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Pairwise Correlations (pairwise + correlation)
Selected AbstractsParents and Practitioners Are Poor Judges of Young Children's Pain SeverityACADEMIC EMERGENCY MEDICINE, Issue 6 2002Adam J. Singer MD Objective: Visual analog pain scales are reliable measures in older children and adults; however, pain studies that include young children often rely on parental or practitioner assessments for measuring pain severity. The authors correlated patient, parental, and practitioner pain assessments for young children with acute pain. Methods: This was a prospective, descriptive study of a convenience sample of 63 emergency department patients aged 4-7 years, with acute pain resulting from acute illness or painful invasive procedures. A trained research assistant administered a structured pain survey containing demographic and historical features to all parents/guardians. Children assessed their pain severity using a validated ordinal scale that uses five different faces with varying degrees of frowning (severe pain) or smiling (no pain). Each face was converted to a numeric value from 0 (no pain) to 4 (severe pain). Parents and practitioners independently assessed their child's pain using a validated 100-mm visual analog scale (VAS) marked "most pain" at the high end. Pairwise correlations between child, parent, and practitioner pain assessments were performed using Spearman's or Pearson's test as appropriate. The association between categorical data was assessed using ,2 tests. Results: Sixty-three children ranging in age from 4 to 7 were included. Mean age (±SD) was 5.7 (±1.1); 42% were female. Fifty-seven successfully completed the face scale. The distribution of the children's scores was 0-17%, 1-9%, 2-30%, 3-14%, and 4-30%. Mean parental and practitioner scores (±SD) on the VAS were 61 (±26) mm and 37 (±26) mm, respectively (maximal = 100 mm). Correlation between child and parent scores was 0.47 (p < 0.001). Correlation between child and practitioner scores was 0.08 (p = 0.54). Correlation between parent and practitioner scores was 0.04 (p = 0.001). Conclusions: There is poor agreement between pain ratings by children, parents, and practitioners. It is unclear which assessment best approximates the true degree of pain the child is experiencing. [source] Predictors of medication compliance among older heart failure patientsINTERNATIONAL JOURNAL OF OLDER PEOPLE NURSING, Issue 4 2007Krystyna Cholowski PhD Aim. To examine relationships between psycho-social and patho-physiological measures in explaining medication compliance in older heart failure (HF) patients. Background. Self-efficacy is a predictor not only of medication compliance, but also health recovery. How older HF patients conceptualize and manage this life-threatening event is central to ongoing rehabilitation. Regulating ongoing medical and lifestyle changes in the rehabilitation process requires that any underlying negative affect be productively managed by the use of appropriate coping strategies. Method. Using an exploratory correlational design, 51 older HF patients were asked to complete the Beck Depression Inventory, Beliefs about Medication and Diet Questionnaire, Reactions to Daily Events Questionnaire and Self-regulation scale. A self-report measure of medication compliance was obtained as part of a semi-structured interview. The study was conducted in 2003,2004. Results. Using descriptive statistics, patho-physiological and psychosocial characteristics were given. Independent t -tests were used to assess the gender effects. Pairwise correlations were used to examine the relationships between presenting circumstances, psychosocial characteristics, medication compliance beliefs and self-reported medication compliance behaviours. All positive coping strategies and self-regulation were associated with positive intentions in medication compliance. Males were more inclined towards proactive coping and self-regulatory strategies than were females. Increased depressive symptoms were linked to carelessness in compliance. A belief in medication compliance was associated with a reduced likelihood of carelessness Conclusion. Bandura's three conditions for agency in rehabilitation, self-efficacy and goal-directed intention appeared to be important even in the early phase of the programme. Positive coping strategies and self-regulation suggests a positive basis for medication compliance and more successful ongoing rehabilitation for older HF patients. We identify a significantly enhanced educative role for nurses in this context. Relevance to clinical practice. We suggest that nurses dealing with compliance issues among older patients need to monitor behaviour through addressing both the quality of affect during the patient's response to HF (self-concept, -esteem and -efficacy) as well as the quality of health-related metacognitive knowledge underlying the self-regulatory decisions (such as the patients conceptions of ,wellness' and the strategic knowledge underpinning its achievement and maintenance). [source] Resource specialization in a phytophagous insect: no evidence for genetically based performance trade-offs across hosts in the field or laboratoryJOURNAL OF EVOLUTIONARY BIOLOGY, Issue 4 2009S. J. AGOSTA Abstract We present a field test of the genetically based performance trade-off hypothesis for resource specialization in a population of the moth Rothschildia lebeau whose larvae primarily feed on three host plant species. Pairwise correlations between growth vs. growth, survival vs. survival and growth vs. survival across the different hosts were calculated, using families (sibships) as the units of analysis. Of 15 pairwise correlations, 14 were positive, 5 significantly so and none were negative. The same pattern was found using complementary growth and survival data from the laboratory. Overall, we found no evidence of negative genetic correlations in cross-host performance that would be indicative of performance trade-offs in this population. Rather, variation among families in performance appears to reflect ,general vigour' whereby families that perform well on one host perform well across multiple hosts. We discuss the implications of positive genetic correlations in cross-host performance in terms of the ecology and evolution of host range. We argue that this genetic architecture facilitates colonization of novel hosts and recolonization of historical hosts, therefore contributing to host shifts, host range expansions, biological invasions and introductions, and host ranges that are regionally broad but locally narrow. [source] An Adaptive Hierarchical Test Procedure for Selecting Safe and Efficient TreatmentsBIOMETRICAL JOURNAL, Issue 4 2006Franz König Abstract We consider the situation where during a multiple treatment (dose) control comparison high doses are truncated because of lack of safety and low doses are truncated because of lack of efficacy, e.g., by decisions of a data safety monitoring committee in multiple interim looks. We investigate the properties of a hierarchical test procedure for the efficacy outcome in the set of doses carried on until the end of the trial, starting with the highest selected dose group to be compared with the placebo at the full level ,. Left truncation, i.e., dropping doses in a sequence starting with the lowest dose, does not inflate the type I error rate. It is shown that right truncation does not inflate the type I error if efficacy and toxicity are positively related and dose selection is based on monotone functions of the safety data. A positive relation is given e.g. in the case where the efficacy and toxicity data are normally distributed with a positive pairwise correlation. A positive relation also applies if the probability for an adverse event is increasing with a normally distributed efficacy outcome. The properties of such truncation procedures are investigated by simulations. There is a conflict between achieving a small number of unsafely treated patients and a high power to detect safe and efficient doses. We also investigated a procedure to increase power where a reallocation of the sample size to the truncated treatments and the control remaining at the following stages is performed. (© 2006 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] The surface winds of Sweden during 1999,2000INTERNATIONAL JOURNAL OF CLIMATOLOGY, Issue 2 2006Christine Achberger Abstract This study aims at increasing our understanding of the regional wind climate in Sweden. Spatial and temporal patterns of the surface winds are presented for the years 1999,2000. Annual mean wind speeds range between 2 and 5 m/s with high values at exposed mountainous sites and on islands off the coast. Combining wind speed and direction into mean wind velocities shows that flow conditions are stronger and more coherent in space in southern Sweden than in central and northern Sweden. The spatial scale, defined as the distance between stations when the correlation for wind speed drops to ,0.37, was determined by pairwise correlations between all possible station pairs. Scales range from 38 to 530 km for wind speed and from 40 to 830 km for wind direction depending on the region. They tend to be smaller in central and northern Sweden, where the more pronounced relief has a larger influence on the local wind conditions. The strength and the timing of the annual and diurnal wind speed cycle have been estimated for each station. Amplitudes of the annual cycle are greater at exposed sites and correlate generally well with annual mean wind speeds. Monthly mean wind speeds peak in winter in southern Sweden, but peak in other seasons in the remaining regions. In winter, weaker pressure gradients over northern Sweden and surface-near temperature inversions contribute to weaker surface winds. Diurnal cycles vary in strength between summer and winter. Compared to the last normal climate period (1961,1990), 1999,2000 is characterized by the increased occurrence of westerly and southerly geostrophic flow. Copyright © 2005 Royal Meteorological Society. [source] Resource specialization in a phytophagous insect: no evidence for genetically based performance trade-offs across hosts in the field or laboratoryJOURNAL OF EVOLUTIONARY BIOLOGY, Issue 4 2009S. J. AGOSTA Abstract We present a field test of the genetically based performance trade-off hypothesis for resource specialization in a population of the moth Rothschildia lebeau whose larvae primarily feed on three host plant species. Pairwise correlations between growth vs. growth, survival vs. survival and growth vs. survival across the different hosts were calculated, using families (sibships) as the units of analysis. Of 15 pairwise correlations, 14 were positive, 5 significantly so and none were negative. The same pattern was found using complementary growth and survival data from the laboratory. Overall, we found no evidence of negative genetic correlations in cross-host performance that would be indicative of performance trade-offs in this population. Rather, variation among families in performance appears to reflect ,general vigour' whereby families that perform well on one host perform well across multiple hosts. We discuss the implications of positive genetic correlations in cross-host performance in terms of the ecology and evolution of host range. We argue that this genetic architecture facilitates colonization of novel hosts and recolonization of historical hosts, therefore contributing to host shifts, host range expansions, biological invasions and introductions, and host ranges that are regionally broad but locally narrow. [source] Estimating a Multivariate Familial Correlation Using Joint Models for Canonical Correlations: Application to Memory Score Analysis from Familial Hispanic Alzheimer's Disease StudyBIOMETRICS, Issue 2 2009Hye-Seung Lee Summary Analysis of multiple traits can provide additional information beyond analysis of a single trait, allowing better understanding of the underlying genetic mechanism of a common disease. To accommodate multiple traits in familial correlation analysis adjusting for confounders, we develop a regression model for canonical correlation parameters and propose joint modeling along with mean and scale parameters. The proposed method is more powerful than the regression method modeling pairwise correlations because it captures familial aggregation manifested in multiple traits through maximum canonical correlation. [source] | |||||||||||||