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This study investigated the relationships between assessments of competence as supplied by clinical faculty and examination performance on the 1975 Cardiovascular Disease subspecialty examination. Canonical correlation analysis showed the existence of two factors, which accounted for 36% of the variance in common.
This paper presents empirical results concerning the interdependency of somatic and psychological factors in the course of Crohn's disease. Data derived from the Heidelberg psychosomatic study on Crohn's disease are explored with the help of canonical correlation analysis. Somatic data recorded in the acute stage of Crohn's disease were not empirically found to be predictive of the psychological status after convalescence empirically. On the other hand, we did find psychological data that allowed prediction of the somatic status when the patients were in remission. Of these psychological data, coping resources are the most important predictors of the course of the disease. In particular, depressive forms of coping are correlated with personality factors, whereas active coping forms are not. The results have implications for scientific theory as well as for clinical practice.
Concentrations of the products of peroxide oxidation of lipids (POL), indices of the system of antioxidant defence (SAD), and the activity of 13 diagnostically significant organic/tissue specific enzymes (DSE) were determined in blood serum of cosmonauts who had participated in short (5-9 days, n = 8), long (125-179 days, N = 15), and superlong (241-366 days, n = 5) missions. To feature an interrelation of the indices under study, the canonical correlation analysis of a set of POL and SAP parameters and DSE activity was performed. Compared with pre-flight values, changes in the POL and SAP parameters were significant in serum only after the long-duration missions. Signs of POL activation were noted following the superlong missions. After the long-duration missions increased was the activity (mainly, within the norm) of DSEs, specific for the organs and tissues functioning of which is stressed in the period of post-flight readaptation (skeletal muscles, myocardium, liver). After the superlong missions, the DSE activity either remained essentially unchanged or decreased. In all the tested groups, highly reliable correlations between POL, SAP, and the DSE activity, traditionally applied in clinical diagnostics, were observed. These advocate for the use of POL and SAP indices in medical diagnostics and prognosis of cosmonauts' health.
Some physique-behavior relations were determined in 75 boys and 51 girls, aged 6 to 14, in a residential treatment center in Holland. Each child's behavior was rated by four group workers on a checklist yielding eight summary scores. Physique was judged from nude photographs for manifest endomorphy, mesomorphy, and ectomorphy. While a number of moderate-sized relations appeared in zero-order and multiple correlations, canonical analysis showed two significant, independent sets of relations between physique and behavior in the boys, one in the girls. Among the boys, one set related mesomorphy and energy level, the other related primarily ectomorphy with unsocialness, excitability, and cooperativeness. Among the girls, these same behaviors were compressed in a single set, primarily relating energy level but also unsocialness, excitability, and cooperativeness positively with mesomorphy and negatively with endomorphy and ectomorphy. Compared with findings on the same instrument in a sample of normal American preschoolers, many individual associations were similar, despite differences in culture and language, age, intelligence, social status, adjustment, and residential setting of the S's.
An atherometric system (AS) was used to study coronary atherosclerotic lesions of a sample of 73 autopsy subjects. The content of nine chemical elements in the hair (K, Ca, Zn, Br, Sr, Pb, S, Cl, Cu) and the rates Zn/Cu and Ca/K were determined by energy dispersive X-ray fluorescence (EDXRF) analysis. Some canonical correlation analyses (CCA) were made of different combinations of chemical elements contents and of the following descriptive arterial variables of As: fatty streaks, fibrous plaques, severe (complicated plus calcified), plaques, and total atherosclerosis and the three weighted indices of AS, i.e. obstruction, stenosis and benignity. The arterial variables were obtained from the three major epicardial branches of the coronary arteries. Similar CCA analyses were performed to correlate chemical elements of the hair with some heart variables of AS, such as heart weight and estimated total volume of myocardium damaged by fibrosis and/or necrosis. The most remarkable results were as follows: Combinations of Pb, Ca/K, Zn/Cu and Fe, Ca/K, Zn/Cu were always strongly correlated with fatty streaks, fibrous plaques and severe plaques of the three coronary artery branches and the total coronary artery system, with the only exception of the left circumflex coronary artery when Fe was included. Similar results were recorded from obstruction, stenosis and benignity indices of AS. These two combinations of chemical elements were also correlated with the heart variables of AS. When the group of elements was integrated by Br, Ca/K, Zn/Cu, there were significant results with the heart variables, but not with the arterial variables of the AS.
In this paper, field experiment was conducted to analysis the canonical correlations of light and temperature with the yield and quality characters of F1 ecological populations of 54 hybrid rice breeds. The results showed that the yield and quality characters of the populations were significantly correlated with the accumulated temperature, effective accumulated temperature, extreme temperature difference, and sunshine length through the growth period of hybrid rice. The first canonical correlation coefficient (lambda1) between the light and temperature during vegetative growth stage and the yield characters was 0.9975, with the canonical information accounted for 99.96% of the total canonical information, leading to 99.50% of yield variation. Light and temperature affected the yield of hybrid rice mainly through their effects on the total and effective numbers of grains' spikelet and its fertility. In this aspect, accumulated and effective accumulated temperature played a determinative role during vegetative growth stage, while extreme temperature difference and sunshine length were the key factors during reproductive growth stage. As for the quality characters of hybrid rice, light and temperature mainly affected the percentage of polished to head rice, and in this aspect, accumulated and effective accumulated temperature played a determinative role before filling stage, while extreme temperature difference and sunshine length were the key factors after this
This paper describes a novel method using maximum entropy principle introduced by Shannon to construct a unique integrated character and gives a comparison between this method and multivariate statistics in quantitative genetics. In multivariate genetic analysis multivariate statistics is usually used for a polygenic system of multiple quantitative traits to form several complex character. Genetic analysis can be implemented through treating these correlated elementary traits by using the technique of principal component analysis or canonical correlation. Differing from the multivariate statistics, this paper presents a new method using maximum-entropy principle to obtain a unique integrated character from a set of correlated quantitative traits. This method has the advantages of simple mathematical structure and process, simple and clear results.
OBJECTIVES: Chronic respiratory diseases may alter a patient's social life and well-being. Measures of health-related quality of life have been proven to bring complementary information to functional assessments. The aim of the study was to describe the questionnaires that are most frequently used to measure this subjective construct in patients with chronic obstructive pulmonary disease (COPD) and to compare the responses obtained via administering one generic (SF-36) and one disease-specific questionnaire (St. George's Respiratory Questionnaire; SGRQ) to patients with COPD. METHODS: One group of patients (46 individuals) was used to evaluate the questionnaire's performance in repeated administrations under unchanged conditions (reproducibility) and to study the correlations of corresponding domains of respective questionnaires. Responsiveness of both questionnaires was tested on another group of 129 patients measured before and after the therapeutic stay at the spa. Methods of correlational analysis (Spearman, intraclass, and canonical correlation coefficients) as well as the Wilcoxon rank test were used for statistical analysis. RESULTS: Both questionnaires seem to be comprehensive outcome measures for patients with COPD, but some particular areas may not be covered with the same intensity (e.g. emotional problems). Reproducibility of both questionnaires was good and only small non-significant shifts were seen, particularly in physical and social functioning domains. In repeated measurement, the SGRQ seemed to be slightly more responsive to change than the SF-36. CONCLUSIONS: The idea of using generic and disease-specific questionnaires together probably represents the best approach to this topic. It may improve our knowledge and explain better the relationship between disease-specific changes in patient status and both disease-specific treatment and general functional status.
Test results (raw scores) are composed of an unknown true score and an error term. The error term can be estimated by means of test reliability which is defined by the ratio of true variance and obtained variance. Different estimates of reliability either based on single measurements (e. g. Cronbach's coefficient, split half reliability, Kuder Richardson method) or two measurements (test/retest, inter- or intrarater reliability) are available. Parallel test reliability depends on the correlation of two different tests obtained in one session. Canonical correlation methods allow an extension of the parallel test situation and split half technique. Two or more tests are performed in a sample of subjects. Randomized subsets are correlated using canonical correlation technique. The objective of this study is to estimate the homogeneity of test batteries. 94 patients (64 f, 30 m; age: 54 - 89 ys.) supposed to have dementia were tested using the clocktest (CT, scores: 1 - 5), MMSE (mini mental state examination) and SKT (Syndrom Kurztest). Four (i, j: 1 - 4) subsets of 20 patients each were determined by random and the following characteristics were calculated: Empiric correlation coefficient for n = 94 (R), canonical correlation coefficient (Rcan), eigenvalues (EV) and redundancy (Rnd) of corresponding variable sets. The results of canonical analysis showed canonical correlation coefficients in order of 0.8 to 0.9 (p-values < 0,001). This high internal consistency can be interpreted as a measure of reliability of the test batteries. In conclusion, canonical correlation based on parallel tests splitted in subsets gives information on consistency, i. e. reliability, of test batteries in addition to conventional correlation methods.
Test results (raw scores) are composed of an unknown true score and an error term. The error term can be estimated by means of test reliability which is defined by the ratio of true variance and obtained variance. Different estimates of reliability either based on single measurements (e.g. Cronbach's coefficient, split half reliability, Kuder Richardson method) or two measurements (test/retest, inter- or intrarater reliability) are available. Parallel test reliability depends on the correlation of two different tests obtained in one session. Canonical correlation methods allow an extension of the parallel test situation and split half technique. Two or more tests are performed in a sample of subjects. Randomized subsets are correlated using canonical correlation technique. The objective of this study is to estimate the homogeneity of test batteries. 94 patients (64 f, 30 m; age: 54-89 ys.) supposed to have dementia were tested using the clocktest (CT, scores: 1-5), MMSE (mini mental state examination) and SKT (Syndrom Kurztest). Four (i, j: 1-4) subsets of 20 patients each were determined by random and the following characteristics were calculated: Empiric correlation coefficient for n = 94 (R), canonical correlation coefficient (Rcan), eigenvalues (EV) and redundancy (Rnd) of corresponding variable sets. The results of canonical analysis showed canonical correlation coefficients in order of 0.8 to 0.9 (p-values < 0.001). This high internal consistency can be interpreted as a measure of reliability of the test batteries. In conclusion, canonical correlation based on parallel tests splitted in subsets gives information on consistency, i.e. reliability, of test batteries in addition to conventional correlation methods.
The Multidimensional Scale of Independent Functioning (MSIF) is a new instrument for rating functional disability in psychiatric outpatients. The MSIF differs from other disability rating scales by providing discrete ratings of (1) role responsibility, (2) presence and level of support, and (3) performance quality. The MSIF, which consists of a semistructured interview and detailed rating anchors, was validated in 114 psychiatric outpatients. The instrument had good criterion, discriminative, interrater, and construct validity. Correlations between comparable ratings on the Social Adjustment Scale II (SAS II) ranged from 0.78 to 0.86. Nevertheless, redundancy analysis using canonical correlation demonstrated that, although the two instruments overlap, the MSIF contains information that is not contained in the SAS II. Furthermore, there was only modest shared variance with conceptually non-overlapping subscales in the SAS II. Interrater reliability (intraclass correlation coefficients) ranged from 0.74 to 1.00 for global and subscale scores. MSIF subscales performed as expected with respect to external validators such as hours of employment, earned income, supported versus nonsupported employment and housing, and mainstream versus nonmainstream educational status. MSIF global ratings were modestly correlated with IQ and psychopathology ratings, consistent with reports in the literature. Construct validity, estimated using Cronbach's alpha coefficient, was 0.72. The MSIF is a promising new instrument designed to circumvent several limitations with existing functional outcome instruments for longitudinal studies, intervention research, and services research.
In order to identify associations between the orientation of the superficial masseter and temporalis muscles and dentoskeletal morphology in a sample of fifty-five children with various malocclusions, eight muscle-orientation variables (relative to the occlusal plane) and twenty-three dentoskeletal variables were evaluated from lateral head films. The thirty-one measurements were reduced to six muscle-orientation and sixteen dentoskeletal variables by a principal component analysis. Three canonical correlations were identified between the muscle orientation and dentoskeletal variable groups at the 0.05 level of significance and canonical loadings were determined for each set of variables. The first canonical correlation (r1 = 0.931) represents a growth-related correlation factor between the masticatory muscle insertion positions relative to the occlusal plane and the dimensional and positional changes of craniofacial structures during growth. The second canonical correlation (r2 = 0.846) may account for an operational artifact in the geometric measurement process, and the third canonical correlation (r3 = 0.813) suggests an association between superficial masseter muscle orientation relative to the occlusal plane and mandibular form. This report confirms the usefulness of multivariate statistical methods to extract latent associations between muscle orientation and craniofacial morphology; the results obtained suggest a contribution from the geometric orientation of the masticatory muscles to the development and maintenance of the dentoskeletal system.
This study reports of a further analysis on the data presented in a previous work. The intention of the present study was to analyse exhaustively the relationship between some social and demographic variables with some aspects of attempts to suicide. The variables for this study were chosen on the basis of the completeness of data. Sex, age, single vs. married, and family relationship of the subjects were the predictive variables; the aspects of attempts to suicide considered were: number, kinds, means, and motives of attempts. An analysis of canonical correlation failed to show clearly any common relationship of the demographic variables in regard to the aspects of attempts to suicide. In fact, the first group of covariates resulted in a correlation of .40 whose chi square was 22.16 for a p less than .10. However, an univariate analysis of multiple regression for each of the four aspects of attempts to suicide over the four demographic variables showed that a) age of subjects has a definite relationship with the motives to commit suicide, that is, with age; the motives to attempt suicide change predominantly from family difficulties to problems of a more social and professional character; b) also, it was observed a generalized tendency on the part of male subjects to show attempts to suicide of a more serious nature, namely, they plan their attempts and make use of means of a more lethal nature (poison instead of simple drugs). However, it must be noted that the male sample was older than the female, making it hard to decide in this case whether age or sex of the subjects would be the best predictor.
A number of instruments are used to measure Orem's (1985) concept of self-care agency. Their use reflects basic assumptions that both the instrument and the underlying tenets of the theory are valid. The purpose of this study was to examine the latent traits associated with three instruments designed to measure self-care agency. These included Denyes' (1980) Self-Care Agency, Kearney and Fleischer's (1979) Exercise of Self-Care Agency, and Hanson and Bickel's (1985) Perception of Self-Care Agency. The convenience sample consisted of 513 adult, nonhospitalized subjects who completed the three instruments. Common factor analysis and canonical correlation were used to identify latent traits and their relationships. The findings support the multidimensionality of Orem's (1985) concept of self-care agency. However, the use of one instrument does not adequately reflect this multidimensionality.
The study explored associations between the cerebral event-related slow potentials (ERSP) and psychiatric symptoms and syndromes as reflected by the Present State Examination (PSE) in 36 randomly selected psychiatric in-patients. Independent raters measured the readiness potential (RP), contingent negative variation (CNV) and post-imperative negative variation (PINV) in terms of their amplitude and duration. The 360 individual PSE items were grouped into units of analysis (UA) and further collapsed into groups of units of analysis (GUA). Canonical correlations were computed between two sets of variables (psychological and electrophysiological). Kendall's rank-order correlation was used as the main statistical approach. Some psychotic signs were associated with increased PINV amplitude. Obsessive thoughts, ideas of reference and verbal hallucinations correlated with longer PINV duration. Hopelessness and suicidal thoughts (affect-laden thoughts) as well as first-rank Schneiderian symptoms (FRS) were negatively correlated with CNV amplitude. The results support the hypothesis that CNV and PINV, alone or in combination, can be used to indicate the presence or absence of identifiable psychiatric symptoms and syndromes. The implications of electrophysiological correlates of psychopathology for psychiatric nosology and for the validity of psychiatric symptoms and syndromes were discussed.
Longitudinal analysis with generalized estimating equation (GEE) revealed breast feeding can promote infant physical development and growth, and cross-sectional analysis with canonical correlation showed protein intake with breast milk as its main source brought about infants to develop physically tall and lean at first, which might support the theory that protein intake affects more on their development and growth. The extent of infant physical development and growth varied with the amount of breast milk of his or her mother, which should be caught attention in comparison of infant physical development with different feeding patterns. It is suggested that intervention of breast feeding should be implemented during perinatal period and 1-2 months after delivery with emphasis on health education.
This study investigated the influence of patient and provider gender on the outcomes of medication-history interviewing. In a previous study, 112 pharmacy students conducted medication-history interviews with 2 simulated patients. A secondary analysis was accomplished using complete data from 85 of the original 112 pharmacy students. The other 27 students were eliminated because of missing data. Factor analysis and canonical correlation were used to assess associations between the prior study's set of predictor variables and measures of interview completeness and patient satisfaction with the interview. Female and male pharmacy students appear to use different expressive, interactive, and interrogative skills. Allergy-asking was more complete when female pharmacy students interviewed a male patient. Emotive patient satisfaction was found to be associated more positively with a female student and female patient while teleological patient satisfaction between a male student and male patient was nearly double the result of the female-female dyad. Medication-history interview outcomes appear to differ as a consequence of the use of different sets of skills during same-sex or opposite-sex interviews.
It has been noticed that converged conformations of B-DNA oligomers obtained in MD calculations often have very small atom position rmsd values from the canonical B-DNA and all helical parameters close to the standard values, but their minor grooves tend to be somewhat narrower. This apparent bias disappears, however, when C5' rather than phosphorus atoms are used for measuring the groove width. At the origin of this effect is the specific orientation of phosphate groups in the canonical B-DNA model which maximizes their separation across the minor groove. When measured by C5' traces, minor groove profiles of experimental structures available in the Nucleic Acids Database show much less tendency to narrow below the canonical width. Correlation analysis reveals a high degree of correspondence in shapes of minor grooves of calculated and experimental single-crystal structures of B-DNA oligomers.