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Results for “Analysis of Variance”

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PubMed1998

[The usefulness of abdominal echography in the diagnosis of extrapulmonary tuberculosis in patients with HIV infection].

BACKGROUND: The aim of the present study was to analyze the diagnostic profitability of echography as an indicator of extrapulmonary tuberculosis in patients with HIV infection. PATIENTS AND METHODS: HIV positive patients presenting fever of long duration were prospectively studied with an active search for specific echographic lesions. Descriptive statistics were performed by variance analysis. The diagnostic profitability of echography was evaluated by the calculation of sensitivity, specificity, positive predictive values (PPV) and negative predictive value (NPV). RESULTS: Criteria of prolonged fever was fulfilled by 116 patients. Thirty-five (30.2%) presented specific echographic alterations: 12 had multiple hyoechoic splenic lesions (34.3%), 11 abdominal adenopathies (31.4%), 9 splenic lesions and adenopathies (25.7%) and 3 showed hepato-splenic involvement and adenopathies (8.6%). The final diagnoses of these patients were: one case of toxoplasmosis, 2 MAI infection, 7 with no definitive diagnosis, and 25 (71.4%) tuberculosis. The mean CD4 lymphocyte count was 46.6 x 10(6)/L in patients with tuberculosis with no echographic findings, with a statistically significant difference of p < 0.05. The appearance of some echographic alterations had a global sensitivity of 37.3%, a specificity of 79.6% a PPV of 0.65 and a NPV of 0.51. The isolated findings of hypoechoic splenic lesions showed a sensitivity of 19.23%, a specificity of 95.12%, a PPV of 0.83 and a NPV of 0.47. CONCLUSIONS: The presence of multiple hypoechoic splenic lesions showed an elevated specificity, being greater than 95%, making this finding, although infrequent, that of greatest diagnostic profitability in the echographic study of tuberculosis. We therefore consider abdominal echography to be of great usefulness in the evaluation of patients with HIV infection and prolonged fever since the presence of these lesions, in the most severely immunosuppressed patients, may strongly suggest the diagnosis of extrapulmonary tuberculosis.

Abdomen↗
PubMed1976

In vitro determination of unbound and total iron-binding capacity in serum by radioiron using a new ion exchange strip.

A simplified method for the in vitro determination of TIBC and UIBC in serum using 59Fe was subjected to quality control in the laboratory and clinically studied in duplicate determinations of 185 sera of an unselected patient population. The data obtained were investigated by statistical means (regression, correlation, variance analysis). The precision of the method was evaluated step by step. The results indicate that the radiochemical determination of TIBC values is equivalent to the "indirect" one (UIBC + SI) as far as accuracy is concerned. Advantages of the radiochemical method are discussed.

Humans↗
PubMedDate not supplied

[Energy and nutrient consumption in Mexican women in reproductive age].

OBJECTIVE: To analyze energy and nutrient consumption in Mexican women from 12 to 49 years of age. MATERIAL AND METHODS: Dietetic information was gathered by a 24 h recall from 9,101 women who participated in the National Nutrition Survey conducted in 1988. These data were compared with sociodemographic and physiologic characteristics. Nutrient consumption was compared with the Recommended Daily Allowances (RDA). Variance analysis and t-test were used to evaluate group differences. RESULTS: Mean energy consumption was 1,721 kcal per day. The diet consisted of 15% protein, 60% carbohydrates and 25% fat. The proportion of women with dietary intakes lower than 50% of the RDA was 70% for vitamin A, 75% for vitamin B6, 56% for vitamin C, 33% for vitamin B12, 69% for folate, 33% for calcium and 22% for iron. CONCLUSION: Results show important deficiencies in the diet, predominantly in pregnant and lactating women, in women from low socioeconomic levels and in rural and indigenous women of south of the Mexican republic.

Adolescent↗
PubMed1997

Mandible measurements in aspect of some muscles attachment.

The paper deals with a part of anatomical research in aspect of clinical evaluation of lowering mandible muscles attachments (mylohyoid m, digastric m, geniohyoid m.) and genioglossus muscle. The research was conducted on 183 adult males and 117 females crania. The variance analysis of Tukey's revealed, that crania traits established on the basis of statistical parameters of breadth-length index, and visceral cranium height-breadth index, are significant. In order to establish statistical characteristics of examined traits, including into research sexual dimorphism and bilateral differences is also very important.

Adult↗
PubMed1998

[Functional decoupling of left ventricular beta-adrenoceptor in a canine model of obesity-hypertension].

OBJECTIVE: To assess cardiac beta-adrenoceptors (beta-AR) in an obesity-hypertension model. METHODS: Six male beagle dogs (aged 35 +/- 5 months) receiving during 30 weeks a high-fat diet with 60% uncooked beef fat were compared to 6 normal beagle dogs. With right auricular and left ventricular samples we analysed cardiac beta-AR density through binding study using [125I]-cyanopindolol. beta 1 and beta 2 densities were obtained by competition with CGP 20712A. Affinity state of beta-AR was assessed by competition with isoproterenol. Noradrenaline plasma level was assayed by HPLC. Left ventricular mass (LV mass) was measured by echocardiography. Results are expressed as mean +/- SE. All comparisons were performed using a variance analysis (*: p < 0.05). RESULTS: Systolic blood pressure was significantly higher in obesses (245 +/- 8 vs 197 +/- 10 mmHg in controls). Diastolic blood pressure did not differed between both groups (93 +/- 3 vs 84 +/- 3 mmHg in controls). Noradrenaline plasma levels were similar in both groups (276 +/- 30 vs 235 +/- 50 pg/mL in controls). Obesses were characterized by higher LV mass (80 +/- 24 vs 67 +/- 15 g in controls*). Right auricular and left ventricular beta-AR densities were not different in obesses (57 +/- 6 and 67 +/- 4 fmoles/mg protein) and in controls (68 +/- 7 and 63 +/- 9 fmoles/mg protein). The beta 1-AR proportion was the same in obesses and controls in right auricule (63 +/- 4 vs 64 +/- 3% in controls) and left ventricule (59 +/- 3 vs 60 +/- 4% in controls). The proportion of beta-AR receptors in a high affinity state was similar in right auricular samples (69 +/- 4 vs 67 +/- 3%) in controls) but was significantly different in left ventricule (28 +/- 6 vs 74 +/- 6%) in controls). CONCLUSION: Left ventricular beta-adrenoceptors came under a specific desensibilisation independent of plasma noradrenaline levels. This functional decoupling of beta-adrenoceptors may account for the progressive systolic dysfunction of hypertensive cardiomyopathy.

Animals↗
PubMed1994

[Anatomy and morphometry of Physa cubensis Pfeiffer, 1839 (Pulmonata: Physidae) in Cuba].

The anatomic description of Physa cubensis, based on specimens collected in 5 different sites in Cuba, is presented. The anatomic characteristics of the reproductive system as well as mantle digitations give ground for affirming that this is a unique species with external morphological variations and thus it should be kept under the Physa genre. Besides, dispersion diagrams and regression lines of the length in the width were analyzed in the five sites; the L/A (length/width) variation quotient was compared using a variance analysis. Significant differences were observed in the different sites probably due to the feeding sources of each biotope.

Animals↗
PubMed1998

A career path in clinical pathways.

Much like the development of a clinical path, the creation of a career path requires knowledge of patterns of behavior, needs for standardized education and skill development, along with variance analysis and individualized care. This nationally known nursing entrepreneur tells the story of her involvement in the development of case management and clinical pathways and how she turned that into a successful business that has changed how patient care is managed nationally and internationally.

Career Choice↗
PubMed1998

[A new method for evaluation of the antagonistic action of bacterial lactic acid (LAB) on selected pathogenic indicator bacteria].

A comparison was made of three methods: paper disc, double layer and a newly proposed agar slab techniques for testing antibacterial activity of Lactobacillus strains. Strains of indicator bacteria were selected from important pathogens of the human alimentary and genitourinary tract. The agar slab method, which is based on applying of slabs of MRS agar with overnight growth of the antagonistic bacteria to the surface of appropriate agar plates seeded with indicator bacteria, appeared to be the only method suitable for testing of aerobic and anaerobic fastidious bacteria. After testing of 27 Lactobacillus strains against 3 selected indicator bacteria: E. coli, Salmonella enteritidis and Staphylococcus aureus, calculating mean values and standard deviations for diameters of inhibitory zones and making variance analysis it was shown that in comparison to other methods the agar slab technique, although less sensitive than others, gave most consistent and reproducible results.

Digestive System↗
PubMed2002

Are isochore sequences homogeneous?

Three statistical/mathematical analyses are carried out on isochore sequences: spectral analysis, analysis of variance, and segmentation analysis. Spectral analysis shows that there are GC content fluctuations at different length scales in isochore sequences. The analysis of variance shows that the null hypothesis (the mean value of a group of GC contents remains the same along the sequence) may or may not be rejected for an isochore sequence, depending on the subwindow sizes at which GC contents are sampled, and the window size within which group members are defined. The segmentation analysis shows that there are stronger indications of GC content changes at isochore borders than within an isochore. These analyses support the notion of isochore sequences, but reject the assumption that isochore sequences are homogeneous at the base level. An isochore sequence may pass a homogeneity test when GC content fluctuations at smaller length scales are ignored or averaged out.

Analysis of Variance↗
PubMed2005

Univariate and bivariate variance component linkage analysis of a whole-genome scan for loci contributing to bone mineral density.

Osteoporosis is a common condition characterized by reduced skeletal strength and increased susceptibility to fracture. The single major risk factor for osteoporosis is low bone mineral density (BMD) and strong evidence exists that genetic factors are in part responsible for an individual's BMD. A cohort of 40 multiplex Caucasian families selected through a proband with osteoporosis was genotyped for microsatellite markers spaced at an average of 10 cM, and linkage to femoral neck (FN), lumbar spine (LS) and trochanter (TR) BMD was analyzed using univariate and bivariate variance component linkage analysis. Maximum univariate multipoint lod-scores were 2.87 on chromosome 1p36 for FN BMD, 1.89 on 6q27 for TR BMD, and 2.15 on 7p15 for LS BMD. Results of bivariate linkage analysis were highly correlated with those of the univariate analysis, although generally less significant, suggesting the possibility that some of these susceptibility loci may exert pleiotropic effects on multiple skeletal sites.

Analysis of Variance↗
PubMed2001

Adolescent substance use and sexual risk-taking behavior.

PURPOSE: To examine the relationship of adolescent substance use and dependence to sexual risk-taking behavior in late adolescence and young adulthood. METHODS: We prospectively examined self-reported sexual behaviors and substance involvement questionnaires in a sample of youth in substance abuse treatment programs and a comparison sample of sociodemographically similar community youths without histories of substance use disorders recruited from media ads. Assessments of sexual behaviors and substance involvement (78% white, 51% female) were collected at 2, 4, and 6 years after initial assessments, as they transitioned from middle adolescence to young adulthood (from age 15.5 to age 21.5 years, on average). The two samples were compared using Chi-square, analysis of variance, and multivariate analysis of variance approaches. Continuous indicators of high-risk sexual behaviors and substance involvement were analyzed with multiple regression. RESULTS: Earlier age of onset to sexual activity, more sexual partners, less consistent use of condoms, more sexually transmitted diseases (STDs), and greater prevalence of human immunodeficiency virus testing were reported by youth in the clinical treatment sample relative to sociodemographically comparable nonabusing community youth. High rates of STDs were found among females, and more substance-abusing females reported pregnancies than community females. Substance involvement continued to be associated with high-risk sexual behavior throughout the transition into young adulthood. CONCLUSIONS: Youth identified with substance problems are more likely to engage in risky sexual behaviors during adolescence and to continue risky sexual behaviors to the extent that substance problems persist. Risk reduction education should be included with adolescent substance abuse treatment.

Adolescent↗
PubMed1994

Analysing cross-sectional anthropometric data.

This paper provides a detailed account, with examples, of the types of statistical analyses which can be carried out on cross-sectional anthropometric data. For continuous characters the analyses described cover t-tests, one-way analysis of variance, more complex analysis of variance with covariates; testing for curvilinearity; regression analysis and multiple regression analysis. For discrete characters the analyses include chi-square, odds ratios, sensitivity and specificity, logistic regression and discriminant analyses.

Anthropometry↗
PubMed1993

Effect of antipsychotic withdrawal on extrapyramidal symptoms: statistical methods for analyzing single-sample repeated-measures data.

Using symptom severity ratings of extrapyramidal side effects (EPS) during a 4-week antipsychotic washout period, we illustrate particular problems associated with repeated measures of symptom severity and demonstrate four analysis methods. The often suggested analysis of variance and multivariate analysis of variance found no mean change in weekly Simpson Angus scores over the 4-week washout despite the fact that 43% had clinically significant EPS prior to drug discontinuation. On the other hand, the Friedman Analysis of Ranks and Cochran-Mantel-Haenszel (CMH) statistics found significant change over the washout period. These two less well-known techniques place fewer restrictions on the data, can be more sensitive to patterns of change, and may be more appropriate for psychiatric data. The CMH method is particularly attractive since it does not require complete data on all subjects as do many other techniques. This minimizes the number of cases lost to missing data and increases the generality of the results.

Adult↗
PubMed2001

Spinal movement and performance of a standing reach task in participants with and without Parkinson disease.

BACKGROUND AND PURPOSE: Evidence suggests that individuals with early and mid-stage Parkinson disease (PD) have diminished range of motion (ROM). Spinal ROM influences the ability to function. In this investigation, the authors examined available spinal ROM, segmental excursions (the ROM used) during reaching, and their relationships in community-dwelling adults with and without PD. SUBJECTS: The subjects were 16 volunteers with PD (modified Hoehn and Yahr stages 1.5-3) and 32 participants without PD who were matched for age, body mass index, and sex. METHODS: Range of motion of the extremities was measured using a goniometer, and ROM of the spine was measured using the functional axial rotation (FAR) test, a measure of unrestricted cervico-thoracic-lumbar rotation in the seated position. Motion during reaching was determined using 3-dimensional motion analysis. Group differences were determined using multivariable analysis of variance followed by analysis of variance. Contributions to total reaching distance of segmental excursions (eg, thoracic rotation, thoracic lateral flexion) were determined using forward stepwise regression. RESULTS: Subjects with PD as compared with subjects without PD had less ROM (FAR of 98.2 degrees versus 110.3 degrees, shoulder flexion of 151.9 degrees versus 160.1 degrees) and less forward reaching (29.5 cm versus 34.0 cm). Lateral trunk flexion and total rotation relative to the ground contributed to reaching, with the regression model explaining 36% of the variance. DISCUSSION AND CONCLUSION: These results contribute to the growing body of evidence demonstrating that spinal ROM is impaired early in PD.

Adult↗
PubMed1996

Black grandparents: curriculum development.

The performance of Black grandparents was examined to determine the most suitable content for an educational program intended to assist them in their role. A sample of 626 non-consanguineous subjects included 204 grandparents, 128 parents, and 294 grandchildren. Each generation group completed a separate version of the Grandparent Strengths and Needs Inventory to identify the favorable qualities of grandparents and aspects of their relationships in which further growth was necessary. A combination of multivariate analysis of variance procedures, univariate analysis of variance tests, and t-tests were used to analyze scores, confirm results, and assist with interpretation of data. All groups described aspects of grandparents success and made known specific realms of learning that grandparents should acquire in order to become more effective. Analysis of the responses revealed significant main effects for generation, gender of grandchild, age of grandchild, and amount of time that grandparent and grandchild spent together. Considerations were identified for improving grandparent influence and guiding the development of grandparent education programs.

Adolescent↗
PubMed2000

Comparison of first ray dorsal mobility among different forefoot alignments.

STUDY DESIGN: Experimental design using 1-way analysis of variance and regression analysis to test the influence of 3 forefoot alignments on the dorsal mobility of the first ray. OBJECTIVES: To determine the effect of forefoot alignment on the magnitude of first ray dorsal mobility to an imposed load and to describe any association between forefoot alignment and age on dorsal mobility of the first ray. BACKGROUND: Instability of the first ray has been implicated as a primary mechanical etiology of many foot problems. It has been proposed that a relationship exists between forefoot alignment and mobility of the first ray, with a varus aligned forefoot contributing to the development of an unstable first ray. METHODS AND MEASURES: Sixty female (n = 34) and male (n = 26) subjects aged 18-77 were assigned into valgus, neutral, and varus foot groups (20 per group) based on a clinical measurement of forefoot alignment. A load cell device measured dorsal mobility of the first ray under a standard load of 55 N. Within-day repeat measures were taken from a subsample of subjects. In addition to reliability analysis, analysis of variance and regression analyses tested the relationship between forefoot alignment, age and sex, and mobility of the first ray. RESULTS: The forefoot valgus group demonstrated significantly less dorsal mobility of the first ray than neutral or varus groups. The varus and neutral groups were not significantly different from one another. Forefoot alignment and sex were significant linear predictors (R2 = 0.40) of first ray dorsal mobility. Age had no significant association to dorsal mobility of the first ray. CONCLUSION: Subjects having a valgus aligned forefoot had less dorsal excursion of the first ray than subjects having a neutral aligned forefoot. This investigation provides evidence supporting a relationship between forefoot alignment and mobility of the first ray.

Adolescent↗
PubMed2001

Variance component linkage analysis indicates a QTL for femoral neck bone mineral density on chromosome 1p36.

Osteoporosis is a common condition characterized by reduced skeletal strength and increased susceptibility to fracture. Eight million Americans over the age of 50 have osteoporosis of the femoral neck. The most important risk factor for osteoporosis is low bone mineral density (BMD), and several epidemiological studies have shown the importance of genetic factors in determining variability of BMD. An initial genome screen in seven large pedigrees suggested that a candidate region conferring susceptibility to low BMD of the femoral neck was located on chromosome 1p36. We have now confirmed and extended this finding by analyzing nine microsatellite markers spanning a 40 cM interval across the candidate region in an expanded sample of 42 families. Heritability of femoral neck BMD was estimated as 0.51 +/- 0.13 in these families, after accounting for the effects of age, sex, body mass index, height and weight. Variance component linkage analysis yielded a maximum multipoint LOD score of 3.53 for linkage of femoral neck BMD to a quantitative trait locus (QTL) located near marker D1S214. The associated empirical P-value by simulation analysis was equal to 0.0001. The results strongly support the hypothesis that a major QTL controlling femoral neck BMD is located on chromosome 1p36.2-p36.3, and further analysis of candidate genes in this region is warranted.

Adolescent↗
PubMed1986

Chronic 60-Hz electric field exposure-induced subtle bioeffects on hematology.

The effects of 120 days of high-intensity (80-kV/m) 60-Hz electric field exposure on hematologic constituents were investigated using a three-generation design including 135 field-exposed and 135 sham-exposed male Sprague-Dawley rats. Statistical tests performed included the multivariate analysis of variance, the univariate analysis of variance, and tests of simple effects. Total white cell count, lymphocyte count, and eosinophil count were significantly lower in field-exposed subjects; however, none of the red cell parameters differed significantly. The observed hematologic variations related to the exposure of a high-intensity electric field are consistent with those observed in animals responding to a mild stressor.

Analysis of Variance↗