 67 patients, 48 had available anti-Xa concentrations and were included in the NONMEM model. The anti-Xa CL and volume of distribution for ICU and ward patients averaged 0·64 ± 0·34 L/h, 10·6 ± 1·55 L and 1·01 ± 0·39 L/h, 9·08 ± 1·17 L, respectively. CrCl was not a significant covariate when included in the NONMEM model, and the association between CrCl and anti-Xa clearance was not significant (R2 = 0·0005; P = 0·8916). Conclusions:, This study is the first to report the use and safety of prolonged CI enoxaparin. Pharmacokinetic parameters of enoxaparin differ in ICU vs. ward patients. Overall, we found the safety of CI to be comparable to subcutaneous administration. Also, we found no effect of renal function on enoxaparin elimination. [source]


Different hip and knee priority score systems: are they good for the same thing?

JOURNAL OF EVALUATION IN CLINICAL PRACTICE, Issue 5 2010
Antonio Escobar MD PhD
Abstract Objective, The aim of the present study was to compare two priority tools used for joint replacement for patients on waiting lists, which use two different methods. Methods, Two prioritization tools developed and validated by different methodologies were used on the same cohort of patients. The first, an IRYSS hip and knee priority score (IHKPS) developed by RAND method, was applied while patients were on the waiting list. The other, a Catalonia hip,knee priority score (CHKPS) developed by conjoint analysis, was adapted and applied retrospectively. In addition, all patients fulfilled pre-intervention the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC). Correlation between them was studied by Pearson correlation coefficient (r). Agreement was analysed by means of intra-class correlation coefficient (ICC), Kendall coefficient and Cohern kappa. The relationship between IHKPS, CHKPS and baseline WOMAC scores by r coefficient was studied. Results, The sample consisted of 774 consecutive patients. Pearson correlation coefficient between IHKPS and CHKPS was 0.79. The agreement study showed that ICC was 0.74, Kendall coefficient 0.86 and kappa 0.66. Finally, correlation between CHKPS and baseline WOMAC ranged from 0.43 to 0.64. The results according to the relationship between IHKPS and WOMAC ranged from 0.50 to 0.74. Conclusions, Results support the hypothesis that if the final objective of the prioritization tools is to organize and sort patients on the waiting list, although they use different methodologies, the results are similar. [source]


Subthreshold Test Pulses Versus Low Energy Shock Delivery to Estimate High Energy Lead Impedance in Implanted Cardioverter Defibrillator Patients

PACING AND CLINICAL ELECTROPHYSIOLOGY, Issue 1p2 2003
DIRK VOLLMANN
VOLLMANN, D., et al.: Subthreshold Test Pulses Versus Low Energy Shock Delivery to Estimate High Energy Lead Impedance in Implanted Cardioverter Defibrillator Patients. The high energy lead impedance is valuable for detecting lead failure in ICDs, but until recently shock delivery was necessary for high energy impedance measurement. This study compared the use of subthreshold test pulses and low energy test shocks to estimate the high energy impedance. Immediately after implantation of Ventak Prizm ICDs in 29 patients, the lead impedance was measured with five subthreshold (0.4 ,J) test pulses, 5 low energy (1.1 J) shocks, and two to three high energy(16 ± 4.5 J)shocks. The mean impedances measured using high energy shocks, low energy shocks, and subthreshold pulses were42.0 ± 7.3 ,, 46.5 ± 8.1 ,, and42.4 ± 7.1 ,, respectively. The impedances measured using high and low energy shocks differed significantly(P <0.0001), while those obtained by high energy shocks and low energy pulses did not(P = 0.63). According to the Pearson correlation coefficient, the impedance measurements with subthreshold pulses and low energy shocks were both closely correlated(P < 0.0001)with impedance values determined with high energy shocks. However, while the impedance values tended to be higher when measured with low energy shocks, the concordance correlation coefficient (c) was higher for subthreshold test pulse versus high energy shock(c = 0.92)than for low versus high energy shock(c = 0.73). Furthermore, the intraindividual variability of impedance measurements was lower with subthreshold pulse measurements than with low energy shocks. Compared with low energy shocks, impedance measurement with subthreshold pulses has higher reproducibility and a higher correlation with the impedance obtained by high energy shock delivery. Safe and painless high energy impedance estimation with subthreshold pulses might, therefore, help to detect ICD lead failure during routine follow-up. (PACE 2003; 26:[Pt. II]:457,460) [source]


Hyperferritinemia and iron overload in type 1 Gaucher disease,

AMERICAN JOURNAL OF HEMATOLOGY, Issue 7 2010
Philip Stein
Hyperferritinemia occurs in Gaucher disease but its clinical spectrum or its association with systemic iron overload and HFE mutations are not known. In 114 patients with Type 1 Gaucher disease, we determined serum ferritin, transferrin saturation and HFE genotype. The results were correlated with the extent of hepatosplenomegaly, overall Gaucher disease severity score index, and response to enzyme replacement therapy. In a subset of patients with radiological and/or laboratory evidence of systemic iron overload, liver biopsy was performed. There was a mean 3.7-fold elevation of serum ferritin over the upper limit of normal (ULN). Prior splenectomy was associated with most severe hyperferritinemia compared to patients with intact spleen (6.53 × ULN vs. 2.69 × ULN, P = 0.003). HFE genotyping revealed two patients homozygous for H63D mutation and 30% of patients heterozygote carriers of H63D mutation; no patients harbored C282Y mutation; there was no correlation of ferritin with HFE genotype. Ferritin level correlated with liver volume (Pearson correlation coefficient = 0.254, P = 0.035) and it was negatively correlated with hemoglobin (r = ,0.315, P = 0.004); there was no relationship with other indicators of Gaucher disease activity. Enzyme replacement therapy (ERT) resulted in amelioration of hyperferritinemia: 707 ± 898 ng/ml vs. 301 ± 310 ng/ml (P = 0.001), transferrin saturation remained normal. Three patients were suspected of clinical iron overload, confirmed on liver biopsy. Iron accumulation was variably noted in hepatocytes and Kupffer cells. There is a high prevalence of hyperferritinemia in Type 1 Gaucher disease that is associated with indicators of disease severity, reversed by ERT and is not related to HFE mutations. Am. J. Hematol. 2010. © 2010 Wiley-Liss, Inc. [source]


Activation of Signal Transducers and Activators of Transcription 3 and Overexpression of its Target Gene CyclinD1 in Laryngeal Carcinomas,

THE LARYNGOSCOPE, Issue 11 2008
Bin Liu MD
Abstract Objectives/Hypothesis: Constitutive activation of signal transducers and activators of transcription (STAT) 3 has been observed in many solid tumors including head and neck squamous cell carcinoma. Expression and activation of STAT3 in laryngeal carcinoma have not been fully understood. The study aims to investigate the expression and activation of STAT3 in laryngeal carcinoma, the relationship between activated STAT3 and its downstream target gene CyclinD1 and the related clinicopathological factors of activated STAT3. Study Design: Prospective. Methods: Sixty-four samples of laryngeal squamous cell carcinoma and 12 samples of control mucosa obtained from total laryngectomy cases were analyzed using Western blot analysis and reverse transcriptase-polymerase chain reaction. Statistical analysis was performed using SPSS. Results: The overexpression of both STAT3 and CyclinD1 mRNA was observed in all samples of laryngeal squamous cell carcinoma. The mRNA levels of STAT3 and CyclinD1 in carcinoma tissue were 2.1- and 2.3-fold higher than those in control mucosa, respectively; the differences were statistically significant (P < .01). The overexpression of STAT3, p-STAT3, and CyclinD1 protein was also observed in all tumor samples. The protein levels of STAT3, p-STAT3, and CyclinD1 in carcinoma tissue were 1.6-, 4.5-, and 2.0-fold higher than those in control mucosa respectively; the differences were statistically significant (P < .01). There was a positive correlation between p-STAT3 protein and CyclinD1 mRNA (Pearson correlation coefficient = 0.827, P < .01). There were significant correlations between the overexpression of p-STAT3 protein and clinical T stage (P < .01), and tumor size (P < .05). The p-STAT3 protein level of patients in T1, T2 was higher than that of patients in T3, T4. The p-STAT3 protein level of patients with tumor size within 20 mm was higher than that of patients with tumor size more than 20 mm. Conclusions: High expression and activation of STAT3 exist in laryngeal carcinomas. Activated STAT3 may take effect on promoting transcription of its downstream target gene CyclinD1. The role of activation of STAT3 in laryngeal carcinogenesis needs further research. [source]


Development and Validation of the Excess Mortality Ratio,adjusted Injury Severity Score Using the International Classification of Diseases 10th Edition

ACADEMIC EMERGENCY MEDICINE, Issue 5 2009
Jaiyong Kim MD
Abstract Objectives:, This study aimed to develop and validate a new method for measuring injury severity, the excess mortality ratio,adjusted Injury Severity Score (EMR-ISS), using the International Classification of Diseases 10th Edition (ICD-10). Methods:, An injury severity grade similar to the Abbreviated Injury Scale (AIS) was converted from the ICD-10 codes on the basis of quintiles of the EMR for each ICD-10 code. Like the New Injury Severity Score (NISS), the EMR-ISS was calculated from three maximum severity grades using data from the Korean National Injury Database. The EMR-ISS was then validated using the Hosmer-Lemeshow goodness-of-fit chi-square (HL chi-square, with lower values preferable), the area under the receiver operating characteristic curve (AUC-ROC), and the Pearson correlation coefficient to compare it with the International Classification of Diseases 9th Edition,based Injury Severity Score (ICISS). Nationwide hospital discharge abstract data (DAD) from stratified-sample general hospitals (n = 150) in 2004 were used for an external validation. Results:, The total number of study subjects was 29,282,531, with five subgroups of particular interest identified for further study: traumatic brain injury (TBI, n = 3,768,670), traumatic chest injury (TCI, n = 1,169,828), poisoning (n = 251,565), burns (n = 869,020), and DAD (n = 26,374). The HL chi-square was lower for EMR-ISS than for ICISS in all groups: 42,410.8 versus 55,721.9 in total injury, 7,139.6 versus 20,653.9 in TBI, 6,603.3 versus 4,531.8 in TCI, 2,741.2 versus 9,112.0 in poisoning, 764.4 versus 4,532.1 in burns, and 28.1 versus 49.4 in DAD. The AUC-ROC for death was greater for EMR-ISS than for ICISS: 0.920 versus 0.728 in total injury, 0.907 versus 0.898 in TBI, 0.675 versus 0.799 in TCI, 0.857 versus 0.900 in poisoning, 0.735 versus 0.682 in burns, and 0.850 versus 0.876 in DAD. The Pearson correlation coefficient between the two scores was ,0.68 in total injury, ,0.76 in TBI, ,0.86 in TCI, ,0.69 in poisoning, ,0.58 in burns, and ,0.75 in DAD. Conclusions:, The EMR-ISS showed better calibration and discrimination power for prediction of death than the ICISS in most injury groups. The EMR-ISS appears to be a feasible tool for passive injury surveillance of large data sets, such as insurance data sets or community injury registries containing diagnosis codes. Additional further studies for external validation on prospectively collected data sets should be considered. [source]


Cross-cultural evaluation of the Panic Disorder Severity Scale in Japan

DEPRESSION AND ANXIETY, Issue 1 2004
Ikuyo Yamamoto M.D.
Abstract The Panic Disorder Severity Scale (PDSS) [Shear et al., 1997] is rapidly gaining world-wide acceptance as a standard global severity measure of panic disorder, however, its cross-cultural validity and reliability have not been reported yet. We developed the Japanese version of the PDSS and examined its factor structure, internal consistency and inter-rater reliability and concurrent validity among Japanese patients with panic disorder with or without agoraphobia. We also established rules of thumb for interpreting PDSS total scores, taking the Clinical Global Impression severity scale as the anchoring criterion. The identical one-factor structure of the PDSS was confirmed among the Japanese patients as among the United States patients. Both internal and inter-rater reliability was excellent (Cronbach's alpha was 0.86, and ANOVA ICCs were all above 0.90). Concurrent validity of the PDSS items with self-report questionnaires tapping similar or overlapping domains was satisfactory (Pearson correlation coefficients were mostly above 0.5). Using the anchor-based approach, the following interpretative guides are suggested: among those with established panic disorder diagnosis, PDSS total scores up to 10 correspond with "mild," those between 11 and 15 with "moderate," and those at or above 16 correspond with "severe" panic disorder. The present findings support the cross-cultural generalizability of panic disorder symptomatology and of the PDSS, in particular. Depression and Anxiety 20:17,22, 2004. © 2004 Wiley-Liss, Inc. [source]


Association between cognition and daily life functioning in dementia subtypes

INTERNATIONAL JOURNAL OF GERIATRIC PSYCHIATRY, Issue 7 2009
Sharon F. M. Bouwens
Abstract Objective To investigate the association between cognition and daily life functioning in dementia subtypes. Methods Cross-sectional data were used from 615 patients with dementia who were referred to the Maastricht Memory Clinic of the Maastricht University Medical Centre. Pearson correlation coefficients were calculated between the Mini-Mental State Examination (MMSE; to measure cognitive status) and the Blessed Dementia Scale (BDS; to measure daily life functioning) for the following types of dementia: Alzheimer's Disease (AD, n,=,442); Vascular dementia (VaD, n,=,113); frontotemporal dementia (FTD, n,=,18); Parkinson's dementia (PD, n,=,21); and primary progressive aphasia (PPA, n,=,21). One-way ANOVA was used to test differences in age, MMSE scores and BDS scores across dementia subtypes. Results Scores on the MMSE showed strong correlation with BDS scores in cases of FTD (r,=,,0.80); moderate correlation in cases of AD, VaD, and PD (range r,=,,0.50,0.60); while no correlation was found in PPA cases. Conclusions The association between cognition and daily life functioning varied among dementia subtypes for AD, VaD, FTD and PD. Furthermore, the overall scores on both domains differ between dementia subtypes, indicating that different types of dementia are characterized by a specific pattern of cognitive status and daily life functioning. These findings underline the need for multidomain assessment in patients with dementia. Copyright © 2009 John Wiley & Sons, Ltd. [source]


Development of a Korean version of the behavior rating scale for dementia (BRSD-K)

INTERNATIONAL JOURNAL OF GERIATRIC PSYCHIATRY, Issue 7 2008
Jong Chul Youn
Abstract Objective The purpose of this study was to develop a Korean version of the behavior rating scale for dementia (BRSD-K) for evaluating behavioral and psychological symptoms of dementia. Methods The BRSD-K was administered to the informants of 268 subjects with dementia. Internal, inter-rater and test,retest reliabilities were tested. To evaluate construct validity, exploratory factor analysis was performed. To evaluate concurrent validity, Pearson correlation coefficients between BRSD-K scores and the corresponding scores of the Korean version of the neuropsychiatric inventory (NPI-K) were calculated. Results BRSD-K demonstrated substantially high levels of reliabilities. Factor analysis identified seven factors, i.e. depressive symptoms, irritability/aggression, psychotic symptoms, behavioral dysregulations, sleep disturbance, inertia, and appetite. Correlations between BRSD-K and corresponding NPI-K scores were statistically significant (p,<,0.05). Conclusions BRSD-K was found to be a reliable and valid instrument for evaluating BPSD. Copyright © 2007 John Wiley & Sons, Ltd. [source]


Performance evaluation of the PENTRA 60C+ automated hematology analyzer and comparison with the ADVIA 2120

INTERNATIONAL JOURNAL OF LABORATORY HEMATOLOGY, Issue 2 2009
K. GUERTI
Summary The PENTRA 60C+ hematology analyzer provides a complete blood cell (CBC) count, including a five-part differential (5-DIFF) count and two leukocyte subpopulations, i.e. large immature cells (LIC's) and atypical lymphocytes (ALY's). We evaluated its analytical performance and assessed agreement with the ADVIA 2120, in order to install the analyzer in a small satellite hematology laboratory. First we assessed repeatability, reproducibility and carry-over to evaluate the analytical performance. Then we used Pearson correlation coefficients, Passing and Bablok regression analysis and a graphical approach (n = 209) to evaluate agreement with the ADVIA 2120. Repeatability and reproducibility were excellent for the majority of CBC and 5-DIFF count parameters. Carry-over was negligible. Our data showed very good correlation for most CBC count parameters. Lower correlation coefficients were observed for red cell distribution width, mean corpuscular volume and mean platelet volume. As compared to the ADVIA 2120, the 5-DIFF count performed very well. Agreement was poorer for low-level eosinophils and basophils. Furthermore, the PENTRA 60C+ was equally able to identify pathological blood samples through the determination of LIC's and ALY's. Therefore, the PENTRA 60C+ is an eligible blood cell counter to be operational in a satellite laboratory setting. [source]


Susceptibility Contrast and Arterial Spin Labeled Perfusion MRI in Cerebrovascular Disease

JOURNAL OF NEUROIMAGING, Issue 1 2003
Ronald L. Wolf MD
ABSTRACT Purpose. To directly compare dynamic susceptibility contrast (DSC) and continuous arterial spin labeled (CASL) magnetic resonance (MR) perfusion techniques in patients with known cerebrovascular disease, with the goals of identifying possible pitfalls in interpretation and determining potential for a complementary role in this setting. Methods. DSC and CASL MR perfusion studies were performed and compared in 11 patients with acute and/or chronic cerebrovascular disease. Using an automated segmentation technique, Pearson correlation coefficients were generated for CASL perfusion measurements compared to DSC perfusion maps (time-to-peak [TTP], relative cerebral blood volume [rCBV], cerebral blood flow [rCBF], and mean transit time [MTT]) by hemisphere and vascular territory. Results. TTP maps obtained using DSC perfusion MR correlated best both subjectively and objectively with CASL perfusion MRmeasurements when all patients studied were considered. If patients with a major transit delay were excluded, DSC rCBF correlated best with CASL CBF measurements. Conclusion. There may be a complementary role for CASL and DSC perfusion MR methods in cerebrovascular disease, especially in the setting of a marked transit delay. [source]


Relocation into a new building and its effect on uncertainty and anxiety among psychiatric patients

JOURNAL OF PSYCHIATRIC & MENTAL HEALTH NURSING, Issue 5 2005
I. KAGAN rn ma
The study was designed to investigate the relationship between uncertainty and state anxiety among psychiatric patients before the closed wards of a psychiatric hospital were relocated to new premises. Patients from four psychiatric departments completed a structured questionnaire a week before, and six weeks after, relocation. Inter-variable relationships were assessed by Pearson correlation coefficients. The participants demonstrated moderate levels of pre-relocation uncertainty and anxiety. A significant correlation was found between anxiety and uncertainty both before and after the relocation. Anxiety after the relocation was significantly lower. There was statistical association between uncertainty and state anxiety. This study highlights the need to prepare patients and provide interventions relieving anxiety and lowering uncertainty before environmentally stressful events, such as relocation to a new building. [source]


Comparison of body fat estimates using 3D digital laser scans, direct manual anthropometry, and DXA in men,,§¶

AMERICAN JOURNAL OF HUMAN BIOLOGY, Issue 5 2010
Todd N. Garlie
Objectives: The purpose of this study was to assess the feasibility of utilizing three dimensional whole body laser surface scanning (3DS) to obtain specific anthropometric measurements to estimate percent body fat (BF). Methods: Percent BF estimates from 37 male volunteers, of age 18,62 yr, were determined by inputting manual anthropometric (MA) and 3DS anthropometric measurements into the current Army BF prediction equation for males. The results were compared with each other and to BF values from Dual Energy X-ray Absorptiometry (DXA), employed as a reference method. Results: Mean percent BF estimates (±SD) derived from MA, 3DS and from DXA were 18.4(±3.8), 18.8(±3.9), and 18.9(±4.7), respectively. Analysis of Variance tests revealed no statistical difference between the mean values. Correlation analysis comparing MA and 3DS derived percent BF estimates to each other and to those measured by DXA revealed moderate to strong Pearson correlation coefficients (r), small to moderate standard errors of the estimate (SEE), and were statistically significant (p < 0.05). Conclusions: Correlation coefficients and SEE results for this sample were: (1) DXA vs 3DS; r = 0.74, SEE = 3.2, (2) MA vs DXA; r = 0.82, SEE = 2.8, and (3) MA vs 3DS; r = 0.96, SEE = 1.0. Lin's concordance analysis, including Bland-Altman limits of agreement (LOA), revealed statistically significant measurement agreement among the three measurement modalities (p < 0.05). The application of 3DS scanning to estimate percent BF from commonly used anthropometric measurements are in close agreement with BF estimates derived from analogous MA measurements and from DXA scanning. Am. J. Hum. Biol. 22:695-701, 2010. Published 2010Wiley-Liss, Inc. [source]


Dental wear, wear rate, and dental disease in the African apes

AMERICAN JOURNAL OF PRIMATOLOGY, Issue 6 2010
Alison A. Elgart
Abstract The African apes possess thinner enamel than do other hominoids, and a certain amount of dentin exposure may be advantageous in the processing of tough diets eaten by Gorilla. Dental wear (attrition plus abrasion) that erodes the enamel exposes the underlying dentin and creates additional cutting edges at the dentin-enamel junction. Hypothetically, efficiency of food processing increases with junction formation until an optimal amount is reached, but excessive wear hinders efficient food processing and may lead to sickness, reduced fecundity, and death. Occlusal surfaces of molars and incisors in three populations each of Gorilla and Pan were videotaped and digitized. The quantity of incisal and molar occlusal dental wear and the lengths of dentin,enamel junctions were measured in 220 adult and 31 juvenile gorilla and chimpanzee skulls. Rates of dental wear were calculated in juveniles by scoring the degree of wear between adjacent molars M1 and M2. Differences were compared by principal (major) axis analysis. ANOVAs compared means of wear amounts. Pearson correlation coefficients were calculated to compare the relationship between molar wear and incidence of dental disease. Results indicate that quantities of wear are significantly greater in permanent incisors and molars and juvenile molars of gorillas compared to chimpanzees. The lengths of dentin,enamel junctions were predominantly suboptimal. Western lowland gorillas have the highest quantities of wear and the most molars with suboptimal wear. The highest rates of wear are seen in Pan paniscus and Pan t. troglodytes, and the lowest rates are found in P.t. schweinfurthii and G. g. graueri. Among gorillas, G. b. beringei have the highest rates but low amounts of wear. Coefficients between wear and dental disease were low, but significant when all teeth were combined. Gorilla teeth are durable, and wear does not lead to mechanical senescence in this sample. Am. J. Primatol. 72:481,491, 2010. © 2010 Wiley-Liss, Inc. [source]


Measuring effectiveness of TQM training: an Indian study

INTERNATIONAL JOURNAL OF TRAINING AND DEVELOPMENT, Issue 3 2003
Sasmita Palo
Total Quality Management (TQM) is a never ending process of improving work processes. It operates according to the premise that organisations cannot rest comfortably without continuously improving whatever is being done. There has to be a culture of continuous improvement and everyone in the organisation must strive towards it. This could be accomplished only through continuous training. The present study seeks to examine the role of training as well as measuring its effectiveness for successful implementation of TQM. For this purpose, data have been retrieved from a public sector enterprise manufacturing crude steel in India. The findings of the study are based purely on primary survey. Pearson's Correlation Coefficient with their significance levels have been used to measure the effectiveness of TQM training and the correlation between TQM training and selected factors. The authors have found that training creates awareness, builds employees' commitment to quality policy and strategy, facilitates teamwork, enhances performance standards, and bolsters the skills and abilities of employees. However, the organisation needs to focus more upon improving communication competencies, multiple skill development and customer value training. Successful TQM training in the organisation needs more budgetary allocation and commitment, support and enthusiasm of the top management. [source]


Relation between spasticity and strength in individuals with spastic diplegic cerebral palsy

DEVELOPMENTAL MEDICINE & CHILD NEUROLOGY, Issue 3 2002
Sandy A Ross MHS PT PCS
The relation between spasticity and strength in individuals with cerebral palsy (CP) has not been extensively researched. Knee and ankle spasticity and strength were quantified in a retrospective analysis of 60 individuals with spastic diplegic CP (mean age 12 years, range 3 to 38) and a group of 50 individuals without disabilities (WD group; mean age 12 years, range 4 to 36). Spasticity was measured using a KinCom dynamometer that stretched the passive knee flexors or ankle plantarflexors at different speeds and recorded the amount of resistive torques. For the strength tests, the participant performed a maximum contraction of the knee flexors/extensors and ankle plantarflexors/dorsiflexors throughout their range of motion at a speed of 10/s on the dynamometer. Pearson's correlation coefficient was used to determine if a relation existed between spasticity and strength within the same muscle group and in opposing muscle groups at the knee and ankle joints. A t-test was performed to determine if greater spasticity and less strength existed at the ankles compared with the knees in those with CP. Results show that there was no relation between spasticity and strength either within the same muscle group or at opposing muscle groups at the knee and ankle joints in persons with CP. Individuals with spastic diplegic CP were more involved (greater spasticity, less strength) distally at the ankles compared with the knees. The findings conflict with the literature, which contains several assumptions, one of which is that a spastic muscle is a strong muscle and that spasticity causes weakness in the opposing muscle group. We found no relation between spasticity and strength in individuals with CP. Our findings support the literature, which states that individuals with spastic diplegic CP are more involved distally compared with proximally in the lower extremities. [source]


Representing genetic variation as continuous surfaces: an approach for identifying spatial dependency in landscape genetic studies

ECOGRAPHY, Issue 6 2008
Melanie A. Murphy
Landscape genetics, an emerging field integrating landscape ecology and population genetics, has great potential to influence our understanding of habitat connectivity and distribution of organisms. Whereas typical population genetics studies summarize gene flow as pairwise measures between sampling localities, landscape characteristics that influence population genetic connectivity are often continuously distributed in space. Thus, there are currently gaps in both the ability to analyze genotypic data in a continuous spatial context and our knowledge of expected of landscape genetic structure under varying conditions. We present a framework for generating continuous "genetic surfaces", evaluate their statistical properties, and quantify statistical behavior of landscape genetic structure in a simple landscape. We simulated microsatellite genotypes under varying parameters (time since vicariance, migration, effective population size) and used ancestry (q) values from STRUCTURE to interpolate a genetic surface. Using a spatially adjusted Pearson's correlation coefficient to test the significance of landscape variable(s) on genetic structure we were able to detect landscape genetic structure on a contemporary time scale (,5 generations post vicariance, migration probability ,0.10) even when population differentiation was minimal (FST,0.00015). We show that genetic variation can be significantly correlated with geographic distance even when genetic structure is due to landscape variable(s), demonstrating the importance of testing landscape influence on genetic structure. Finally, we apply genetic surfacing to analyze an empirical dataset of black bears from northern Idaho USA. We find black bear genetic variation is a function of distance (autocorrelation) and habitat patch (spatial dependency), consistent with previous results indicating genetic variation was influenced by landscape by resistance. These results suggest genetic surfaces can be used to test competing hypotheses of the influence of landscape characteristics on genetic structure without delineation of categorical groups. [source]


Language lateralization in temporal lobe epilepsy using functional MRI and probabilistic tractography

EPILEPSIA, Issue 8 2008
Sebastian Rodrigo
Summary Purpose: Language functional magnetic resonance imaging (fMRI) is used to noninvasively assess hemispheric language specialization as part of the presurgical work-up in temporal lobe epilepsy (TLE). White matter asymmetries on diffusion tensor imaging (DTI) may be related to language specialization as shown in controls and TLE. To refine our understanding of the effect of epilepsy on the structure,function relationships, we focused on the arcuate fasciculus (ArcF) and the inferior occipitofrontal fasciculus (IOF) and tested the relationship between DTI- and fMRI-based lateralization indices in TLE. Methods: fMRI with three language tasks and DTI were obtained in 20 patients (12 right and 8 left TLE). The ArcF, a major language-related tract, and the IOF were segmented bilaterally using probabilistic tractography to obtain fractional anisotropy (FA) lateralization indices. These were correlated with fMRI-based lateralization indices computed in the inferior frontal gyrus (Pearson's correlation coefficient). Results: fMRI indices were left-lateralized in 16 patients and bilateral or right-lateralized in four. In the ArcF, FA was higher on the left than on the right side, reaching significance in right but not in left TLE. We found a positive correlation between ArcF anisotropy and fMRI-based lateralization indices in right TLE (p < 0.009), but not in left TLE patients. No correlation was observed for the IOF. Conclusions: Right TLE patients with more left-lateralized functional activations also showed a leftward-lateralized arcuate fasciculus. The decoupling between the functional and structural indices of the ArcF underlines the complexity of the language network in left TLE patients. [source]


Temporal coherence of two alpine lake basins of the Colorado Front Range, U.S.A.

FRESHWATER BIOLOGY, Issue 3 2000
J. I. L. L. S. Baron
1. Knowledge of synchrony in trends is important to determining regional responses of lakes to disturbances such as atmospheric deposition and climate change. We explored the temporal coherence of physical and chemical characteristics of two series of mostly alpine lakes in nearby basins of the Colorado Rocky Mountains. Using year-to-year variation over a 10-year period, we asked whether lakes more similar in exposure to the atmosphere be-haved more similarly than those with greater influence of catchment or in-lake processes. 2. The Green Lakes Valley and Loch Vale Watershed are steeply incised basins with strong altitudinal gradients. There are glaciers at the heads of each catchment. The eight lakes studied are small, shallow and typically ice-covered for more than half the year. Snowmelt is the dominant hydrological event each year, flushing about 70% of the annual discharge from each lake between April and mid-July. The lakes do not thermally stratify during the period of open water. Data from these lakes included surface water temper-ature, sulphate, nitrate, calcium, silica, bicarbonate alkalinity and conductivity. 3. Coherence was estimated by Pearson's correlation coefficient between lake pairs for each of the different variables. Despite close geographical proximity, there was not a strong direct signal from climatic or atmospheric conditions across all lakes in the study. Individual lake characteristics overwhelmed regional responses. Temporal coherence was higher for lakes within each basin than between basins and was highest for nearest neighbours. 4. Among the Green Lakes, conductivity, alkalinity and temperature were temporally coherent, suggesting that these lakes were sensitive to climate fluctuations. Water tem-perature is indicative of air temperature, and conductivity and alkalinity concentrations are indicative of dilution from the amount of precipitation flushed through by snowmelt. 5. In Loch Vale, calcium, conductivity, nitrate, sulphate and alkalinity were temporally coherent, while silica and temperature were not. This suggests that external influences are attenuated by internal catchment and lake processes in Loch Vale lakes. Calcium and sulphate are primarily weathering products, but sulphate derives both from deposition and from mineral weathering. Different proportions of snowmelt versus groundwater in different years could influence summer lake concentrations. Nitrate is elevated in lake waters from atmospheric deposition, but the internal dynamics of nitrate and silica may be controlled by lake food webs. Temperature is attenuated by inconsistently different climates across altitude and glacial meltwaters. 6. It appears that, while the lakes in the two basins are topographically close, geologically and morphologically similar, and often connected by streams, only some attributes are temporally coherent. Catchment and in-lake processes influenced temporal patterns, especially for temperature, alkalinity and silica. Montane lakes with high altitudinal gradients may be particularly prone to local controls compared to systems where coherence is more obvious. [source]


Inter-rater and test,retest reliability of three contingent valuation question formats in south-east Nigeria

HEALTH ECONOMICS, Issue 5 2005
Obinna Onwujekwe
Abstract This paper examines the inter-rater and test,retest reliability of willingness to pay (WTP) for insecticide-treated mosquito nets and net re-treatment using the bidding game (BG), binary with follow-up (BWFU) and a novel structured haggling technique (SH). Inter-rater reliability was evaluated by having two sets of interviewers administer questionnaires to 109 (BG), 110 (BWFU) and 103 (SH) randomly selected household heads. Test,retest reliability was investigated by repeating interviews on 146 (BG), 161 (BWFU) and 139 (SH) household heads one month after an initial survey. Data analysis used testing of means, Spearman's correlation and Pearson's correlation coefficient for test of reliability, while non-parametric analysis was used to determine factors causing a variation in WTP. The study was conducted in Southeast Nigeria. Inter-rater reliability coefficients were estimated for the individual's WTP for own nets, WTP for others and WTP for re-treatment. Using WTP for own nets as the best reliability estimate, the coefficients were high at values of 0.77 (C.I. 0.72,0.86), 0.75 (C.I. 0.64,0.81) and 0.74 (C.I. 0.63,0.82) in the BG, BWFU and SH, respectively. In test,retest reliability coefficients, the coefficients for WTP for own nets were low-to-moderate at values of 0.51 (C.I. 0.40,0.62), 0.41 (C.I. 0.28,0.53) and 0.56 (C.I. 0.41,0.65) for the BG, BWFU and SH groups, respectively. Factors such as gender, change in income, unplanned expenditures, stated WTP in first survey, time-to-think, external information, and subjecting respondents to more than one interview explained the lower test,retest reliability coefficients. We conclude that the CVM was reliable in the study area and the question formats had similar levels of reliability. The lower coefficients in the test,retest reliability were due to the influence of factors affecting demand that had changed in the intervening period. Standard formats for determining reliability within CVM should be developed for easy comparison of results from different studies. Copyright © 2004 John Wiley & Sons, Ltd. [source]


Hematological parameters and anaerobic threshold in Brazilian soccer players throughout a training program

INTERNATIONAL JOURNAL OF LABORATORY HEMATOLOGY, Issue 2 2008
A. S. R. SILVA
Summary We assessed the responses of hematological parameters and their relationship to the anaerobic threshold of Brazilian soccer players during a training program. Twelve athletes were evaluated at the beginning (week 0, T1), in the middle (week 6, T2), and at the end (week 12, T3) of the soccer training program. On the first day at 7:30 am, before collecting the blood sample at rest for the determination of the hematological parameters, the athletes were conducted to the anthropometric evaluation. On the second day at 8:30 am, the athletes had their anaerobic threshold measured. Analysis of variance with Newman,Keuls'post hoc was used for statistical comparisons between the parameters measured during the soccer training program. Correlations between the parameters analyzed were determined using the Pearson's correlation coefficient. Erythrocytes concentration, hemoglobin, and hematocrit were significantly increased from T1 to T2. The specific soccer training program led to a rise in erythrocytes, hemoglobin, and hematocrit from T1 to T2. We assumed that these results occurred due to the plasma volume reduction and may be explained by the soccer training program characteristics. Furthermore, we did not observe any correlation between the anaerobic threshold and the hematological parameters. [source]


The psychometric properties of the Miller Behavioural Style Scale with adult daughters of women with early breast cancer: a literature review and empirical study

JOURNAL OF ADVANCED NURSING, Issue 2 2000
Charlotte E. Rees BSc PhD
The psychometric properties of the Miller Behavioural Style Scale with adult daughters of women with early breast cancer: a literature review and empirical study Several researchers have suggested that the information-seeking behaviours of patients need to be taken into consideration when assessing their information needs. This study reviews published evidence of the psychometric properties of the Miller Behavioural Style Scale, a tool commonly used to identify the information-seeking behaviours of individuals under threat, and examines its reliability and validity with adult daughters of women with early breast cancer. Ninety-seven adult daughters completed the MBSS and a 30-item, self-administered questionnaire, a tool designed to explore the information needs of adult daughters of women with breast cancer. The internal consistency of the monitoring and blunting sub-scales of the MBSS was ,=0·65 and 0·41 respectively. The blunting sub-scale fell substantially below acceptable limits and was discarded from subsequent analyses. The monitoring sub-scale possessed good test,retest reliability (n=17) with a 5-week time interval (r=0·71, P < 0·005), as measured using a Pearson's correlation coefficient. Furthermore, the majority (73·4%) of monitoring items possessed moderate or substantial test,retest reliability, as indicated by kappa coefficients. Finally, the monitoring sub-scale possessed good construct validity, both discriminant and convergent validity, as measured by the univariate associations between monitoring behaviour and selected items from the information questionnaire and a demographic questionnaire. In conclusion, adequate support exists for the psychometric properties of the monitoring sub-scale of the MBSS and its use with adult daughters of women with early breast cancer in future research. These findings have a number of implications for nursing research and these are discussed in this paper. [source]


Validity of an instrument to measure the impact of valve heart disease on the patient's daily life

JOURNAL OF CLINICAL NURSING, Issue 7 2007
Kátia Melissa Padilha RN
Aim., This study was to verify the psychometric properties of the Heart Valve Disease Impact on daily life, an instrument for measuring the impact of illness in the daily life of the heart valve disease patient, related to its construct validity, criterion-related validity and reliability. Methods., One hundred and twenty heart valve disease outpatients were enrolled. Data were submitted to descriptive analysis, factor analysis, Pearson's correlation coefficient and Cronbach's alpha coefficient. Results., The factor analysis generated four factors that explained 58% of the variance in response to the Heart Valve Disease Impact on daily life. Weak to moderate correlation was measured between the Heart Valve Disease Impact on daily life total score and two of its factors and the General Measure of Impact of illness, indicating criterion-related validity. A Cronbach's alpha of 0·74 was measured. Conclusion., The results of the current study confirm both the construct and criterion validity and the internal consistency of the Heart Valve Disease Impact on daily life. Future studies are necessary to confirm its reliability and provide a better understanding of the meaning of the Heart Valve Disease Impact on daily life dimensions, as well as to evaluate its response to health interventions. Relevance to clinical practice., The Heart Valve Disease Impact on daily life could be a useful instrument to measure the impact of heart valve disease and to evaluate the response to health interventions. [source]


Local biochemical markers of bone turnover: relationship to subsequent density of healing alveolar bone defects

JOURNAL OF CLINICAL PERIODONTOLOGY, Issue 3 2004
Richard A. Reinhardt
Abstract Objectives: This pilot study was designed to test whether biochemical markers of bone turnover in washes of periosteal or trabecular alveolar bone surfaces could be correlated with increases in bone density of an adjacent healing implant socket. Methods: Ten subjects had a canula inserted into the alveolar crest and sterile phosphate-buffered saline was washed over the periosteal and trabecular surfaces and collected. Surgical flaps were reflected, 5 mm diameter bone cores were removed from the bone wash site, and standardized radiographs were taken. The sites were allowed to heal for 12 weeks, and radiographs were repeated. Bone washes of the healing sites were also collected after 2 and 12 weeks. Washes were analysed for bone turnover markers osteocalcin (OC; radioimmunoassay) and C-terminal telopeptide of Type 1 collagen (ICTP; enzyme-linked immunosorbent assay (ELISA)), and blood component albumin (ALB; ELISA). Changes in bone density during healing were determined by radiographic absorptiometry. Results: OC/ALB and ICTP/ALB ratios were higher for trabecular than periosteal washes at baseline (p0.01). Trabecular OC/ALB and ICTP/ALB were inversely correlated with increasing bone density of the healing bone core socket (r=,0.72, p=0.03; Pearson's correlation coefficient). Conclusions: Biochemical markers of bone turnover in bone washes of specific alveolar bone sites may prove helpful in predicting how the bone density will increase around healing dental implants. [source]


Comparisons between a mixing ability test and masticatory performance tests using a brittle or an elastic test food

JOURNAL OF ORAL REHABILITATION, Issue 3 2009
T. SUGIURA
Summary, A variety of chewing tests and test items have been utilized to evaluate masticatory function. The purpose of this study was to compare a mixing ability test with masticatory performance tests using peanuts or gummy jelly as test foods. Thirty-two completely dentate subjects (Dentate group, mean age: 25·1 years) and 40 removable partial denture wearers (RPD group, mean age: 65·5 years) participated in this study. The subjects were asked to chew a two-coloured paraffin wax cube as a test item for 10 strokes. Mixing Ability Index (MAI) was determined from the colour mixture and shape of the chewed cube. Subjects were asked to chew 3 g portions of peanuts and a piece of gummy jelly for 20 strokes, respectively. Median particle size of chewed peanuts was determined using a multiple-sieving method. Concentration of dissolved glucose from the surface of the chewed gummy jelly was measured using a blood glucose meter. Pearson's correlation coefficient was used to test the relationships between the MAI, median particle size and the concentration of dissolved glucose. Mixing Ability Index was significantly related to median particle size (Dentate group: r = ,0·56, P < 0·001, RPD group: r = ,0·70, P < 0·001), but not significantly related to glucose concentration (Dentate group: r = 0·12, RPD group: r = 0·21, P > 0·05). It seems that ability of mixing the bolus is more strongly related to the ability of comminuting brittle food than elastic food. [source]