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PubMed1986

Directly observed relations in complete galaxy samples and the predictions of redshift-distance power laws.

Directly observed relations in complete galaxy samples (apparent magnitude or diameter vs. redshift) are compared with the predictions of redshift-distance power laws. The predictions are obtained by an objective, nonparametric, statistically uniform, and fully reproducible procedure. In all cases the linear law fits even more poorly than a cubic law, and the optimal law is approximately quadratic. Even a 1.2 power law is conspicuously better-fitting than a linear law. The results of the present study in terms of directly measured quantities are consistent with and confirm earlier studies in terms of theoretical quantities such as absolute magnitudes and diameters. They show that there is no positive evidence for the Hubble law in manifestly fair galaxy samples and that the law can be reconciled with the data in complete samples only, if at all, by the adjunction of a tissue of ancillary hypotheses, none of which is capable of direct observational substantiation.

Journal Article↗

PubMed1997

Volatile signals of the major histocompatibility complex in male mouse urine.

Variation in the genes of the major histocompatibility complex (MHC) contributes to unique individual odors (odortypes) in mice, as demonstrated by the ability of trained mice in a Y-maze olfactometer to discriminate nearly identical inbred mice that differ genetically only at the MHC (MHC congenic mice), while they cannot distinguish genetically identical inbred mice. Similar distinctions are possible with urine, a substance that is involved in many facets of mouse chemical communication. This paper reports results supporting the hypothesis that the MHC-determined urinary odor is composed of a mixture of volatile carboxylic acids occurring in relative concentrations that are characteristic of the odortype. Y-maze behavioral testing of urine fractions from anion exchange chromatography indicates that volatile acids are necessary and sufficient to convey MHC odortype information. Diethyl ether extracts, which are expected to contain the more volatile, less polar organic acids, were also discriminable in the Y-maze olfactometer. Ether extracts of 12 different urine samples from each of two panels of MHC congenic mice were analyzed by gas chromatography. No compounds unique to urine of either genotype were detected, but compounds did appear to occur in characteristic ratios in most of the samples of each type. Nonparametric statistical analysis of the gas chromatographic data showed that eight of the peaks occurred in significantly different relative concentrations in the congenic samples. One of the peaks was shown to represent phenylacetic acid, which has implications for the mechanism of the MHC specification of odortype.

Animals↗

PubMed2006

Decrease of pregnant women's pelvic pain after acupuncture: a randomized controlled single-blind study.

BACKGROUND: The efficacy of acupuncture on low-back and/or pelvic pain in late pregnancy is reviewed in few reports. Our aim was to evaluate the effects of two different acupuncture stimulation modes on pelvic pain intensity and some emotional symptoms due to the pain condition. METHODS: In a prospective randomized controlled single-blind study, pregnant women with pelvic pain, median gestational age 26 weeks (range 18-35), were given 10 acupuncture treatments. Needles were inserted subcutaneously over acupuncture points without further stimulation (superficial, n=22), or intramuscular and stimulated repeatedly until a perceived sensation of numbness, de qi, (deep, n=25). Self-reported pain intensity at rest and during daily activities was assessed on a visual analog scale. The variables pain, emotional reactions, and loss of energy were assessed according to the Nottingham Health Profile questionnaire. Changes in assessed variables were analyzed with a nonparametric statistical method allowing for analysis of systematic group changes separated from additional individual changes. RESULTS: After acupuncture stimulation, significant systematic group changes towards lower levels of pain intensity at rest and in daily activities as well as in rated emotional reaction and loss of energy were seen. The results also showed additional individual changes in most variables. In this study, no differences between the effects induced by the superficial and deep acupuncture stimulation modes were observed. CONCLUSION: Acupuncture stimulation that is individually designed may be a valuable treatment to ameliorate suffering in the condition of pelvic pain in late pregnancy.

Activities of Daily Living↗

PubMed2006

EMG biofeedback versus topical lidocaine gel: a randomized study for the treatment of women with vulvar vestibulitis.

BACKGROUND: To evaluate the efficacy of electromyographic biofeedback and topical lidocaine treatment for women with vulvar vestibulitis. METHODS: A prospective randomized study where 46 women with vulvar vestibulitis were randomized to receive either electromyographic biofeedback or topical lidocaine treatment for four months. Assessments with vulvar pressure pain thresholds and questionnaires regarding quality of life, psychosocial adjustments, and sexual functioning were made before treatment, after treatment, and at six- and 12-month follow-ups. Nonparametric statistical methods were used to analyze differences in outcomes. RESULTS: Nine women (9/46) dropped out during the treatment period. Both treatments showed significantly improved values for vestibular pressure pain thresholds, quality of life measurements, and sexual functioning at the 12-month follow-up. No differences were found between the two treatment groups. No severe side effects were reported. CONCLUSIONS: Four months' treatment with electromyographic biofeedback and topical lidocaine gave statistically significant improvements on vestibular pain measurements, sexual functioning, and psychosocial adjustments at the 12-month follow-up. No differences in outcome between the two treatments were observed but a larger sample may be needed to obtain significance. The treatments were well tolerated but the compliance to the electromyographic biofeedback training program was low. A combination of both treatments could potentially benefit many women with vulvar vestibulitis.

Adaptation, Psychological↗

PubMedDate not supplied

Effect of vitamin E and ozone on pentane and ethane expired by rats.

Pentane and ethane, which arise during lipid peroxidation in vivo, were measured by gas chromatography in breath samples of rats fed for 8 weeks a vitamin E-deficient diet to which had been added 0, 11, or 40 IU vitamin E acetate per kg. Further lipid peroxidation was induced by exposure of individual rats to 1 ppm ozone for 60 min. Nonparametric statistical analysis of the data for pentane expired before exposure of rats to ozone gave alpha values (alpha = 2P) of 0.006 when the O vitamin E group was compared with either of the vitamin E-supplemented groups. For ethane, comparison of the O vitamin E group with the groups supplemented with 11 and 40 IU vitamin E/kg of diet were 0.0294 and 0.0080, respectively. Alpha values less than .05 were considered significant. After a 60-min exposure of rats to 1 ppm ozone, the paired t-test showed pentane to be significantly (P less than .005) increased in only the rats fed the vitamin E-deficient diet.

Animals↗

PubMed1994

Are age and ethics related?

Ethical values of 171 college students at California State University, Chico, were measured, using a subset of the Rokeach (1968, 1971) Value Survey. Nonparametric statistical analysis, four value measures, and four different consistent tests of significance and probability showed, surprisingly, that the younger students were more ethical than the older students. College students under 21 scored significantly higher ethically on three out of the four measures. Younger college students valued equality, freedom, and honesty more than their older classmates did. Surprisingly also, the younger students were significantly more concerned with being helpful and intellectual and were less involved in pursuing an exciting life and in social recognition than were the older students.

Adult↗

PubMed1996

TMD diagnostic decision-making and probability theory. Part I.

This article is an educational analysis and discussion of some recently proposed diagnostic criteria, diagnostic methods, and diagnostic decision processes, pertaining specifically to temporomandibular disorders (TMD). On the basis of a discussion of classic probability theory, classic measurement theory, and examples using nonparametric inferential statistical tests, it is suggested that certain TMD diagnostic criteria and methods, and their associated decision matrix, favor subjective clinical opinions (largely pseudoscientific observations) and arbitrary clinical indices rather than objective scientific facts.

Binomial Distribution↗

PubMed1996

TMD diagnostic decision-making and probability theory. Part II.

As it specifically pertains to temporomandibular disorders (TMD), this article is an educational analysis and discussion of some recently proposed diagnostic criteria, diagnostic methods, and diagnostic decision processes. On the basis of a discussion of classic probability theory, classic measurement theory, and examples using nonparametric inferential statistical tests, it is suggested that certain TMD diagnostic criteria and methods, and their associated decision matrix, favor subjective clinical opinions (largely pseudoscientific observations) and arbitrary clinical indices rather than objective scientific facts.

Data Interpretation, Statistical↗

PubMed1996

Vehicle occupants' exposure to aromatic volatile organic compounds while commuting on an urban-suburban route in Korea.

This study identified in-auto and in-bus exposures to six selected aromatic volatile organic compounds (VOCs) for commutes on an urban-suburban route in Korea. A bus-service route was selected to include three segments of Taegu and one suburban segment (Hayang) to satisfy the criteria specified for this study. This study indicates that motor vehicle exhaust and evaporative emissions are major sources of both auto and bus occupants' exposures to aromatic VOCs in both Taegu and Hayang. A nonparametric statistical test (Wilcoxon test) showed that in-auto benzene levels were significantly different from in-bus benzene levels for both urban-segment and suburban-segment commutes. The test also showed that the benzene-level difference between urban-segment and suburban-segment commutes was significant for both autos and buses. An F-test showed the same statistical results for the comparison of the summed in-vehicle concentration of the six target VOCs (benzene, toluene, ethylbenzene, and o,m,p-xylenes) as those for the comparison of the in-vehicle benzene concentration. On the other hand, the in-vehicle benzene level only and the sum were not significantly different among the three urban-segment commutes and between the morning and evening commutes. The in-auto VOC concentrations were intermediate between the results for the Los Angeles and Boston. The in-bus VOC concentrations were about one-tenth of the Taipei, Taiwan results.

Air Pollutants↗

PubMedDate not supplied

Prehospital 12-lead ECG: efficacy or effectiveness?

INTRODUCTION: Previous literature has documented that prehospital 12-lead electrocardiography (ECG) decreases the time to reperfusion in patients with an acute ST-segment elevation myocardial infarction (STEMI). OBJECTIVE: To compare time to ECG, time to angioplasty suite (laboratory), and time to reperfusion in emergency medical services (EMS) STEMI patients, who received care through three different processes. METHODS: The setting was a large suburban community teaching hospital with emergency department (ED)-initiated single-page acute myocardial infarction (AMI) team activation for STEMI patients. The population was STEMI patients transported by EMS from January 2003 to October 2005. Not all EMS agencies had prehospital 12-lead ECG capability. Paramedics interpret and verbally report clinical assessment and ECG findings via radio. The AMI team is activated at the discretion of the emergency physician 1) before patient arrival to the ED based on EMS assessment, 2) after ED evaluation with EMS ECG, or 3) after ED evaluation and ED ECG. Time intervals were calculated from ED arrival. To assess the impact of interventions on performance targets, we also report the proportion of patients who arrived in laboratory within 60 minutes and reperfusion within 90 minutes of arrival. Parametric and nonparametric statistics are used for analysis. RESULTS: During the study period, there were 164 STEMI patients transported by EMS; mean age was 66.1 years, and 56% were male. Of these, 93 (56.7%) had an EMS ECG and 31 (33%) had AMI team activation before ED arrival. Mean time to laboratory for all patients was 49.8 +/- 34.4 minutes and time to reperfusion was 93.2 +/- 34.5 min. Patients with prearrival activation were transported to laboratory sooner (mean, 24.3 vs. 53. 4 minutes; p < 0.001) and received reperfusion sooner than all other patients (mean, 70.4 vs. 96.3 minutes; p = 0.007). More prearrival activation patients met performance targets to laboratory (96.7% vs. 73.7%; p = 0.009) and reperfusion (85.2% vs. 51.0%; p = 0.003). There was no difference in time to laboratory or to reperfusion for patients who received EMS ECG but no prearrival activation compared with those who received EMS transport alone. CONCLUSIONS: A minority of patients with EMS ECGs had prearrival AMI team activation. EMS ECGs combined with systems that activate hospital resources, but not EMS ECGs alone, decrease time to laboratory and reperfusion.

Aged↗

PubMed2006

Funisitis in term pregnancy is associated with microbial invasion of the amniotic cavity and intra-amniotic inflammation.

OBJECTIVE: Funisitis is the histologic counterpart of the fetal inflammatory response syndrome, which is a multisystemic disorder associated with impending preterm delivery and adverse neonatal outcome. The purpose of this study was to examine the relationship between funisitis and the microbiologic status of amniotic fluid (AF) and AF white blood cell (WBC) count in patients at term. METHODS: The relationship between the presence of funisitis, AF culture, and AF WBC count was examined in 832 consecutive patients who delivered a term neonate within 72 hours of amniocentesis. AF was cultured for aerobic and anaerobic bacteria, as well as for mycoplasmas. Funisitis was diagnosed in the presence of neutrophil infiltration into the umbilical vessel walls or Wharton's jelly. AF WBC count was analyzed in a hemocytometer chamber. Nonparametric statistics were used for data analysis. RESULTS: Funisitis was present in 4% (30/832) of cases. A positive AF culture was more common in cases with funisitis than in those without funisitis (17% vs. 5%; p < 0.05). Patients with funisitis had a significantly higher median AF WBC count than those without funisitis (median >1000 cells/mm3 vs. median 2 cells/mm3; p < 0.001). The frequency of funisitis and of a positive AF culture was 1% in women without labor and with intact membranes and the frequencies and the median AF WBC count increased in the presence of labor or rupture of membranes. CONCLUSION: Funisitis is present in 4% of women at term and is associated with microbial invasion of the amniotic cavity (MIAC) and inflammation as reflected by increased AF WBC count.

Adult↗

PubMed2001

Evidence for a language quantitative trait locus on chromosome 7q in multiplex autism families.

Autism is a syndrome characterized by deficits in language and social skills and by repetitive behaviors. We hypothesized that potential quantitative trait loci (QTLs) related to component autism endophenotypes might underlie putative or significant regions of autism linkage. We performed nonparametric multipoint linkage analyses, in 152 families from the Autism Genetic Resource Exchange, focusing on three traits derived from the Autism Diagnostic Interview: "age at first word," "age at first phrase," and a composite measure of "repetitive and stereotyped behavior." Families were genotyped for 335 markers, and multipoint sib pair linkage analyses were conducted. Using nonparametric multipoint linkage analysis, we found the strongest QTL evidence for age at first word on chromosome 7q (nonparametric test statistic [Z] 2.98; P=.001), and subsequent linkage analyses of additional markers and association analyses in the same region supported the initial result (Z=2.85, P=.002; chi(2)=18.84, df 8, P=.016). Moreover, the peak fine-mapping result for repetitive behavior (Z=2.48; P=.007) localized to a region overlapping this language QTL. The putative autism-susceptibility locus on chromosome 7 may be the result of separate QTLs for the language and repetitive or stereotyped behavior deficits that are associated with the disorder.

Autistic Disorder↗

PubMed2000

Efficacy and safety findings from naturalistic fluoxetine drug treatment in adolescent and young adult patients.

This article reports on the efficacy and safety of the selective serotonin reuptake inhibitor, fluoxetine, in 213 patients (ages 11-23 years) treated by psychiatrists/neurologists (PN) or general practitioners/internists (GPI). Data were derived from naturalistic drug utilization observation (DUO) studies with fluoxetine (n = 18,759 patients). Data collection--at the start and the end of the observation period (< or =6 weeks)--included patient characteristics, diagnoses, medication, co-medication, efficacy, and adverse events (AEs). Nonparametric statistics and descriptive p values (two-tailed) were used. Analyses revealed various differences between PN (n = 56) and GPI (n = 157) samples as to patient and treatment characteristics (p < 0.001-0.08). Based on both Clinical Global Impression (CGI; all p < 0.001) and self-assessment (total n = 47; Zung SDS, all p < or = 0.003), both PN and GPI patients showed improvements in their symptomatology over time, including suicidality (all p < 0.001; there were no group differences). Overall AE rates were higher in PN patients (p < 0.01; 17.9% vs. 4.5%); the frequency and type of AEs in both subgroups were typical for fluoxetine and the total DUO samples. In fact, AE rates were lower compared to controlled trials. Findings suggest that PN patients were more severely ill at observation start and suffered a more complicated treatment course. However, clinical efficacy showed highly significant improvements in both subgroups; AE rates were low in both--although higher in PN patients. Thus, results support a positive benefit/risk ratio of fluoxetine use for this young patient population.

Adolescent↗

PubMed2004

A simple post hoc transformation that improves the metric properties of the BBB scale for rats with moderate to severe spinal cord injury.

The Basso, Beattie, Bresnahan (BBB) open field locomotor scale is a popular measure of functional recovery following spinal cord injury (SCI). To examine the metric properties of the scale, we performed detailed analyses of BBB scores from 643 rats with moderate and severe SCI (12.5, 25, or 50 mm MASCIS) from two different laboratories. The analyses revealed that the BBB scale is ordinal in the most frequently used portion of the scale. Higher scores (14 and greater) were not frequently assigned in the dataset as animals with mild injuries were not sampled, making the ordinal nature of the upper end of the scale difficult to assess. The rare scores assigned in this range disproportionately increased variance. Under these conditions collapsing scores above 14 into one category increased effect size. Analysis of the lower region of the scale revealed that some scores (2 and 3) were rarely assigned, implying a discontinuity in the scale. The discontinuous nature of the lower portion of the scale presents a problem for both parametric and nonparametric statistical analyses. Pooling scores 2/3/4 eliminated the gap, enhancing the metric properties of the scale. Under the injury conditions evaluated, the transformation helped assure that the data were continuous and ordered. Further, interval durations were comparable across the entire range of the transformed scale, allowing application of parametric statistical techniques. The transformation should be applied in a post hoc fashion to reduce variability and increase power in cases where few scores fall in upper portion of the scale.

Animals↗

PubMed1998

The TEST 1 automated system: a new method for measuring the erythrocyte sedimentation rate.

We evaluated performance of the TEST 1 (SIRE Analytical Systems, Udine, Italy), a fully automated analyzer for the measurement of the erythrocyte sedimentation rate (ESR). Intra-assay reproducibility was satisfactory for a wide range of ESR values, whereas there was a significant decrease in ESR data when the samples were stored at 4 degrees C for up to 24 hours. We compared TEST 1 with the Westergren ESR method approved by the International Council for Standardization in Haematology (ICSH) and with the Diesse Ves-Matic analyzer Linear regression analysis comparing the TEST 1 and the ICSH reference method yielded satisfactory correlations for K3 EDTA- and sodium citrate-anticoagulated samples. Bland-Altman analysis showed no evidence of a systematic bias between the TEST 1 and the reference method. A close correlation was found between the TEST 1 system and the Diesse Ves-Matic analyzer despite a significant positive systematic bias. Reference values for men and women were analyzed according to nonparametric statistics. The TEST 1 was easy to use, had a satisfactory operative practicability required minimal maintenance, and reduced contact with potential biohazards. This system enables the determination of ESR with any common standard-sized tube; the use of samples anticoagulated with K3 EDTA can widely reduce the workload in clinical laboratories.

Adult↗

PubMed1979

Prognostic factors in adrenal cortical tumors. A mathematical analysis of clinical and morphologic data.

Forty-one patients with adrenal cortical tumors were evaluated retrospectively for the presence of histologic and non-histologic features associated with malignant behavior. The patients who survived operation were followed at least five years. The association of these features with subsequent metastasis was examined by both parametric and nonparametric statistical methods. Twelve criteria were statistically significant in predicting subsequent metastasis. The most significant of these were: clinical evidence of weight loss, broad fibrous bands traversing the tumor, a diffuse growth pattern, vascular invasion, tumor cell necrosis, and tumor mass. The tendency toward metastasis for each tumor was expressed in indices that correlated well with diagnoses made by conventional histologic means, but were more accurate in predicting subsequent clinical behavior than nonquantitative methods of evaluation.

Adolescent↗

PubMed2004

Association between self-monitoring of blood glucose and glycemic control in patients with type 2 diabetes mellitus.

PURPOSE: The relationship between the self-monitoring of blood glucose (SMBG) and glycemic control in patients with type 2 diabetes mellitus in a Veterans Affairs (VA) medical center was studied. METHODS: Laboratory, inpatient, outpatient, and demographic data for patients with type 2 diabetes mellitus who were seen for three years continuously or receiving their care regularly from a single Texas VA facility between October 1, 1999, and September 30, 2002, were obtained. Local pharmacy data were used to identify patients who received blood-glucosemonitoring strips. Patients were assigned to one of four mutually exclusive groups: those who did not receive monitoring strips at all, those who received strips in fiscal year (FY) 2002 only, those who received strips in FYs 2001 and 2002, and those who received strips during all three years (FYs 2000, 2001, and 2002). Frequency of monitoring and case-mix scores were measured. Nonparametric statistics were used to compare the demographic and clinical characteristics of the four groups. Robust regression was used to analyze the relationships between SMBG and glycemic control in FY 2002. RESULTS: Of the 1185 patients who received oral hypoglycemic medications during all three fiscal years, 976 patients met the criteria for inclusion in one of the four groups. There were no significant differences among the four groups in baseline hemoglobin A1c (HbA1c) values, body mass index, or case-mix scores. The Kruskal-Wallis test found no significant difference among the four groups in the number of laboratory blood glucose tests conducted, but there were significant differences in the number of HbA1c tests conducted among the groups. CONCLUSION: SMBG was not associated with glycemic control in VA patients with type 2 diabetes mellitus managed on oral hypoglycemic medications.

Aged↗

PubMed2003

Modified nonparametric approaches to detecting differentially expressed genes in replicated microarray experiments.

MOTIVATION: An important goal in analyzing microarray data is to determine which genes are differentially expressed across two kinds of tissue samples or samples obtained under two experimental conditions. Various parametric tests, such as the two-sample t-test, have been used, but their possibly too strong parametric assumptions or large sample justifications may not hold in practice. As alternatives, a class of three nonparametric statistical methods, including the empirical Bayes method of Efron et al. (2001), the significance analysis of microarray (SAM) method of Tusher et al. (2001) and the mixture model method (MMM) of Pan et al. (2001), have been proposed. All the three methods depend on constructing a test statistic and a so-called null statistic such that the null statistic's distribution can be used to approximate the null distribution of the test statistic. However, relatively little effort has been directed toward assessment of the performance or the underlying assumptions of the methods in constructing such test and null statistics. RESULTS: We point out a problem of a current method to construct the test and null statistics, which may lead to largely inflated Type I errors (i.e. false positives). We also propose two modifications that overcome the problem. In the context of MMM, the improved performance of the modified methods is demonstrated using simulated data. In addition, our numerical results also provide evidence to support the utility and effectiveness of MMM.

Algorithms↗