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PubMed2000

Isometric pull and push strengths of paraplegics in the workspace: 2. Statistical analysis of spatial factors.

The effect of reach levels, horizontal angles, and vertical angles on isometric pull and push strengths of male and female was determined. Highly significant increases in men's push strength were found between extreme to maximum reaches, and from extreme to normal reaches. However, for women's push strength, a significant increase was found only between extreme to maximum reach. Significant or highly significant increases were found in men's and women's pull strength between the horizontal angle (theta) sagittal through the active shoulder (90 degrees ) and other angles (0, 45, and 135 degrees ). However, for men's push strength, highly significant increases were found between the horizontal angle 45 degrees from the frontal plane, and other angles. For women's push strength, significant or highly significant increases were found between the horizontal angles 0 degrees and angles of 90 and 135 degrees. For men's and women's pull strength, significant or highly significant increases were found between the vertical angle (phi), 90 degrees, and other angles (-20, 0, and 45 degrees ). Similar increases were found for women's push strength between the 45 degrees angle and other angles. In the design of a workstation for paraplegics that requires pull and push forces, consideration must be given to the spatial factors.

Adult↗
PubMed1991

A statistical analysis of the factors that determine the age at which babies start walking.

To clarify the factors that determine the age when walking begins, this study first applied contingency tables and the chi 2 test to the questionnaire-data answered by the parents of 395 children. Among twelve factors, those that were not independent of the age of first walking were the use of a walker (p less than 0.01), the frequency of being carried on the chest (p less than 0.05) and the age of the first enrollment at a day-care center (less than 0.05). Second, this study employed the "quantification method of the second type" to clarify what factors help babies start walking early and what others do not. The subjects were divided into two groups--W0 (early-walkers) and W1 (others)--, and this grouping was used as an external criterion. The order of the factors according to the range of category scores is as follows: (1) birth weight, (2) order of birth, (3) frequency of being carried on the chest, (4) season of birth, (5) use of a walker, (6) age of the first enrollment at a day-care center. These factors included those that were not independent of the age of first walking ((3), (5), (6)). Therefore, the factors that had a wider range seem to be important in determining the age when babies start walking.

Age Factors↗
PubMed1989

Which patients with chronic hepatitis B virus infection will respond to alpha-interferon therapy? A statistical analysis of predictive factors.

Twenty-one pretreatment variables were assessed for their significance in response prediction using data from 114 patients given alpha-interferon for chronic hepatitis B virus infection. In those patients who had received a minimum of 90 million units per m2 total dose over 12 weeks, a negative anti-human immunodeficiency virus antibody status (p less than 0.001), chronic active hepatitis on liver biopsy (p less than 0.005), high AST level (p less than 0.001), low hepatitis B virus DNA level (p less than 0.001) and a history of acute hepatitis (p less than 0.005) were all associated with an increased likelihood of response on univariate analysis. On stepwise logistic regression analysis, hepatitis B virus DNA, AST and a history of acute hepatitis predicted response independently (p less than 0.05). The most reliable combination of predictive factors was a negative anti-human immunodeficiency virus antibody status, with either a positive history of acute icteric hepatitis and AST greater than 45 IU per liter or no history of acute icteric hepatitis and AST greater than 85 IU per liter, which predicted response in 77% with a specificity of 79% (p less than 0.001). The loss of HBsAg in addition to HBeAg and hepatitis B virus DNA was more likely to occur in patients with chronic infection of less than 2 years duration (p less than 0.001).

Adult↗
PubMed2003

Validation of measures of middle schoolers' self-efficacy for physical and emotional health, and academic tasks.

The development and psychometric study of a measure of middle schoolers' perceptions of self-efficacy for physical, emotional, and academic behaviors appropriate to their age and developmental tasks are described. The validation of the Middle School Self-Efficacy Questionnaire (MISSE) included the adaptation of existing items and the generation of new ones. Items were subjected to judges' review by two expert panels and were tested with a large, geographically diverse sample of youngsters aged 11-14. Statistical analyses included factor analysis, internal consistency estimations, t tests, and analyses of variance for hypothesis testing related to construct validity. Results showed support for the expected factors and provided evidence of the validity of the MISSE.

Adolescent↗
PubMed2003

Metabolic syndrome best defines the multivariate distribution of blood variables in postinfarction patients.

The hypothesis was tested that metabolic syndrome (MS) plays a leading role in approximating the multivariate distribution of thrombogenic and metabolic blood variables in a population of postinfarction patients. The multivariate statistical technique of factor analysis was used to determine blood variable clustering 2 months after myocardial infarction. Five clusters resulted in two separate independent factors, dyslipidemia and metabolic, reflecting MS and the remaining interpreted as cholesterol-lipoprotein, vascular-inflammatory, and coagulation. All five factors accounted for 55% of total variance with MS-associated factors accounting for 20% and individual factor contributions as follows: 11.6, 8.6, 12.9, 11.9, and 9.6%, respectively. There were no interactions of metabolic variables with thrombogenic variables or CRP in any factor. Results of subgroup analysis in males and females and in patients on and not on statins were all similar to the total group. We conclude there is no interaction of variables of MS or cholesterol-lipoprotein factors with those of thrombogenic factors. This independence yields the potential for use of factors in evaluating CVD risk. Further, the importance of MS in this group of postinfarction patients is emphasized, as the largest contribution to total variance was from MS factors, meaning that these variables best approximate the original multivariate distribution.

Aged↗
PubMed2006

The SF-36 physical and mental health factors were confirmed in cancer and HIV/AIDS patients.

BACKGROUND AND OBJECTIVE: This study assesses the extent to which the RAND-36/SF-36 items measure physical and mental health (PH and MH), as implied by existing summary scoring systems. METHODS: A total of 1,714 heterogeneous cancer and HIV/AIDS patients were recruited from five institutions. Of these, 56% were women; 81% Caucasians; and about 10% were from each of the major cancer types and HIV/AIDS. RESULTS: Analyses of the SF-36 confirmed the two dimensions of health namely physical and mental. However, item fit statistics and residual factor analysis revealed that some items intended to represent the PH dimension fit better with the MH dimension. CONCLUSION: This paper demonstrated the value of Rasch residual factor analysis for understanding and enhancing interpretation of health.

Activities of Daily Living↗
PubMed2006

Impact of pediatric epilepsy on Indian families: influence of psychopathology and seizure related variables.

The impact of epilepsy on families has been little studied in the developing countries, where it is the most common neurological disorder among children. In Vellore, India, the impact on 132 families who had a child with epilepsy was rated with the Impact of Pediatric Epilepsy on the Family Scale (IPES). An adverse impact was experienced by 42% of families. Multivariate statistical analysis revealed four factors that were significantly associated with high impact: fewer years since diagnosis (OR=0.81, 95% CI=0.71-0.93), fewer months since last seizure (OR=0.58, 95% CI=0.39-0.87), treatment with multiple antiepileptic drugs (OR=4.34, 95% CI=1.22-15.52), and increased behavior problem scores on the Child Behavior Checklist (OR=1.10, 95% CI=1.05-1.14). Factor analysis of the IPES was also conducted as a comparison with earlier findings in a developed country. We suggest that early monotherapy should be employed whenever possible and that early recognition and treatment of associated psychological problems may help to reduce the burden on families.

Adaptation, Psychological↗
PubMed1996

The emotional experience of hospitalization: its moderators and its role in patient satisfaction with foodservices.

OBJECTIVES: To investigate the basic dimensions of patient emotional experience of hospitalization; to identify the moderators of emotional experience in terms of individual characteristics and contextual factors; and to investigate the contribution of the dimensions of the patient emotional experience to satisfaction with foodservices. DESIGN: Survey questionnaire. SUBJECTS/SETTING: One hundred two hospitalized patients of a specialized, acute-care, urban hospital in Canada who required one or more overnight stays. Patients with notable physical, cognitive, or emotional limitations were excluded from the study. Patients admitted to the obstetrics department were also excluded because of the unique nature of their emotional experience of hospitalization. STATISTICAL ANALYSES PERFORMED: Factor analysis followed by orthogonal rotation (varimax), analyses of variance, and multiple regression analyses. RESULTS: Five dimensions represented the emotional experience of hospitalization: positive emotions, arousal emotions, and three negative dimensions structured on the basis of their possible causes (situation-, other-, or self-attributed negative emotions). Individual characteristics (gender, age, marital status, perceived health status) and contextual factors (perceived control over the situation, complexity of medical diagnosis, and admission procedures) significantly influenced patient emotions. Satisfaction with foodservices was structured in technical and interpersonal dimensions; the largest part of the common variance was accounted for by interpersonal aspects. The relationship between emotions and satisfaction was direct for positive emotions and, surprisingly, for situation-attributed negative emotions and self-attributed negative emotions. Other-attributed negative emotions and arousal emotions were negatively associated with satisfaction with foodservices. APPLICATIONS: Results suggest that dietitians' interventions should be adapted for subgroups of patients who experience different emotions. Results also provide insights on individual and contextual factors that can be used to identify or better understand the specific characteristics of these subgroups. The pattern of relationships between emotions and satisfaction demonstrates that the fine-tuning of dietitians' interventions as a function of patients' emotional states may be conducive to increased patient satisfaction with foodservices.

Adult↗
PubMedDate not supplied

Perceptions of community nutrition and health needs in the Lower Mississippi Delta: a key informant approach.

OBJECTIVE: Key informants' perceptions of nutrition and health needs in their southern rural communities were assessed prior to nutrition intervention planning. DESIGN: This cross-sectional survey used in-person interviews. SUBJECTS/SETTINGS: A sample of 490 individuals from 12 professional and lay roles in 8 community sectors in 36 counties in Arkansas, Louisiana, and Mississippi was chosen. STATISTICAL ANALYSES PERFORMED: Factor analysis was carried out on reported food, nutrition, and health problems and contributing factors. The General Linear Models procedure identified within- and between-subject effects for factors. Tukey's post hoc tests identified differences between sectors and states. Frequencies and weighted rankings were computed for health problems. RESULTS: Key informants rated individual-level factors (food choices, education, willingness to change, health behavior) as more important than community-level factors (food and health care access, resources) with regard to nutrition and health problems and contributors to problems. The number one health problem was hypertension. IMPLICATIONS: Key informants are knowledgeable about nutrition and health problems, contributing factors, and available resources. Individual factors were perceived as more important contributors to nutrition and health problems providing valuable information for planning nutrition interventions.

Adolescent↗
PubMed1979

Multivariate analysis and quantitative structure-activity relationships. Inhibition of dihydrofolate reductase and thymidylate synthetase by quinazolines.

Quantitative structure-activity relationships (QSAR) have been established for the inhibition of dihydrofolate reductase and thymidylate synthetase by 2,4-diaminoquinazoline-glutamic acid analogues. For dihydrofolate reductase from both human acute lymphocytic leukemia cells and murine L1210R cells, QSAR's obtained with 50 quinazolines were similar. On the other hand, for the inhibition of thymidylate synthetase from murine L1210S cells and from Lactobacillus casei, QSAR's formulated on the basis of data measured with 33 compounds were different, indicating that the two enzymes are dissimilar. The use of multivariate statistics including cluster analysis, factor analysis, and discriminant analysis is shown to facilitate the formulation of a satisfactory correlation equation. The procedure is demonstrated by the development of QSAR for the inhibition of thymidylate synthetase.

Analysis of Variance↗
PubMedDate not supplied

Statistical analysis of some factors affecting the number of horse births in France.

Declarations of matings (535,746) and 308,549 consecutive declarations of birth from 1989 to 1999 were analysed by logistic regression in order to determine the effects of year, breed and age of parents on numerical productivity (the number of foals declared per mated mare per year). For the years 1994 to 1999, the status of the mare, type of mating and month of first mating, were also available. The effect of inbreeding and, for warm-blooded horses, the effect of the level of performances or the effect of the level of breeding value estimation were also analysed. The main results are the following: numerical productivity progressed in France more for draught breeds than for saddle breeds and trotters. Thoroughbreds progressed less and just reached the level of significance. Cold-blooded horses, however, appeared less productive than warm-blooded horses for which thoroughbreds were at the lower level. It cannot be concluded if this figure reveals biological differences in fertility or if it is only the result of differences in managing the official declarations. For warm-blooded horses, the absence of negative relationships between the trends of selection and numerical productivity results appeared clearly. A high performance level for the mare was positively associated with higher productivity results in sport and trotting horses and showed no significant influence for galloping horses. The relationships with breeding value estimation illustrated the same trends.

Age Factors↗
PubMed2004

How reliable are assessments of clinical teaching? A review of the published instruments.

BACKGROUND: Learner feedback is the primary method for evaluating clinical faculty, despite few existing standards for measuring learner assessments. OBJECTIVE: To review the published literature on instruments for evaluating clinical teachers and to summarize themes that will aid in developing universally appealing tools. DESIGN: Searching 5 electronic databases revealed over 330 articles. Excluded were reviews, editorials, and qualitative studies. Twenty-one articles describing instruments designed for evaluating clinical faculty by learners were found. Three investigators studied these papers and tabulated characteristics of the learning environments and validation methods. Salient themes among the evaluation studies were determined. MAIN RESULTS: Many studies combined evaluations from both outpatient and inpatient settings and some authors combined evaluations from different learner levels. Wide ranges in numbers of teachers, evaluators, evaluations, and scale items were observed. The most frequently encountered statistical methods were factor analysis and determining internal consistency reliability with Cronbach's alpha. Less common methods were the use of test-retest reliability, interrater reliability, and convergent validity between validated instruments. Fourteen domains of teaching were identified and the most frequently studied domains were interpersonal and clinical-teaching skills. CONCLUSIONS: Characteristics of teacher evaluations vary between educational settings and between different learner levels, indicating that future studies should utilize more narrowly defined study populations. A variety of validation methods including temporal stability, interrater reliability, and convergent validity should be considered. Finally, existing data support the validation of instruments comprised solely of interpersonal and clinical-teaching domains.

Academic Medical Centers↗
PubMed1993

Assessment of the patient with acute asthma in the emergency department. A factor analytic study.

Acute asthma is a very common medical emergency. Thus, a variety of measures are currently used to assess severity; most are logical and seem reasonably effective but have never been scientifically tested in a comprehensive manner. Additionally, simple brief measures are needed for greater specificity in describing variables and in assessing different aspects of asthma. The purpose of this study was to examine the most common clinical and objective measures utilized in the assessment of acute asthma in the emergency department for determining whether these variables comprise separate or distinct dimensions. To carry out the above purpose, we used the multivariate statistical technique of factor analysis. Measures of age, duration of attack, heart rate, respiratory rate, peak expiratory flow (PEF), FVC, FEV1 percent of predicted, accessory-muscle use, dyspnea, wheezing, steroid use, and early response to treatment in 194 patients with acute asthma (mean age = 32.8 +/- 11.9 years) were factor analyzed through the method of principal components. Factors extracted with this method were then rotated orthogonally through the Varimax procedure. The first factor contained the three measures of lung function (PEF, FVC, and FEV1 percent of predicted) and early response of treatment. The second factor extracted contained respiratory rate, accessory-muscle use, and dyspnea. Factor 3 contained heart rate and wheezing, and factor 4 contained age, duration of attack, and steroid use. Exploratory analysis of subgroups (by randomization, by severity of airflow obstruction, and by use of steroids) confirmed the results of the primary analysis. The coefficients of congruence obtained were above 0.90. Early response of treatment measured by the percent variation of FEV1 at 30 min over baseline value significantly correlated with a broad variety of asthma characteristics (PEF, FVC, FEV1 percent of predicted, accessory-muscle use, and duration of attack), resulting in a rather general measure, and suggesting that its measure can be a reliable assessment of acute adult asthma. Finally, early response to treatment was the most important predictor of the patient outcome (r = 0.48, p < 0.00). In summary, the results of this study support the hypothesis that most of the subjective and objective measures utilized in the assessment of patients with acute adult asthma represent separate and nonoverlapping dimensions and provided a useful summary of acute asthma. Early response to treatment in combination with measures of the four identified factors could be included in other acute adult asthma research protocols promoting greater comparable among studies.

Acute Disease↗
PubMedDate not supplied

The adolescent role assessment: psychometric properties and theoretical usefulness.

OBJECTIVE: Fostering career adaptability may improve vocational outcomes for adolescents. This study examined the responses of adolescents on the Adolescent Role Assessment (ARA) to explore its usefulness as a measure of career adaptability. METHOD: The ARA was administered to 101 adolescents 12 to 17 years of age. Descriptive statistics, reliability analysis, and factor analysis were generated from the ARA scores. Dominant narrative themes were coded into the six domains of the ARA and into the domains identified in the factor analysis. RESULTS: The internal consistency of the ARA was low with few differences in findings across age. The identified factors--developing aspirations, self-efficacy, interpersonal competencies, and autonomy--are consistent with constructs of career adaptability found in the literature and differentiated low and high scorers. CONCLUSION: Major changes to the ARA content and scaling or development of a new assessment of career adaptability using the factor structure are recommended for clinical and research applications.

Adolescent↗
PubMed1993

[Statistical analysis of recurrent factors in superficial bladder cancer. Natural history of superficial bladder cancer].

Three hundred thirty-six patients with superficial bladder cancers underwent their initial surgery at the Department of Urology of Okayama University School of Medicine from 1961 to 1985. They have been followed-up until December 1988 (the median: 68 months). Among the 336 cases, excluding 9 cases which were treated initially with total cystectomy or incomplete resection, the remaining 327 cases were reviewed in order to study the pattern of their local recurrences in the bladder. Major factors affecting recurrences of superficial bladder cancer were evaluated by the multivariate analysis using Cox's proportional hazard model. The examined factors included age on admission, sex, tumor's number, size, stage, histological grade and shape, operative method, intravesical chemotherapy, systemic chemotherapy, radiotherapy, frequency of recurrences and the date of operation. During the follow-up period, 179 cases out of the 327 cases did not show any recurrences. The remaining 148 cases recurred from once to 11 times, therefore, a total number of recurrences was counted to be 406. In the 406 recurrences, 338 recurrences were treated by TUR, SVR, or SR. The remaining 68 recurrences were treated with total cystectomy or untreated. Fifty-seven cases out of the 148 cases demonstrated recurrences more than 3 times. Only 4 cases were free from recurrences more than 24 months following the surgery for their last recurrences. The analysis in the 327 primary cases showed that the number of tumors was the most important factor. On the other hand the analysis in 338 recurrences showed that the second most important factor was the frequency of recurrences, following the number of tumors.(ABSTRACT TRUNCATED AT 250 WORDS)

Carcinoma, Transitional Cell↗