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PubMed2002

Is the partial Mantel test inadequate?

A publication by Raufaste and Rousset (2001) questioned the effectiveness of the partial Mantel test, a nonparametric statistical test for association among three distance matrices. By repeated simulations, we calculated the cumulative density functions of the null-hypothesis probability of no correlation, within an explicit model of causal relationships. Results do not support the criticism: in conditions of moderate correlation between the independent matrices, the actual error rate is closely associated to the intended type-I error alpha.

Computer Simulation↗

PubMed2007

A cross-sectional study evaluating the relationship between cortisol suppression and asthma control in patients with difficult asthma.

AIM: To examine the relationship between cortisol suppression and asthma symptoms in patients with difficult asthma. METHODS: Patients, referred to a specialist difficult asthma service and who fulfilled the criteria for difficult asthma, were recruited to the study in a sequential, unselected manner. At each clinic visit, all patients completed a validated asthma control questionnaire. For measuring cortisol suppression, early morning urinary cortisol [corrected for creatinine to give urinary cortisol creatinine ratio (UCC ratio)] was used. The urine samples were collected and stored at -70 degrees C until ready for analysis. Urinary cortisol was extracted (solid-phase extraction) and analysed using high-performance liquid chromatography. The Pearson correlation coefficient was used for correlation analysis while t-tests were used for between-group differences for normally distributed data. If the data were not normally distributed, nonparametric statistics were used. A P-value < 0.05 was considered statistically significant. RESULTS: During the study period all the patients who attended the difficult asthma clinic and fulfilled the criteria for difficult asthma (n = 66) agreed to take part in the study. There were moderate to strong and significant associations between several measures of asthma control and UCC ratio. The correlation coefficient with five indicators of asthma control ranged between 0.3 and 0.5 (P < 0.05). CONCLUSIONS: We have demonstrated a relationship between cortisol suppression and asthma control in difficult asthmatics on high-dose steroid therapy. We have proposed a model based on the relationship between symptom control and cortisol suppression, whereby both adherence and therapeutic adjustments could potentially be made. A properly controlled prospective clinical trial should examine the utility of this approach in clinical practice.

Adult↗

PubMed2006

The presence of dominant T-cell clones in peripheral blood of patients with collagen vascular disorders: a prospective study of 97 cases.

BACKGROUND: T-lymphocyte dysfunction has been seldom investigated in collagen vascular disorders. The search for dominant T-cell clones has been scarcely reported, although the presence of such clones might be expected in disorders showing immune responses directed against a variety of autoantigens. OBJECTIVES: We conducted a systematic search for dominant T-cell clones in peripheral blood in patients with collagen vascular disorders. Patients and methods Ninety-seven patients with collagen vascular disorders were studied (7 cutaneous and 38 systemic lupus erythematosus; 8 multiple morphea; 12 regional scleroderma; 32 systemic sclerosis of the CREST type). A dominant T-cell clone was searched for in peripheral blood by polymerase chain reaction targeting the T-cell receptor gamma chain followed by a size analysis of amplified fragments. Peripheral blood from patients with nonlymphocyte-dependent disorders and matched by age and sex was assessed in the same conditions. Results in both groups were compared using nonparametric statistical tests. RESULTS: Overall, a circulating dominant T-cell clone was found in 52% of patients compared with 16.9% in controls. More precisely, such a dominant clone was present in 43% and 37% of cutaneous and systemic lupus erythematosus, respectively, in 75% of multiple morphea, 75% of regional scleroderma and 60% of CREST syndrome patients. The percentages in all subsets of patients were significantly higher than in the control group. CONCLUSIONS: The presence of a dominant T-cell clone in peripheral blood is significantly more frequent in collagen vascular disorders than in controls, especially in patients with scleroderma, whatever the clinical subset, which suggests T-cell involvement in the immune response dysfunction in these diseases classically characterized by disturbances of B lymphocytes. The relevance of such a dominant clone regarding diagnosis, pathomechanisms, long-term outcome and visceral prognosis of these diseases as well as therapeutic decisions remains to be evaluated.

Adolescent↗

PubMed1984

A study of yoga as a nursing intervention in the care of patients with pleural effusion.

'Pranayama' or yogic breathing as a method of re-expansion of lungs in patients with pleural effusion was studied. Ten patients with pleural effusion practised alternate nostril breathing for 20 days after aspiration of fluid. An equal number matched for age and smoking habits underwent routine physiotherapy of the hospital for the same period. Lung function was measured: before aspiration; immediately after aspiration; and, 5, 10, 15 and 20 days after aspiration. The FVC, FEV1, MVV, PEFR, CE and RS, were used to measure lung function. The difference between the two groups in the gain in lung expansion as assessed by the above measures was tested for significance with appropriate nonparametric statistical tests at 0.1 level of significance. The results revealed that the patients practising Pranayama demonstrated a quicker re-expansion of the lungs in most of the measures of lung function. The findings are discussed in relation to implications for nursing care.

Adolescent↗

PubMed1991

Ovine polioencephalomalacia associated with dietary sulphur intake.

Fifty-six female crossbred two-month-old lambs were housed in individual cages, and fed a basic ration of barley (59%), soybean meal (5%), and alfalfa (32%) prepared to meet NRC nutrient requirements. Four percent of the diet contained a standard salt mix to which the factors inorganic sulphur (S) and thiamine (B1) were added. Four treatment groups were used: low sulphur and normal thiamine (0.19% S, 13.7 mg/kg B1) low sulphur and high thiamine (0.19% S, 243 mg/kg B1), high sulphur and normal thiamine (0.63% S, 13.7 mg/kg B1), high sulphur and high thiamine (0.63% S, 243 mg/kg B1). All animals had free access to water and were offered 1 kg/animal/day of diet for 14 weeks, when necropsy was undertaken. Seven lambs fed unsupplemented (normal B1) diets containing added sulphur developed clinical symptoms of polioencephalomalacia (PEM) between the 3rd and 7th week of the trial. Morbidity (P less than 0.013) and mortality (P = 0.08) differences were attributed to S administration. None of the B1 supplemented lambs developed clinical signs of PEM. Body weight and relative organ weights did not differ among treatment groups. Serial sections of all brains were examined grossly and microscopically. Nonparametric statistical analysis revealed sulphur related effects in the cerebrum, midbrain and hindbrain (P less than 0.0001), no thiamine-related effects or interaction between the factors were seen, except in the amygdaloid body. It was concluded that inorganic sulphur was associated with polioencephalomalacia, and that dietary thiamine may decrease the severity of lesions in some affected areas of the central nervous system.

Animal Feed↗

PubMed1977

Some methodological considerations for the clinical evaluation of neuroleptics--comparative effects of clozapine and haloperidol on schizophrenics.

For the purpose of evaluating objectively the characteristics of clinical effects of clozapine and haloperidol, a double-blind comparative trial was conducted on 91 schizophrenic in-patients. The changes of symptoms were assessed by means of several psychiatric and behavioral rating scales. The results were analyzed by means of nonparametric statistical methods. Furthermore, application of multivariate analysis was considered. After 12 weeks of treatment, though no significant difference in general improvement rate was noted between the two groups, a marked different spectrum of clinical effects was observed according to the rating scales. Clozapine is superior in anti-delusional, contact-promoting and sedative anxiolytic effect, while haloperidol is superior in anti-autistic effect. Among the side-effects, extrapyramidal symptoms appeared significatly more severe in the haloperidol group. The frequency of appearance of fever, was significantly greater in the clozapine group than the other. The four dropout cases of the clozapine group were all caused by fever. Through this clinical trial, clinical availability and validity of various statistical analytical methods were reconsidered.

Clozapine↗

PubMed2004

Intra-articular lidocaine plus bupivacaine in sheep undergoing stifle arthrotomy.

OBJECTIVE: To evaluate the effect of intra-articular (i.a.) lidocaine plus bupivacaine on post-operative pain in sheep undergoing stifle arthrotomy. STUDY DESIGN: Randomized controlled experimental trial. ANIMALS: Sixteen adult Rambouillet-cross ewes. METHODS: Sheep were randomly assigned to one of two treatment groups. The lidocaine/bupivacaine group (L/B, n=8) received i.a. lidocaine (40 mg (2 mL)) prior to incision and i.a. bupivacaine (10 mg (2 mL)) post-closure, while the control group (n=8) received no i.a. injections. i.a. local anesthetics were an addition to the standard analgesic protocol of phenylbutazone (1 g orally, every 24 hours for 5 days) and transdermal fentanyl (equivalent to 15 mg), initiated 24 hours prior to surgery. A stifle arthrotomy was performed with the purpose of creating a full-thickness articular cartilage defect. Two observers blinded to treatment assessed sheep for total pain score using a numeric ranking scale that included: comfort, movement, and flock behavior. The first observation (T=0) was obtained the evening of surgery (3-7 hours post-operatively); subsequent observations occurred every 12 hours for 72 hours. Nonparametric statistical tests were used to evaluate differences between groups for total pain score. RESULTS: L/B sheep had significantly lower total pain scores at T=0 than control sheep (p<0.05). No significant differences between treatments were noted at any subsequent time periods. There were no differences attributable to the use of different observers. CONCLUSIONS AND CLINICAL RELEVANCE: i.a. lidocaine plus bupivacaine provided analgesia at 3-7 hours post-operatively. Use of i.a. lidocaine and bupivacaine is a simple, effective, yet inexpensive perioperative analgesic protocol for joint surgery in sheep.

Anesthetics, Local↗

PubMed1986

Sex differences in moral reasoning: response to Walker's (1984) conclusion that there are none.

Data from the Family Socialization and Developmental Competence Project are used to probe Walker's conclusion that there are no sex differences in moral reasoning. Ordinal and nominal nonparametric statistics result in a complex but theoretically meaningful network of relationships among sex, educational level, and Kohlberg stage score level, with the presence and direction of sex differences in stage score level dependent on educational level. The effects on stage score level of educational level and working status are also shown to differ for men and women. Reasons are considered for not accepting Walker's dismissal of studies that use (a) a pre-1983 scoring manual, or (b) fail to control for education. The problems presented to Kohlberg's theory by the significant relationship between educational and stage score levels in the general population are discussed, particularly as these apply to the postconventional level of moral reasoning.

Adult↗

PubMed1988

The treatment of symptomatic benign breast disease with danazol.

A prospective randomized double blind trial, using danazol in a dose of 200 mg twice a day, was carried out on 80 women presenting with severe cyclical symptomatic benign mammary dysplasia. Standardized scores for 4 parameters of disease severity (breast pain, breast tenderness, breast nodularity and breast cysts) were defined and measured monthly on all patients admitted to the trial. Using nonparametric statistical analysis, significant improvement in breast pain, tenderness and nodularity, was found in both the double blind and crossover arms of the trial. An insufficient number of patients presented with breast cysts to draw any conclusions regarding the efficacy of danazol on cysts. Six months of treatment may produce a more sustained response, than 3 months of treatment. Danazol appears to be efficacious in managing patients with severe breast symptoms due to benign disease.

Clinical Trials as Topic↗

PubMedDate not supplied

Seizure frequency and major life events in epilepsy.

A group of 18 patients with chronic epilepsy were followed in an outpatient clinic for 1-6 years. Month-by-month seizure records were kept and the response to treatment was systematically explored. The present study was prompted when three patients became seizure-free, apparently in response to major life events (marriage, parenthood, and retirement) rather than to changes in treatment. All the subjects were interviewed in their own homes with a companion, friend, or relative present. The interview was based on a standard instrument (Life Experiences Survey, LES). The home environment was chosen to facilitate recall of events and to enable subjects to confirm dates. The seizure record was then compared with the parallel life events record. Two methods of analysis were adopted. In the first, each life event was assumed to have impact on seizure frequency only during the month in which it occurred; life event months were compared with non-life-event months. In the second, a life event was considered a watershed; seizure frequencies before and after the event were compared. Nonparametric statistical methods were used. These approaches revealed associations between life events and seizure frequency in three additional patients (total six). Most of the patients who showed an association experienced partial seizures.

Adult↗

PubMed1999

Prospective population-based study of intermittent and continuous convulsive status epilepticus in Richmond, Virginia.

PURPOSE: Previous work suggested that there is a lower mortality for convulsive status epilepticus (SE) with intermittent seizures (intermittent SE) as opposed to SE with continuous seizure activity (continuous SE). A plausible hypothesis to explain this difference is that the shorter ictal time in intermittent SE is responsible for the lower mortality in this group. This study investigates the relative contributions of total ictal time and SE duration to the differing mortalities of intermittent and continuous SE. METHODS: Six hundred forty-five cases of prospectively identified convulsive SE were examined. Nonparametric statistical methods were used to compare continuous SE and intermittent SE variables. Multivariate logistic regression analyses were used to determine which factors were most highly associated with mortality. Intermittent SE cases were analyzed to evaluate the relative contributions of ictal time versus SE duration to mortality. RESULTS: Intermittent SE had a significantly lower mortality than continuous SE (19.6 vs. 31.4%; p < 0.001) in adults but not in children. Intermittent and continuous SE durations did not significantly differ in adult cases but did differ in pediatric cases. Ictal time was significantly shorter than SE duration for intermittent SE in both adults and children. After adjusting for age, etiology, and SE duration, SE type (continuous SE vs. intermittent SE) was shown to have an independent effect on mortality in adults. The relative risk of mortality for continuous SE was 1.79 times that of intermittent SE (p = 0.04). After controlling for SE duration, ictal time did not significantly affect mortality in adults. CONCLUSIONS: Intermittent and continuous convulsive SE were common in both pediatric and adult populations. Intermittent SE had a significantly lower mortality than did continuous SE. This difference in mortality was not completely explained by differences in SE duration, total ictal time, etiology, or age. Further research is needed to identify the factor(s) contributing to the significant difference in mortality between intermittent SE and continuous SE.

Adolescent↗

PubMed2002

Expressing health experience through embodied language.

PURPOSE: To describe embodied language for Japanese elders who suffered a stroke or cardiac disease within the previous year. Embodied language is the overlap of feeling and temporal word use with blood pressure during descriptions of health experience. DESIGN: Exploratory. METHODS: Blood pressure and word use were recorded simultaneously when 17 cardiac and 20 stroke participants described their health experiences for 4 minutes. Blood pressure was measured using a tonometric monitor and word use was measured using linguistic analysis software. Descriptive and nonparametric statistics were used. FINDINGS: Participants with strokes retained higher blood pressure after talking than did cardiac participants. The two groups showed contrasting relationships between word use and blood pressure, particularly for temporal words. CONCLUSIONS: This collaborative research between Japanese and American colleagues was a step toward deciphering shared values, which are important to understanding health for people who have lived through life-changing illness events.

Aged↗

PubMedDate not supplied

Nurses' judgments of pain in term and preterm newborns.

OBJECTIVE: To examine neonatal intensive-care unit nurses' judgments of pain intensity in term and preterm newborns and to describe the cues used to assess the possible presence of pain in newborns. DESIGN: A combination of quantitative and qualitative approaches that included both parametric and nonparametric statistical procedures and a content analysis. SETTING: A large, university-affiliated, tertiary-care hospital in central Canada. PARTICIPANTS: Forty-five registered nurses employed in the neonatal intensive-care unit. INTERVENTIONS: Nurses viewed videotapes of term and preterm newborns and written vignettes. Visual analogue scales and open-ended questions were used. MAIN OUTCOME MEASURES: Pain intensity ratings of full-term and preterm newborns and the cues identified as indicative of pain in newborns. RESULTS: Nurses gave significantly higher pain intensity ratings to the full-term group than to the preterm group of newborns. Some differences were found in the cues identified by the nurses in assessing pain in term versus preterm newborns. CONCLUSIONS: Nurses' judgments of pain intensity in newborns are influenced by the vigor and richness of the newborn's behavior response. Neonatal nurses must be provided with continuing education that focuses upon recognition of the signs and symptoms of pain in newborns.

Adult↗

PubMed1988

Microbial colonization patterns of loosely adherent subgingival plaque in adult periodontitis.

Periodontal plaque is a complex bacterial ecosystem that carries an innate history of colonization, selection and maturation. Detailed examination of this balanced environment can reveal developmental sequences and certain interrelationships, much like an archeological record, that can provide insight in the understanding of plaque formation and maturation. For the present investigation, methods are employed which enable the retrospective elucidation of the historical data of plaque development and the nature of bacterial interactions. Nonparametric statistical methods are used to analyze risk, agreement and interdependence, following analytical techniques which are well established in medical epidemiology, but not generally employed in dentistry. The fundamental concept is that many organisms which are present in plaque prefer or require a pre-existing bacterial miliue for colonization and growth to steady-state level. Plaque samples and Ramfjord attachment level measurements were obtained from 60 adult periodontitis patients. Loosely adherent plaque was sampled and different morphotypes were enumerated by darkfield microscopy. The colonization of small spirochetes (S-SP) within the loosely adherent plaque was essential for the colonization of medium spirochetes (M-SP), odds ratio = 15.7 and filaments (FIL), odds ratio = 22.2. Thus, a temporal colonization sequence is inferred for FIL and M-SP, both requiring S-SP as a prerequisite morphotype. Medium spirochetes, in turn, are required for fusiform (FUS) colonization. M-SP also enhance the colonization of FIL and large motile rods (L-MO-R) within the loosely adherent plaque. These morphotypes were inferred to be sequentially interdependent, each preferring or requiring the presence of the preceding morphotype.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

PubMed2004

Association between nutrition and the prosthetic condition in edentulous elderly.

OBJECTIVES: The aim of this study was to assess the possible risk of malnutrition among the elderly population. SUBJECTS: twenty-three pairs of complete dentures were made for a group of patients and 17 upper complete dentures with implant-supported lower dentures were made for a different group. METHODS: The study was performed at the University of São Paulo--Dental Branch, Brazil. The patients were submitted to a nutritional test, as well as to a clinical examination and interview. Chewing ability and patient's satisfaction with their prostheses were evaluated. The nonparametric statistics proof of chi-squared, level 0.05 was performed and because of the low frequencies. The Fischer test was also used. RESULTS: Patients wearing mandibular implant-supported dentures were considered well nourished (76.47%) when compared with complete dentures users (43.48%). There was a significant difference between the two groups, concerning to chewing ability (chi2 = 5.79) and nutritional status (chi2 = 4.35). CONCLUSION: The risk of malnutrition was higher for elderly wearing complete dentures. The psychological state influences the interest in diet and choice of food.

Aged↗

PubMedDate not supplied

Calibration of the DRASTIC ground water vulnerability mapping method.

Ground water vulnerability maps developed using the DRASTIC method have been produced in many parts of the world. Comparisons of those maps with actual ground water quality data have shown that the DRASTIC method is typically a poor predictor of ground water contamination. This study significantly improved the effectiveness of a modified DRASTIC ground water vulnerability map by calibrating the point rating schemes to actual ground water quality data by using nonparametric statistical techniques and a geographic information system. Calibration was performed by comparing data on nitrite plus nitrate as nitrogen (NO2 + NO3-N) concentrations in ground water to land-use, soils, and depth to first-encountered ground water data. These comparisons showed clear statistical differences between NO2 + NO3-N concentrations and the various categories. Ground water probability point ratings for NO2 + NO3-N contamination were developed from the results of these comparisons, and a probability map was produced. This ground water probability map was then correlated with an independent set of NO2 + NO3-N data to demonstrate its effectiveness in predicting elevated NO2 + NO3-N concentrations in ground water. This correlation demonstrated that the probability map was effective, but a vulnerability map produced with the uncalibrated DRASTIC method in the same area and using the same data layers was not effective. Considerable time and expense have been out-laid to develop ground water vulnerability maps with the DRASTIC method. This study demonstrates a cost-effective method to improve and verify the effectiveness of ground water vulnerability maps.

Calibration↗

PubMed1998

Threshold distributions of phenylthiocarbamide (PTC) in the Chinese population.

The ability to taste phenylthiocarbamide (PTC) is a well-documented Mendelian trait. Mapping and cloning the gene(s) responsible for the PTC tasting ability would help to delineate the molecular basis for the variations in PTC tasting ability in humans and to shed new light on taste chemosensory functions. In view of the spectacular successes in genome science, the positional cloning strategy seems to be a feasible approach to the isolation of the gene(s) underlying the PTC tasting ability. As a first step toward mapping the gene(s), we collected PTC taste threshold data on 106 individuals, most of them being university students, in Shanghai, China. Using various parametric and nonparametric statistical methods, we have found that the data set is best described by a bimodal distribution. The frequency of PTC nontasters is estimated to be 10%. This is consistent with the view that the PTC nontasting ability follows a recessive mode of inheritance. Several authors had previously reported PTC data on Chinese living outside China. Our data are, to our knowledge, the first ever collected from the Chinese population within China.

Adolescent↗

PubMed2005

A clinical study comparing marginal and occlusal accuracy of crowns fabricated from double-arch and complete-arch impressions.

BACKGROUND: The double-arch impression technique is widely used in the provision of laboratory fabricated restorations. However, there is little clinical evidence to support or refute its use. The aim of this prospective clinical study was to evaluate the occlusion and marginal fit of posterior full crowns made from double-arch impressions, and to compare these to control crowns fabricated from conventional complete-arch impressions. METHODS: Ten patients requiring single posterior ceramo-metal full crowns had both double-arch and complete-arch impressions taken of the prepared tooth. Two crowns were fabricated for each tooth, using the casts made from both impression methods. Both crowns were tried in and the occlusion and margins evaluated. The results were composed using nonparametric statistical analysis with the probability level for significance at alpha=0.05. RESULTS: The crowns fabricated from the double-arch impression were found to be more accurate in closure to the intercuspal position and had fewer interferences in lateral excursions. There were no significant differences between the two crown groups regarding protrusive interferences and margin quality. CONCLUSIONS: Crowns fabricated from the double-arch impressions were equivalent in marginal accuracy and superior occlusally to crowns fabricated from the complete-arch impressions.

Crowns↗