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At least 19 recordsLinked to original sources
PubMed1984

Statistical factor analysis and cluster analysis in the etiology of climacteric symptoms.

Factor analysis and cluster analysis were applied to a set of 17 climacteric symptoms data obtained from 194 premenopausal and postmenopausal women. Six distinct factors were extracted and the women were divided into 7 groups by hierarchical cluster analysis in terms of their factor scores. Only one representative factor was identified in 3 groups out of the 7. These 3 groups including 87 women were tentatively designated as vasomotor symptom, neurotic, and sensory disturbance groups. These results confirmed statistically that at least 3 simple etiological factors exist among climacteric symptoms.

Adult↗
PubMed2005

Statistical factor analysis of aerial spectrometric data, Al-Awabed area, Syria: a useful guide for phosphate and uranium exploration.

Factor analysis provides a quantitative interpretation for synthesizing and correlating data from airborne spectrometric surveys. Factor analysis is applied on such data of Al-Awabed area, Northern Palmyrides. The seven variables used in this research are: total radioactivity Ur1, e(U), e(Th), K%, e(U)/e(Th), e(U)/K and e(Th)/K. The analysis and interpretation show that a model of four factors (F1, F2, F3 and F4) is sufficient to represent them, where 94% of total data variance is interpreted. Mapping of these four factors proved to be a powerful tool for a direct differentiation of various rocks units, and a score lithological map of 11 radiometric units was established.

Journal Article↗
PubMed2006

Identifying spectrometric signatures of phosphate deposits and enclosing sediments in Al-Awabed area, Northern Palmyrides, Central Syria, by the use of statistical factor analysis.

In previous published research, a factor analysis approach has been applied to airborne spectrometric data of Al-Awabed area, Northern Palmyrides, Syria. A model of four factors (F1, F2, F3 and F4) has proven to be sufficient to represent the acquired data, where 94% of the total data variance is explained. A powerful tool for direct differentiation of various rocks units is obtained through the mapping of these four factors, where a scored lithological map including 11 radiometric units is established. Ninety nine rock samples have been taken according to the four factors to be analyzed by the gamma-spectrometry technique in order to determine their content of eU, eTh and K%. The analysis of 65 samples according to F1 indicates that uranium concentration varies between 2.74 and 123.3 ppm with an average of 58.85 ppm and a standard deviation of 32.53 ppm. The analysis of 18 samples taken according to F2 indicates that K% concentration varies between 0.001 and 0.324 with an average of 0.145 and a standard deviation of 0.122. The analysis of 16 samples taken according to F3 indicates that K% concentration varies between 0.024 and 0.558 with an average of 0.227 and a standard deviation of 0.133. These gamma-results are expected and fit very well with the results obtained by the factor analysis approach. Therefore, the validity and efficacy of the factor analysis approach, to be widely used as a guide in exploration and smart sampling for mining programs, are well demonstrated. The established phosphate maps show a width extension and distribution, and clearly indicate the potential of the research area, and it merits to be followed by economic exploration.

Journal Article↗
PubMed2005

The influence of academic projects on the professional socialization of family medicine faculty.

BACKGROUND: Successful academic physicians acquire and maintain productive colleague relationships, understand unwritten rules of academe, and effectively manage their careers. Developing these professional socialization skills are goals of some faculty development programs (FDPs), but there is scant evidence about whether such programs are effective. METHODS: A nationwide retrospective, cross-sectional written survey was conducted in two phases: (1) FDP directors who received US Department of Health and Human Services, Health Resources and Services Administration support between 1994 and 1997 described program activities and provided enrollee rosters and (2) enrollees reported socialization and colleague outcomes. Instruments were developed, pilot tested, and administered for this study. Analysis utilized descriptive statistics, factor analysis, and ANOVA. RESULTS: Of 52 eligible directors, 37 (71%) provided FDP activity details and rosters. Of 543 eligible enrollees, 351 (65%) returned surveys. A key result of factor analysis was a seven-item scale related to academic project activities. FDPs with greater emphasis on these activities were associated with enrollees reporting higher levels of colleague relationships and professional socialization skills. CONCLUSION: This study's factor analysis indicates that certain FDP project activities are positively associated with enrollees' professional socialization outcomes.

Adult↗
PubMed1994

A statistical analysis of factors related to symptomatic cerebral vasospasm.

A retrospective review of patients presenting to our institution with aneurysmal subarachnoid hemorrhage between 1980-1990 was accomplished. Eleven variables were examined as to their relationship to clinical vasospasm: age, sex, clinical grade, amount of subarachnoid blood on CT, aneurysm location, incidence of vasospasm, incidence of complications, use of calcium channel blockers, time to surgery, length of stay, and outcome. Data were analyzed with univariate and multivariate logistical regression methodology. By univariate analysis, age under 20, amount of subarachnoid hemorrhage, and clinical grade were associated with a higher risk of vasospasm. Using multivariate logistic regression, these factors, along with age under 35, were correlated as being predictive of clinical vasospasm. When all patients are grouped into either good or bad outcome, and a similar analysis is performed, only in the poor outcome group is the amount of subarachnoid hemorrhage and clinical grade correlated with vasospasm. This suggests that there is a group of patients with a predisposition to vasospasm that is independent of subarachnoid hemorrhage and clinical grade, and that these patients may have a more favorable outcome.

Adolescent↗
PubMedDate not supplied

Ambulation in patients with myelomeningocele: a multivariate statistical analysis.

Factors determining ambulation in 163 patients with myelomeningocele were studied by a multivariate statistical method. Neurological dysfunction unrelated to the plaque was analyzed by magnetic resonance imaging. There were no ambulators at the thoracic or L1-L2 level. At the L3 level, 54% ambulated, and at the L4 level, 67% ambulated. Eighty percent were ambulators at L5 and all at the sacral level. Below L1-L2, one-half of the nonambulators had neurological deficiencies caused by syringohydromyelia or Chiari malformations preventing ambulation. Severe scoliosis was closely, age moderately, and hip flexion contracture slightly related to the inability of the other nonambulators to walk, while pelvic obliquity, hip dislocation, or knee flexion contracture was not.

Adolescent↗
PubMed2004

The Quality of Life Impact of Refractive Correction (QIRC) Questionnaire: development and validation.

BACKGROUND: The purpose of the study was to develop a questionnaire that could quantify the quality of life (QOL) of people with refractive correction by spectacles, contact lenses, and refractive surgery in the prepresbyopic age group. METHODS: The questionnaire was developed and validated using traditional methods and Rasch analysis. A 90-item pilot questionnaire was developed through extensive literature search and use of professional and lay focus groups. Pilot study data were obtained from 306 subjects for item reduction to produce the 20-item Quality of Life Impact of Refractive Correction (QIRC) questionnaire. Validity and reliability studies (test-retest reliability with intraclass correlation coefficient and Bland-Altman limits of agreement, and internal consistency with Rasch fit statistics, factor analysis, and Cronbach's alpha) were performed from data of an additional 312 subjects. RESULTS: Rasch analysis demonstrated QIRC has good precision, reliability, and internal consistency (person separation, 2.03; reliability, 0.80; root-mean-square measurement error, 3.25; mean square +/- SD infit, 0.99 +/- 0.38; outfit, 1.00 +/- 0.39; item infit range, 0.70 to 1.24; and item outfit range, 0.78 to 1.32). The items (mean score, 50.3 +/- 7.3) were well targeted to the subjects (mean score, 47.8 +/- 5.5) with a mean difference of 2.45 (scale range, 0 to 100) units. Test-retest reliability (intraclass correlation coefficient, 0.88; coefficient of repeatability, +/-6.85 units), factor loading range (0.40 to 0.76), and Cronbach's alpha (0.78) also indicated the reliability and validity of QIRC. CONCLUSIONS: The 20-item QIRC questionnaire, which quantifies the QOL of people with refractive correction by spectacles, contact lenses, and refractive surgery in the prepresbyopic age group, was developed using Rasch analysis and shown to be valid and reliable. The use of Rasch scaling allows scores to be treated as a valid continuous variable. QIRC has broad applicability for cross-sectional and outcomes research.

Adult↗
PubMed1994

Quality of patient meal service in hospitals: delivery of meals by dietary employees vs delivery by nursing employees.

OBJECTIVE: To compare patient assessment of meal-service quality and employee-service orientation in hospitals where dietary employees deliver meals trays and in hospitals where nursing employees deliver meal trays. DESIGN: Survey. SETTING: General, medical-surgical (not Veterans Administration) hospitals of 300 to 500 beds with a self-operated foodservice department and a centralized, conventional food production system. SUBJECTS: 552 patients and 192 employees in nine hospitals geographically dispersed in the midwestern and eastern United States. Dietary employees delivered meal trays in five of the hospitals and nursing employees delivered trays in four. MAIN OUTCOME MEASURES: On a five-point scale, patients indicated level of agreement with 16 statements about hospital meal service. Employees who delivered meal trays rated their agreement with 20 service orientation statements on a five-point scale. STATISTICAL ANALYSIS: Factor analysis with varimax rotation, chi 2 analysis, and analysis of variance. RESULTS: Patient assessment of the quality of meal service was multidimensional. Patients gave more positive ratings to characteristics of the personnel delivering the tray than to the quality of the food. Patients in hospitals were dietary employees delivered meal trays rated the quality of food significantly higher (P < .01) than did patients in hospitals where nursing employees delivered trays. Service orientation of the personnel delivering the trays was also multidimensional. Dietary and nursing employees did not differ in their personal motivation toward providing service; however, dietary employees rated the organizational support for providing service significantly higher (P < .001) than did nursing employees. Nursing employees were significantly more positive (P < .05) than dietary employees about their interactions with patients. CONCLUSIONS: Patient perceptions of service quality differed in hospitals where dietary employees delivered meal trays and in those where nursing personnel delivered trays. Dietary and nursing employees differed in some aspects of their service orientation.

Adult↗
PubMed2004

Development and testing of a new instrument for measuring concerns about dying in health care providers.

A new measure of concerns about dying was investigated in this psychometric study. The Concerns About Dying instrument (CAD) was administered to medical students, nursing students, hospice nurses, and life sciences graduate students (N = 207) on two occasions; on one occasion they also completed three related measures. Analyses included descriptive statistics, factor analysis, Cronbach's alpha, test-retest correlations, t tests, and correlations with other measures. Results suggest the CAD measures three distinct but related areas: general concern about death, spirituality, and patient-related concern about death. Reliability estimates were good, and correlations with related measures were strong. Between-group differences suggest scores are related to actual differences in level of concern and beliefs about death and dying. The CAD has the advantage of being very brief and of explicitly assessing concerns about working with patients who are dying.

Adult↗
PubMed2002

Clinical parameters for assessment of udder health in Danish dairy herds.

This study examined the possibilities of using clinical parameters related to the bovine udder for characterisation of udder health. Five clinicians performed systematic clinical recordings of udder health at 3 visits to 4 dairy herds. Several of the clinical parameters were scored on an ordinal scale. The agreement between clinicians was compared using kappa statistics. Factor analysis was used to identify udder types. The clinical evaluations showed substantial variation among clinicians. Parameters that were not directly related to pathological conditions showed the highest variation e.g. length of the claws, teat shape and hardness of the udder parenchyma. On the other hand, evaluation of pathological parameters such as nodes in the udder, skin lesions and oedema showed good agreement between clinicians. Udder types identified by means of factor analysis were found to be suitable for characterisation of udder health. Especially one factor related to dry quarters and udder asymmetry showed a more consistent relationship to milk yield than traditionally applied udder health parameters such as treatment rate and cell count. It is concluded that there is a considerable need for increased efforts among clinicians in order to standardise clinical recordings. It is further concluded that certain combinations of extended clinical recordings have significant perspectives for future characterisation of udder health.

Animals↗
PubMedDate not supplied

[Attempts to divide the high-frequency range (40-200 cycle/sec) of the brain electrical activity in dogs into frequency bands].

The work was aimed to reveal the functional significance of separate narrow-frequency bands in the high-frequency range (40-200 Hz) of brain electrical activity of dogs in the process of lever-pressing instrumental conditioning. In order to divide this range into separate bands we applied one of the methods of multivariate statistics, factor analysis (FA) with varimax rotation. Values of function of spectral density in the wide range (1-200 Hz) were factorized. The structure of factors reflected both regional cortical characteristics of electrical activity and individual features. Conditioning induced changes in factor description of brain electrical activity mainly in the high-frequency part of the spectra. A number of new factors appeared which divided high-frequency band of the brain activity into narrower parts with definite functional significance.

Animals↗
PubMed1977

Statistical analysis of factors affecting survival after glioblastoma multiforme.

Statistical evaluation of 71 cases (adults) of histologically confirmed supratentorial surgically treated glioblastoma multiforme seen during the period 1958 to 1973 revealed that the state of calcification as determined by roentgenography and the histological appearance of the neoplasm appeared to have a relationship with the postoperative period of survival. Postoperative adjuvant treatment, location of the neoplasm, duration of preoperative symptoms, patient's age at onset, preoperative condition, and cystic formation in the neoplasm also appeared to have a relationship, although it was slight.

Adult↗
PubMed1982

Abdominal aortic aneurysm rupture: statistical analysis of factors affecting outcome of surgical treatment.

One hundred sixteen patients underwent surgery for ruptured abdominal aortic aneurysms with intraoperative and overall mortality rates of 20.7% and 51.7%, respectively. The correlation of multiple factors to morbidity and mortality was assessed with detailed statistical analysis. Eight preoperative factors were identified as predictors of mortality. Increased intraoperative mortality rates were associated with heart disease (29%), hypertension (30%), flank ecchymoses (57%), and pulsatile abdominal mass (24%). Increased intraoperative and overall mortality rates were associated with preoperative hypotension (39%, 78%) and BUN levels higher than 30 mg/dl (47%, 82%). Increased overall mortality rates were associated with creatinine levels higher than 3 mg/dl (71%) and a hematocrit of 30.0 to 32.5 vol% (75%) (P less than 0.05). Seven intraoperative factors were identified as predictors of mortality. Increased postoperative mortality rates were associated with a duration of operation of more than 400 minutes (100%), hypotension lasting longer than 110 minutes (88%), estimated blood loss more than 11,000 ml (75%), blood transfusion more than 17 U (68%), fluid administration in excess of 7000 ml (70%), and a blood pressure lower than 100 mm Hg at the conclusion of the operation (88%). Cardiac arrest was associated with increased intraoperative and overall mortality rates (77%, 82%) (P less than 0.05). In general these factors cannot be controlled by the surgeon, and future significant reduction in the operative mortality rate may be possible. These findings support the general concept of aggressive elective resection of abdominal aortic aneurysms.

Aged↗
PubMed2004

Adolescents in mid-sized and rural communities: foregone care, perceived barriers, and risk factors.

PURPOSE: To investigate the perceived health care needs, foregone care, barriers to care, and associated risk factors in a non-urban population of adolescents. METHODS: Tenth-grade students attending school and 15-17-year-old youth not attending school in a Midwestern county were surveyed or interviewed. Eighty-six percent provided usable data (n = 1948, 134 of whom were not in school). Nine focus groups (71 participants; 28 were not in school) were conducted in follow-up. Quantitative analysis included descriptive statistics, factor analysis, and logistic regression. Qualitative analysis of taped focus groups identified themes and interpreted findings. RESULTS: Although 91% had seen a physician in the past 2 years, 44% reported foregoing needed care in the last year. Barriers for specific health needs were: cost of care and lack of insurance coverage for injuries and illnesses; lack of knowledge, distrust, and stigma for depression; embarrassment and transportation for birth control and sexually transmitted infections (STIs); and not knowing where or how to access care for drug and alcohol use. Youth most likely to have foregone care included those involved with dangerous activities under peer pressure (1.8, CI: 1.44-2.13), sexual intercourse (1.4, CI: 1.25-1.67), marijuana use (1.4, CI: 1.17-1.67), anticipating parenthood before age 20 years (1.2, CI: 1.04-1.33), male gender (2.5, CI: 1.89-2.86) and perceiving good health (1.7, CI: 1.45-1.85). CONCLUSIONS: Nearly half of this non-urban population (both in and out of school) reported foregoing needed care in the last year. The barriers to care include lack of information, lack of access, poor insurance coverage, parenting issues, and concern about confidentiality.

Adolescent↗