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PubMed1999

Social, emotional, and behavioral functioning of children with cancer.

OBJECTIVE: It was hypothesized that children with cancer would have more social problems and difficulties with emotional well-being than case control, same race/gender, similarly aged classmates. STUDY DESIGN: Using a case controlled design, children with any type of cancer requiring chemotherapy except brain tumors (n = 76), currently receiving chemotherapy, ages 8 to 15, were compared with case control classroom peers (n = 76). Peer relationships, emotional well-being, and behavior were evaluated based on peer, teacher, parent, and self-report, and were compared using analysis of variance and structural equation modeling. RESULTS: Relative to case controls, children with cancer were perceived by teachers as being more sociable; by teachers and peers as being less aggressive; and by peers as having greater social acceptance. Measures of depression, anxiety, loneliness, and self-concept showed no significant differences, except children with cancer reported significantly lower satisfaction with current athletic competence. There were also no significant differences in mother or father perceptions of behavioral problems, emotional well-being, or social functioning. Scores on all standardized measures were in the normal range for both groups. Comparisons of the correlation matrices of children with cancer and to the correlation matrix of the comparison children using structural equation modeling suggested they were not significantly different. CONCLUSIONS: Children with cancer currently receiving chemotherapy were remarkably similar to case controls on measures of emotional well-being and better on several dimensions of social functioning. These findings are not supportive of disability/stress models of childhood chronic illness and suggest considerable psychologic hardiness.

Adolescent↗

PubMedDate not supplied

Effect of nutrition status and other factors on length of hospital stay after major gastrointestinal surgery.

Various factors may prolong postoperative recovery and the length of stay (LOS) in the hospital. In a retrospective study of 245 adult patients who had no oral intake for 5 days after major gastrointestinal surgery, we used a correlation matrix to describe the population and determine the effects of the following factors on LOS: malnutrition, complication status, stress level, type of surgery, pathology, period of inadequate nutrient intake, and use of nutritional support. LOS was markedly prolonged in malnourished patients compared with those who were not (23.5 +/- 16.5 vs. 16.5 +/- 10.7 days, means +/- SD, p < 0.001). Patients were then grouped into those who had nutritional support and those who had not, and a nutrition classification was derived by examining the uncertainty (entropy) in the data matrix that allowed separation of the population into distinct groups. Nutrition and complication status and days without oral nutrient intake were discriminative. Analysis of variance and multivariate studies were also used to determine whether the presence of malnutrition, complications, both together, or neither could predict LOS and to determine the confounding effect of nutritional support on LOS. A significantly extended LOS persisted for patients with malnutrition or complications and was most prolonged for those with both, but patients who received nutritional support had a greater LOS than those who did not. In addition to the effects of nutritional support, malnutrition, and complication status, LOS correlated with the duration of the postoperative period without oral nutrient intake. We therefore recommend systematic and early nutritional intervention for selected gastrointestinal surgical patients.

Aged↗

PubMed1976

[Correlations between metric, cyto and histomorphological factors and thermographic findings in breast neoplasms].

Correlations between metric, cyto- and histomorphological characteristics and thermographical results of 119 carcinomas of the breast have been studied by statistical methods. For the purpose of semi-quantitative evaluation the chi2 of 14 characteristics were calculated from foursquare tables and summarized in a correlation matrix. The study revealed a significant increase of thermographically suspect pictures with increasing size, but this was independent of the depth (i.e. the distance from skin surface) of the tumors. The proportion of uncertain but not clearly suspect results was 35% with the infrared telethermovision method, in contrast to 8% with liquid crystal plate thermography. Thermographically non-suspect carcinomas (especially the negative cases with liquid crystal plate thermography) were rich in connective tissue or stroma in most cases. On the other hand, carcinomas with numerous mitoses, large cell nuclei, increased N/C-ratio and large and strongly stained nucleoli predominantly exhibited definitely suspect pictures. The significant correlation between number of mitoses, size and staining of nucleoli and the thermographic results emphasizes that, besides vascularization and altered thermo-regulatory functions, the metabolism of the tumor itself contributes to the temperature differences. The type of growth and histological grading indicate that tumors with unfavourable prognosis preferentially exhibit thermographically suspect results. The use of thermography as a screening method is restricted because of possible false negative results. On the other hand, its additional use is justified in view of the gain in information about the biological situation of suspect alterations of the breast.

Breast Neoplasms↗

PubMed1997

Correlations among size-related traits are affected by chromosome inversions in an adaptive polymorphism in Drosophila buzzatii.

Genetic variation in correlations among size-related traits of head, thorax and wings was examined in Drosophila buzzatii, by comparing the correlation pattern of the phenotypic correlation matrix (CP-Rp) between inversion karyotypes of the second chromosome. CP-Rp differed between some karyotypes in a natural population. CP-Rp in homokaryotypic classes of wild-reared flies, but not in heterokaryotypes, differed from the whole population represented by laboratory-reared flies. Similarity in CP-Rp was highly significant for a same homokaryotype in two populations. In one of them, the chromosome is polymorphic for four inversions. In the other population, one of the inversions is almost fixed. CP-Rp was significantly similar between these populations, illustrating that similarity of CP-Rp may even occur between populations which have greatly diverged in frequencies of some genotypes affecting correlation patterns. It is suggested that chromosomal inversions are factors affecting genetic correlations among traits known to be phenotypically correlated with fitness components.

Animals↗

PubMed2004

Clinical correlates of pain with amniocentesis.

OBJECTIVE: The purpose of this study was to determine whether sensory or affective dimensions of pain with genetic amniocentesis are associated with identifiable clinical correlates. STUDY DESIGN: Women completed the short-form McGill Pain Questionnaire after second-trimester genetic amniocentesis. The effect of maternal weight, parity, previous amniocentesis, previous surgery, history of menstrual cramps, maternal anxiety, presence of fibroid tumors, and depth and location of needle insertion on pain intensity was determined. The T-test, correlation matrix, Kruskal-Wallis test, and multiple logistic regression were used for analysis; a probability value of <.05 was considered significant. RESULTS: One hundred twenty-one women were enrolled: 19.3% reported no pain, 42.9% described the pain as mild, 31.1% described the pain as discomforting, and 6.7% described the pain as distressing or horrible. Mean intensity of pain was 1.6+/-1.3 (on a scale of 0-7). Pain was most often described as sharp, cramping, fearful, and stabbing. Anxiety and pain were increased in women with an indication of abnormal serum screen as compared with women with advanced maternal age. Anxiety and a history of menstrual cramps were associated with increased affective dimensions of pain and had moderate correlation with quantified pain intensity. A history of previous amniocentesis and needle insertion in the lower one third of the uterus were associated with increased pain. Maternal weight, parity, previous surgery, fibroid tumors, and depth of needle insertion were not correlated with perceived pain. Presence or absence of an accompanying person was not associated with pain intensity. CONCLUSION: Women report mild pain or discomfort with genetic amniocentesis. Increased pain is associated with increased maternal anxiety, a history of menstrual cramps, a previous amniocentesis, and insertion of the needle in the lower uterus.

Adult↗

PubMedDate not supplied

Psychological stress measure in type 2 diabetes.

Psychological stress has been implicated as a cause of several psychosomatic disorders, but also as a factor that can unfavourably influence many diseases including diabetes mellitus. Measure of psychological stress in diabetes was performed by Psychological Stress Measure (PSM), a validated instrument, designed using 49 items drawn from descriptors generated by focus groups on stress. Clinical and psychological framework was assessed in a cohort of 100 type 2 diabetic patients (30 m, 70 f), aged 66.99 +/- 13.68 years considering disease grade, complications and level of instruction. Three other questionnaires were administered concurrently to all patients: Sickness Impact Profile (SIP), Functional Living Index (FLI) and SF-36 QOL. ANOVA statistical testing and Spearman correlation matrix were used also vs socio-cultural and clinical profile. Gender, obesity, diet compliance, smoking do not affect PSM response. Hypertensive patients and those with family history of diabetes show lower PSM scores, according to a sort of moderator effect on stress of concurrent and/or previous experience with chronic disease. Neuromuscular ailments are more prevalent in women; men vs women experience severe limitations of their working capacities and relational possibilities, with severe discomfort. In the whole, higher scores of PSM (greater stress p < 0.01) and lower scores of FLI (fair well-being perception; p < 0.01) are reciprocally related inside any school instruction level. Despite the great reciprocal association of the PSM vs FLI and SIP, no significant correlation is found between PSM vs SF-36 QOL. Socio-cultural elements interfere, and particularly instruction level quantified as school grades achieved, with the manner of living their disease. Interventions on psychological distress of type 2 diabetes mellitus patients is warranted, specially in the groups with lower levels of instruction which may need an attentive strategy for achieving a satisfactory coping with this disease.

Aged↗

PubMed2002

Determination of some cationic species in temporary teeth.

Some cationic species (Ca, Mg, Sr, Cu, Zn and Pb) have been determined in temporary teeth (n = 67) sampled from a children population living in Mérida, Venezuela, with a mean age of 87.76 +/- 34.50 months within a range from 29 to 151 months. Each powdered tooth sample was analyzed for calcium, magnesium, strontium and zinc and for copper and lead by atomic absorption spectrometry with flame and electrothermal atomization, respectively. Relations between variables (elements concentration, age, sex, tooth type and caries status) were established using the Pearson correlation matrix and analysis of variance. The mean global concentrations were of 39.25 +/- 5.36; 1.08 +/- 0.81; 89.27 +/- 13.26 and 2.85 +/- 1.14 micrograms/g for Sr, Cu, Zn and Pb and of 208.45 +/- 33.18 and 8.51 +/- 2.05 mg/g for Ca and Mg, respectively. There were no changes in the teeth mineral content with respect to the children age and sex. With respect to the tooth type, there were significant differences only for strontium which varied in the order molars > canines > incisors. Although healthy teeth had higher mineral concentrations than carious teeth, there were not significant differences, proving that both, carious and healthy teeth could be used as indicators of mineral uptake. Magnesium and copper are the elements least related with the others. Significant positive correlations were found between Sr-Zn, Sr-Cu, Sr-Pb, and the only negative correlations were between Ca-Zn and Ca-Pb for the different types of teeth. While the positive association might indicate competition for anionic groups or similar affinity for the same sites in the crystalline structure, the negative correlations showed possible substitutions among the elements.

Aging↗

PubMed2005

Correlating structure with solute and water transport in a chronic model of peritoneal inflammation.

To study the process of chronic peritoneal inflammation from sterile solutions, we established an animal model to link structural changes with solute and water transport. Filtered solutions containing 4% N-acetylglucosamine (NAG) or 4% glucose (G) were injected intraperitoneally daily in 200- to 300-g rats and compared with controls (C). After 2 mo, each animal underwent transport studies using a chamber affixed to the parietal peritoneum to determine small-solute and protein mass transfer, osmotic filtration, and hydraulic flow. After euthanasia, parietal tissues were sampled for histological analysis, which demonstrated significant differences in peritoneal thickness (microm; C, 42.6 +/- 7.5; G, 80.4 +/- 22.3; NAG, 450 +/- 104; P < 0.05). Staining for VEGF correlated with CD-31 vessel counts (no./mm2: C, 53.1 +/- 16.1; G, 166 +/- 32; NAG, 183 +/- 32; P < 0.05). Tissue analysis showed treatment effects on tissue hyaluronan (micro/g: C, 962 +/- 73; G, 1,169 +/- 69; NAG, 1,428 +/- 69; P < 0.05) and collagen (microg/g: C, 56.9 +/- 12.0; G, 107 +/- 12; NAG, 97.6 +/- 11.4; P < 0.05) but not sulfated glycosaminoglycan. Transport experiments revealed no significant differences in mannitol transfer or osmotic flow. Changes were seen in hydrostatic pressure-driven flux (microl x min(-1) x cm(-2): C, 0.676 +/- 0.133; G, 0.317 +/- 0.124; NAG, 0.284 +/- 0.117; P < 0.05) and albumin transfer (microl x min(-1) x cm(-2): C, 0.331 +/- 0.028; G, 0.286 +/- 0.026; NAG, 0.229 +/- 0.025; P < 0.04). We conclude that alteration of the interstitial matrix correlates with diminished hydraulic conductivity and macromolecular transport.

Abdominal Wall↗

PubMedDate not supplied

The Functional Pain Scale: reliability, validity, and responsiveness in an elderly population.

OBJECTIVES: Because of difficulty experienced in assessing pain in frail older patients and the lack of pain assessment tools with standardization in the elderly, the Functional Pain Scale (FPS), an instrument incorporating both subjective and objective components to assess pain, was developed and evaluated. DESIGN, SETTING, PARTICIPANTS, AND MEASURES: One hundred subjects more than 65 years old participated in the validity, reliability, and responsiveness (the clinical sensitivity of the instrument to change) testing of the Functional Pain Scale. Subjects were recruited from a geriatrics inpatient setting, a geriatrics outpatient setting, and a local hospice (residing in their homes). Ninety-four of the subjects completed all phases of testing. Reliability was tested using a test-retest format and a correlation matrix. Criterion-related validity was established as compared with the Visual Analog Scale (VAS), the Present Pain Intensity (PPI), the McGill Short Form Questionnaire (MPQ-SF), and the Numeric Pain Scale (NPS) instruments. Responsiveness for the FPS, the VAS, the PPI, the MPQ-SF, and the NPS instruments was determined using five previously described techniques: effect size, standardized response means, relative efficiency, direct comparison of t test scores, and direct comparison of P values. A cumulative index was developed to rank each scale. Cumulative responsiveness index scores were based on individual scale performance for each separate responsiveness test. The lowest score in the cumulative responsiveness index indicated the most responsive scale. RESULTS: Interrater reliability for instruments tested exceeded 0.95 for all instruments tested. Validity testing showed high correlations as well (r = 0.62, r = 0.85, r = 0.80, r = 0.90 for the VAS, the PPI, the MPQ-SF, and the NPS respectively). Responsiveness evaluated overall by the responsiveness index was best for the Functional Pain Scale (7) followed by the Visual Analog Scale (12), the Present Pain Intensity (13), the McGill Pain Questionnaire-Short Form (19), and the Numerical Pain Questionnaire (24). CONCLUSIONS: The Functional Pain Scale was determined to be reliable, valid, and responsive. The responsiveness of the Functional Pain Scale was superior to the other instruments tested. The Functional Pain Scale is an acceptable instrument for assessing pain in older adults and may reflect changes in pain better than other instruments tested. Further testing in other populations is warranted.

Journal Article↗

PubMed2001

Factor analysis of asthma and atopy traits shows 2 major components, one of which is linked to markers on chromosome 5q.

BACKGROUND: A variety of definitions of asthma and atopy traits have been used in genetic studies. The variables used may be correlated, increasing the likelihood of type I error. OBJECTIVE: We sought to clarify and quantify phenotypes that may be characterized by related traits. Principal components and factor analysis were applied to the correlation matrix of asthma and atopy traits before linkage analysis. METHODS: Factor analysis was performed on 468 Hispanic and non-Hispanic white children enrolled in the Tucson Children's Respiratory Study, with complete information on 24 items, including skin test response to 7 allergens, total serum IgE levels, presence or absence of asthma attacks, wheezing episodes, hay fever, and cough. Factor score coefficients were then applied to all siblings (n = 877), and quantitative factor scores were derived. Single-point and multipoint nonparametric sib-pair analyses were performed to assess linkage to markers on chromosome 5q31-33. Analyses were also performed for individual items. RESULTS: Two main factors were identified: Factor I had high loadings on atopic items, including skin test responses, IgE, and hay fever, and Factor II had high loadings that included asthma diagnosis, wheezing, cough, and Alternaria species skin test response. Factors I and II were correlated at an r value of 0.19. For the quantitative factor scores, significant single-point linkage (P < .0001) was demonstrated only for atopic Factor I, and a peak multipoint LOD score of 2.7 was seen for marker D5S479. Multipoint LOD scores for individual items were 1.1 or less. CONCLUSION: These analyses suggest evidence for a locus or loci mapping to chromosome 5q31-33 associated with this composite atopic phenotype.

Asthma↗

PubMed1996

Using factor analysis to explore nurses' fear of AIDS in the United States of America.

The purpose of this study was to create a reliable research instrument to test the fear of AIDS (FOA) and to explore the dimension of FOA among nurses. We hypothesized that certain factors, such as physical closeness to AIDS patients or HIV-positive blood and nontolerance of homosexuals, increase fear of AIDS among nurses. A sample of 365 nurses in a mid-Atlantic state of the United States was surveyed with an 82-item Knowledge, Attitudes, and Practice (KAP) questionnaire to examine the fear of AIDS among nurses in the United States. Using correlation, item and factorial analysis, a 23-item FOA Scale II (alpha = 0.826) was created and seven FOA factors were identified. Factor analysis was used to help understand the dimensions of FOA as measured by FOA Scale II. Principal components analysis was used to analyse the correlation matrix because some items were on a five-point scale and some were on a three-point scale. The varimax rotation was used, because if one were to define dimensions then these dimensions should be as independent of each other as possible. The coefficient alpha of 0.826 obtained from using FOA Scale II indicated that FOA could be considered to be a general factor; but the general factor could be exhibited through several avenues. It was determined that FOA could be represented by four or by seven dimensions, and if one uses the eigenvalue of 1 for a cut-off point then one would argue that there were seven factors. If one used the screen test, then one could assume that there were four factors of interest. Our decision for the analysis of this paper was to attempt the interpretation of the seven factors. We used both the factor loadings-the correlation of the item score with the linear combination-and the factor score coefficients (the weights of the items to form the linear combinations) to interpret the factor. The factor analysis thus seems to give insight into the dimensions of FOA as measured by FOA Scale II. Fear of AIDS seems to be exhibited in the following seven ways: (a) support for policies which would protect me from AIDS, (b) fear of contact with blood and bodily fluids of AIDS patient, (c) turning against those who have AIDS, (d) only care for those who deserve to be helped, (e)concern that I would have no help if I had AIDS, (f) concern about the financial burden of AIDS, and (g) loss of self-worth for one who has AIDS.

Acquired Immunodeficiency Syndrome↗

PubMed2006

Use of multivariate analysis to extract latent variables related to level of production and lactation persistency in dairy cattle.

Multivariate factor analysis and principal component analysis were used to decompose the correlation matrix of test-day milk yields of 48,374 lactations of 21,721 Italian Simmental cows. Two common latent factors related to level of production in early lactation and lactation persistency, and 2 principal components associated with the whole lactation yield and persistency were obtained. Factor and principal component scores were treated as new quantitative phenotypes related to prominent features of lactation curve shape. Genetic parameters were estimated by univariate and bivariate animal models. Estimates of heritability were moderately low for both latent factors (0.13 for persistency and yield early in lactation). Heritabilities of the principal component related to total lactation yield and 305-d yield were similar (0.19 and 0.20, respectively). Finally, heritability was quite low for the principal component related to lactation persistency (0.07). Repeatabilities between lactations were about 0.27 for both latent factors, around 0.4 for the first principal component and 305-d yield, and 0.11 for the second principal component. Moderate genetic correlation among common factors (0.26) and their high genetic correlation with total lactation yield (>0.60) suggest that selection can be used to change the shape of lactation curve as well as improve yield. Scores of the second principal component can be used to genetically improve persistency while maintaining constant total lactation yield.

Analysis of Variance↗

PubMed2003

Partitioning large-sample microarray-based gene expression profiles using principal components analysis.

Principal components analysis (PCA) is useful for reproducing the total variation among hundreds or thousands of continuously-scaled variables with a much smaller number of unobservable variables called 'latent factors'. The CLUSFAVOR computer program was used to implement PCA for identifying groups of genes with similar expression profiles from a large number of genes used on DNA microarrays. This paper describes the principal components solution to the factor model of the correlation matrix R, calculation of eigenvalues and eigenvectors of R, extraction of factors, and calculation of factor loadings and identification of genes with similar loading patterns to construct groups of genes with similar expression profiles. With regard to extraction of factors, it was found that more than 90% of the total variance in input data could be accounted for by extracting factors whose eigenvalues exceed unity. Bipolar factors containing strong positive and negative loadings can also be used for identifying two unique groups of genes, since expression profiles of genes that load positive are unlike expression profiles of genes that load negative on the same factor. While PCA does not provide the absolute answer to a multidimensional problem, it nevertheless can provide a heuristic with which natural groupings of genes with similar expression profiles can be assembled. While cluster analysis essentially generates a single dendogram (tree branch) containing every gene in the input data, PCA can be used to assemble gene expression profiles that strongly correlate with the latent factors accounting for a majority of total variance. Example results for CLUSFAVOR computer program runs are provided.

Gene Expression Profiling↗

PubMed1997

Group sequential monitoring of distribution-free analyses of repeated measures.

In many clinical trials the principal analysis consists of a 1 degree of freedom test based on an aggregate summary statistic for a set of repeated measures. Various methods have been proposed for the marginal analysis of such repeated measures that entail estimates of a measure of treatment group difference (the treatment effect) at each of K repeated measures and a consistent estimate of the covariance matrix, where asymptotically these estimates are normally distributed. One can then obtain an overall large sample 1-d.f. test of group differences, such as by taking the average of these K estimates. These methods include the Wei-Lachin family of multivariate rank tests and a corresponding multivariate analysis using the Mann-Whitney difference estimator as a measure of treatment group differences. Other methods, such as O'Brien's non-parametric test, are based on a single summary score for each patient, such as the within-patient mean value. These, and other such methods, allow for some observations to be missing at random. Herein I employ sequential data augmentation to conduct group sequential analyses using a 1 degree of freedom test from a multivariate Mann-Whitney analysis and for the O'Brien rank test. Su and Lachin used this method to perform group sequential analyses of a vector of Hodges-Lehmann estimators. By augmentating the data from the sequential looks in a single analysis, one obtains an estimate of the covariance of the estimates at each look, from which one obtains an estimate of the correlations among the sequential 1-d.f. test statistics. I describe a simple secant algorithm to determine the group sequential boundaries based on recursive integration of the standard multivariate normal distribution with the estimated correlation matrix. Although the boundary obtains readily using the method of Slud and Wei, the more flexible method of Lan and DeMets may be preferred. The true information fraction at each look, needed to apply the spending function method of Lan and DeMets, however, is unknown. Thus, I also describe the use of a surrogate measure of information.

Algorithms↗

PubMedDate not supplied

[French validation study of the levels of emotional awareness scale].

According to a thesis based on the idea of an influence of cognitions in the structuring of internal reality, emotional awareness, ie the capacity of representing your own emotional experience and that of others, is a cognitive process that goes into maturation. Defining this concept, Lane and Schwartz present a cognitivo-developmental model in five stages of the processes of symbolization, accounting for the differences in levels of emotional awareness observed in individuals. The organization of these cognitive processes would thus be structured in well differentiated stages, in which the development of the emotions would be inseparable from the development of ego and of the relation to others. These authors focus on the capacity of representing in a conscious way the emotional experience and consider that verbal representations used to describe the contents of what is experience constitute a good reflection of the organization structural of the emotional awareness. Therefore, they worked out an instrument of evaluation: the Levels of Emotional Awareness Scale (LEAS), which measures the capacity to describe your own emotional experience and the one you allow to others, in an emotional situation. The system of quotation of this scale is based on the analysis of the verbal contents of the provided answers, in direct reference to the authors' theory of the levels of differentiation and integration of the emotional experience. It is therefore an empirical measurement which is centered specifically on the structural organization of the emotional experience. The various studies of validation of this instrument show that it presents solid metrological properties. This work presents the validation of the French version of Lane and Schwartz's LEAS. Validity and fidelity were studied in a group of 121 healthy subjects. This setting is part of a larger clinical evaluation, also including a collection of socio-demographic and clinical data, and other instruments of self-evaluation (Beck Depression Inventory, BDI, Hospital Anxiety and Depression Scale, HAD, and Toronto Alexithymia Scale, TAS). The face validity appears correct: the questionnaire was well accepted and seemed easy to complete. A principal components analysis of the correlation matrix of the set of items was used as the method of extraction of the various factors and made it possible to confirm the unidimensionality of the instrument. The number of factors to be retained was given according to Kaiser and Cattell criteria. The internal consistency was evaluated through computation of the Cronbach coefficient, whose value is 0.75 for the scale's global score. The confidence interval of the margin of error of LEAS scores was also measured; for the global score it is IC=[m 6.1]. The measure given by this rating scale may therefore be considered sufficiently accurate, since this interval is weak. A study of the frequency of quotation of each item of the instrument was carried out, in order to check the homogeneity and the uniformity of quotations, as well as a diagram of distribution of the score, showing that it follows a law which is close to a normal law. The concurrent validity could only be studied via the similar concept of alexithymia, measured with the TAS, for there is not other instrument validated in French evaluating the levels of emotional awareness, and these two instruments seem to measure different notions, because none of the correlations between the scores of these two questionnaires are significant. Concerning discriminant validity, the Pearson correlation coefficients between the global score for the LEAS, the BDI score and the HAD sub-scores for depression and anxiety were measured; it is clear that the level of emotional awareness is independent from negative affects. Furthermore, the study of the reliability made it possible to highlight excellent intra-class correlation coefficients (r=0.993). The French version of the Levels of Emotional Awareness Scale thus appears to be valid and accurate and should allow the study of levels of emotional awareness on psychopathology. It is about an easily acceptable and simple questionnaire of use in varied clinical circumstances.

Adolescent↗

PubMed2001

Analysis of the performance characteristics of the University of Washington Quality of Life instrument and its modification (UW-QOL-R).

BACKGROUND: During a 5-year period, we analyzed 3 patient subsets from the University of Washington Quality of Life (UW-QOL) Registry and published the results. In each instance, editorial review has raised legitimate concerns regarding the UW-QOL instrument that deserve public comment. We present our response to these criticisms. Since our original publication (1993), we have added domains to the original UW-QOL instrument. These additions reflected our concern that we might be missing important elements in the spectrum of disease-specific response to treatment. Using the data we have accumulated in the last 5 years, we present an analysis of the internal consistency of the UW-QOL. We have identified those domains that are responsive (or not responsive) to treatment effect and have revised the UW-QOL accordingly to create the UW-QOL-R, which is recommended for future use. DESIGN: The project began January 1, 1993, after approval by the UW Human Subjects Committee. Critical comments offered by external review were collated and responded to. Internal consistency was evaluated by interitem correlation matrix (Cronbach alpha) testing. SUBJECTS: All new patients presenting to the UW Medical Center (Seattle) with a diagnosis of head and neck cancer were asked to participate in a prospective analysis of QOL changes during and after treatment. INTERVENTION: Patients completed the pretreatment QOL questionnaire on the day of their initial workup. The format for the pretreatment test was an interviewer-supervised self-administered test; the subsequent tests were self-administered and were completed at 3, 6, 12, 24, and 36 months. Other data entered for each patient included site, stage, treatment, histologic classification, reconstruction, and current status. A QOL registrar was responsible for patient follow-up, data collection, and collation. All data were entered into the departmental relational database. RESULTS: Criticisms by external review included the following: "it is improper to call it [UW-QOL] a measure of quality of life"; "the summary scale is problematic because it implies that each of the subscales are weighted or 'valued' equally"; "some domain questions relate to surgery specific issues. while others are specific to radiation"; "we were confused by the scoring"; and "the UW-QOL index does not specifically address the psychological impact of the disease and its treatment." After evaluation of internal consistency, the UW-QOL was modified by removing 2 domains that correlated poorly with the others. This resulted in a 10-item instrument (UW-QOL-R) with an overall internal consistency score of 0.85. CONCLUSIONS: The UW-QOL can be effectively and accurately used to compare treatment effects in the management of head and neck cancer. With this revised instrument, the 10 items appear to measure the domains of overall QOL in a highly consistent and reliable fashion over time.

Head and Neck Neoplasms↗

PubMed2004

Random matrix theory analysis of cross correlations in financial markets.

We confirm universal behaviors such as eigenvalue distribution and spacings predicted by random matrix theory (RMT) for the cross correlation matrix of the daily stock prices of Tokyo Stock Exchange from 1993 to 2001, which have been reported for New York Stock Exchange in previous studies. It is shown that the random part of the eigenvalue distribution of the cross correlation matrix is stable even when deterministic correlations are present. Some deviations in the small eigenvalue statistics outside the bounds of the universality class of RMT are not completely explained with the deterministic correlations as proposed in previous studies. We study the effect of randomness on deterministic correlations and find that randomness causes a repulsion between deterministic eigenvalues and the random eigenvalues. This is interpreted as a reminiscent of "level repulsion" in RMT and explains some deviations from the previous studies observed in the market data. We also study correlated groups of issues in these markets and propose a refined method to identify correlated groups based on RMT. Some characteristic differences between properties of Tokyo Stock Exchange and New York Stock Exchange are found.

Journal Article↗

PubMed1997

Fueguian cranial morphology: the adaptation to a cold, harsh environment.

Craniometric data from the three extinct tribes that inhabited Tierra del Fuego (Selk'nam, Yámana, and Kawéskar) were gathered following Howell's measurement technique. We studied 180 skulls preserved at thirteen different institutions. Analysis of variance (ANOVA) between groups showed that morphological similarities among Fueguian groups are far more important than some differences between marine (Yámana and Kawéskar) and terrestrial (Selk'nam) groups. A principal component analysis (PCA) generated from the correlation matrix shows that Fueguians fall as outliers with respect to the typical Mongoloid morphology. In addition, a UPGMA tree generated from a squared Euclidean distance matrix indicates that Fueguian groups have a morphological pattern that is very distinct from that of other present-day Amerindian groups, with the exception of the Eskimos. One of the variables that contributes substantially to the differentiation of Eskimos and Fueguians is the nasal height. This suggests that nasal morphology in both groups could be a response to adaptive pressures related to the cold environment. However, other morphological particularities of Fueguian skulls, such as craniofacial robustness and variables of craniofacial width, can be attributed to a large masticatory stress. As a whole, the morphological features of Fueguian groups can be regarded as a general adaptive response to a very harsh environment, along with the retention of some plesiomorphic features. Assuming that the initial entry in Tierra de Fuego took place around 10,000 years BP, before the disappearance of the last land bridges in the Magellan Straits, then this adaptation might have arisen in a relatively short period, hastened by the extreme environmental conditions.

Adaptation, Physiological↗