Wilcoxon Method Research Articles

慢性疾患を有する高齢者の生命予後因子の検討

Clinical assessment and laboratory testing are important in predicting longevity and the outcomes of chronic diseases in the elderly. We therefore studied the prognostic utility of clinical and laboratory findings. A group of 168 elderly patients (70-97 years of age) with chronic diseases who were admitted to Kashiwazaki Kosei Hospital was studied. Data on 13 potentially prognostic factors were analyzed: dementia, being bedridden, anorexia, edema of the lower limbs, urinary incontinence, dyspnea fever, hepatic dysfunction, renal dysfunction, anemia, hypoalbuminemia, inflammation, and electrocardiographic abnormality. Kaplan-Meier survival curves were constructed, and either the log-rank or Wilcoxon method was used to look for significant differences in survival between patients with and without the factors listed above. Regression analysis was then done with the Coxproportional-hazards model to study the factors that contributed to the shortest survival. Patients lived longer if they were not bedridden, anorexic, incontinent of urine, hypoalbuminemic, or if they had no inflammation (p < 0.05): being bedridden, anorexia, urinary incontinence, hepatic dysfunction, hypoalbuminemia, inflammation, and electrocardiographic abnormalities. The survival curve obtained by using these factors as independent variables in the proportional-hazards model was similar to the Kaplan-Meier survival curve.

The Influence of Patient Education Level on the International Prostatic Symptom Score

The American Urological Association developed a questionnaire to quantify the severity of symptoms due to benign prostatic hyperplasia (BPH). An additional question relating to the impact of BPH on the quality of life was added, and this questionnaire became known as the International Prostate Symptom Score (I-PSS) and was adopted by the World Health Organization. The objective of our study was to determine the influence of education on the I-PSS and to analyze the relationship of the effect on the questionnaire when self-administered or administered by professional medical personnel. I-PSS was administered to 92 patients 50 to 81 years old (mean age 63) with BPH. Patients were assessed into 2 groups according to the level of education. Group 1 was composed of 68 patients considered literate and group 2 comprised 24 patients considered illiterate by UNICEF criteria. Patients received orientation about the questionnaire and the manner of completion. The symptom index was self-administered (subgroup P) and administered with physician help (subgroup D). Statistical analysis was done using Wilcoxon method for nonparametric samples and regression analysis. The difference between P and D subgroups in group 1 was not statistically significant (p = 0.55). However, the difference between subgroups P and D in group 2 was statistically significant (p less than 0.001). There was no correlation between the mean I-PSS in subgroup D of literate and illiterate groups. Our study suggests that illiterate patients were not able to answer the questionnaire but with the help of professional medical personnel the I-PSS could be extended to this group of patients without impairing the quality.

The Influence of Patient Education Level on the International Prostatic Symptom Score

The American Urological Association developed a questionnaire to quantify the severity of symptoms due to benign prostatic hyperplasia (BPH). An additional question relating to the impact of BPH on the quality of life was added, and this questionnaire became known as the International Prostate Symptom Score (I-PSS) and was adopted by the World Health Organization. The objective of our study was to determine the influence of education on the I-PSS and to analyze the relationship of the effect on the questionnaire when self-administered or administered by professional medical personnel. I-PSS was administered to 92 patients 50 to 81 years old (mean age 63) with BPH. Patients were assessed into 2 groups according to the level of education. Group 1 was composed of 68 patients considered literate and group 2 comprised 24 patients considered illiterate by UNICEF criteria. Patients received orientation about the questionnaire and the manner of completion. The symptom index was self-administered (subgroup P) and administered with physician help (subgroup D). Statistical analysis was done using Wilcoxon method for nonparametric samples and regression analysis. The difference between P and D subgroups in group 1 was not statistically significant (p = 0.55). However, the difference between subgroups P and D in group 2 was statistically significant (p < 0.001). There was no correlation between the mean I-PSS in subgroup D of literate and illiterate groups. Our study suggests that illiterate patients were not able to answer the questionnaire but with the help of professional medical personnel the I-PSS could be extended to this group of patients without impairing the quality.

Long-term results and risk factors of tumor recurrence in patients with superficial bladder cancer who were treated by intravesical bacillus Calmette-Guerin (BCG) instillation

An evaluation was made of the long-term results and risk factors of tumor recurrence in patients with superficial bladder cancer who were treated with intravesical bacillus Calmette-Guerin (BCG) and who had a mean follow-up period of 57 months. Eligible for the study were a total of 102 patients who were treated by transurethral resection of tumors and were considered to be free from tumor from 1984 to 1989. A suspension containing 80 mg Tokyo 172 strain BCG in 50 ml normal saline was given intravesically to 50 patients once a week for six weeks without further maintenance instillation. To the other 52 patients was additionally given monthly intravesical BCG instillation for 12 months. The actuarial nonrecurrent rates according to sex, different BCG treatment protocol, tumor grade, tumor status including primary or recurrent tumors, and solitary or multiple tumors were estimated by Kaplan-Meier method. The estimated three-, five- and seven-year actuarial nonrecurrent rates in all 102 cases were 77.3%, 68.5% and 60.6%, respectively. When nonrecurrent rates were compared to tumor characteristics, no statistically significant differences were observed between primary and recurrent tumors or between solitary and multiple tumors estimated by generalized Wilcoxon method. On the other hand, when nonrecurrent rates were compared with tumor grades, grade 3 tumor showed a 40.0% three-year nonrecurrent rate. The differences between grade 3 and grade 1 and between grade 3 and grade 2 were statistically significant (p < 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)

The uptake of anticancer drugs by tumor tissues and lymph node and the effectiveness of postoperative adjuvant chemotherapy on survival time

Forty-one patients with advanced gastric cancer underwent gastrectomy and the correlation between tissue uptake of the adjuvant drug and the prognosis were studied. The patients were preoperatively administered Tegafur (Futraful, Taiho Pharmaceutical Co. Ltd, Japan) and samples of tissue were obtained intraoperatively. 5-FU levels in the tumor and lymph nodes were measured by gas chromato-massfragmentography (GCMF). The patients in whom the 5-FU uptake by the tissues was measured and who were given over 60 g of Tegafur as postoperative adjuvant chemotherapy, were divided into two groups; namely, one group in whom the 5-FU uptake by the tumor tissue and lymph nodes was over 0.05 microgram/g and the other in whom the uptake was lower than 0.05 microgram/g. There were no significant differences in the background factors of either group. Each survival rate was calculated by the Kaplan-Meier method, and the generalized Wilcoxon method was used for statistical analysis. There was no statistically significant correlation between the 5-FU uptake by the tumor and the prognosis, however the 5-year survival rate in the group whose 5-FU uptake of the lymph nodes was over 0.05 microgram/g was statistically significant (p = 0.018).

Effect of ibuprofen on doxorubicin toxicity in mice

This study examines the effect of ibuprofen on the toxicity produced in mice by the anticancer drug, doxorubicin. Ibuprofen solution made in 0.02% sodium carbonate, was administered subcutaneously in doses ranging from 10 to 40 mg/kg/day. Sodium carbonate served as a vehicle control and saline was used as a reference control. Treatment with saline, sodium carbonate, or a specific dose of ibuprofen began two days before administration of a single intraperitoneal dose of doxorubicin 17, 20 or 25 mg/kg and then continued for the next thirty days. Mortality was followed for thirty days. The analysis of the data by the Litchfield and Wilcoxon method revealed that there was neither a difference in doxorubicin LD50 values nor in the potency ratios between saline and any dose of ibuprofen treatment. Treatments with sodium carbonate and ibuprofen at 30 mg/kg/day offered slight protection over saline treatment, but it was not statistically significant. All mice, regardless of treatment, receiving doxorubicin showed significant weight loss. It appears that ibuprofen offers little protection against doxorubicin toxicity under these circumstances.

Rank sum multiple comparisons in one- and two-way classifications

The F-test provides a test of the equality of several treatment means. Analogous nonparametric methods are the Kruskal-Wallis (1952) test for the one-way classification and Friedman's X2 or the concordance coefficient of Kendall-Babington Smith for the two-way classification. However, the findings of the F-test or one of its analogues may not be very interesting; we may wish to know why the null hypothesis of equal treatment effects has been rejected. A preliminary narrow characterization of a multiple comparison method might be that it is used to augment the F-test with a view to answering this question. A second line of thought is the following. In scanning the results of an experiment our attention will naturally be drawn to the largest contrasts and the smaller ones will not be examined. We become interested in calculating something very much like a conditional probability: what value will be exceeded by a sample contrast with a prescribed conditional probability, the condition being that the contrast was large enough to attract our attention in the first place from among a class of contrast effects of interest? The various multiple comparison methods are attempts to formulate and answer this imprecise question in different ways and especially for different classes of interesting contrasts. P. Nemenyi, in his unpublished 1963 Princeton University dissertation, 'Distributionfree multiple comparisons', surveys the entire subject of distribution free multiple comparisons. The present work treats two specific distribution free-multiple comparison techniques: (1) the Wilcoxon method and (2) the extreme rank sum test for outliers. The Wilcoxon method of multiple comparisons concentrates on detecting differences between treatment means. In the normal theory case we may ask for the value that will be exceeded by the largest absolute Studentized difference withl given probability. This leads to the Tukey method of multiple comparisons. The Wilcoxon method performs the same practical functions as that of Tukey but with weaker distributional assumptions. The desirability of using sums to detect significant differences in the m-ultiple comparison context was recognized by Kramer (1956). Kramer treated two criteria of classification, whichl we may call objects and judges; the objects are ranked by each of the judges and the sum of these ranks is then determined for each object. Objects with significantly large rank sum differences are then declared to have different means. Wilcoxon clarified the critical 'extreme value' character of this problem and in 1956, in an unpublished notebook, * Present address: Office of Naval Research, Washington, D.C.

Anticonvulsant actions of trimecain and xilocain

Two local anesthetics — xilocain and trimecain (diethylamino-2,4,6-trimethylacetanilide hydrochloride) —employed clinically were tested on mice for their anticonvulsive actions, by applying the maximum electric shock seizure test (MES) and by the corasole induced convulsions test (metrasole test). Their side-effects (neurological toxicity) were studied by the “rotating bar” technique. Both drugs failed to prevent clonic convulsions after administration of 100 mg/kg corasole. Conversely, they abolished the hindlimb tonic extensor phase of the maximum electrical and corasole shock seizures. The ED50 was determined for both drugs, and their relative activity calculated by the Litchfield and Wilcoxon method (1949). Trimecain proved to be only half as potent as xilocain. It is suggested that both drugs have a common anticonvulsant action.

Quantitative measurement of the effect of lysergic acid diethylamide on mice and its interactions with other drugs.

ALTHOUGH several species of animals (including spiders, fighting fish, pigeons and rats) have been used for the quantitative evaluation of the effect of hallucinogenic and psychotomimetic agents it is worth while to add to this list owing to the biochemical differences between species. The present favourite seems to be the rat1. This communication reports a test for the quantitative evaluation of the effect of psychotomimetic agents using mice chosen for their small size (useful if limited quantities of agent—for example, extracts from schizophrenic serum—are available) and ease of handling. A Latin square design was used employing four cages, each of 5 mice, and four modes of injection (saline, lysergic acid diethylamide, drug to be tested, and lysergic acid diethylamide and this drug together). The mice were injected subcutaneously and placed individually on the centre of a vertical pole at 1 min. intervals. The time (up to a maximum of 40 sec.) taken by the mice to reach lines drawn 1 in. from the top or bottom of the pole was then measured. Variability can be reduced by eliminating slow or erratic mice in preliminary tests. (The mice can also be trained to run down the pole under hunger drive. This procedure, however, introduces two new parameters—learning and hunger—which may be differentially affected by drugs.) Doses of lysergic acid diethylamide of 1 and 2 mgm./kgm. were used. The solutions were always freshly prepared and the effect tested of their interaction with adrenochrome, adrenolutin and the brom derivative of lysergic acid diethylamide. Fig. 1 shows the difference between the drug value and its matching saline value, with the latter corrected to a straight line at the level of the first saline value (maximum possible score = 200). All statistical work was done, however, on uncorrected results. As the results obtained were not normally distributed, all statistical evaluations were carried out using non-parametric methods (Wilcoxon's method for paired data).

The chemical evaluation of pyrethrum flowers (Chrysanthemum cinerariaefolium): A comparison of several methods

1. Comparative analyses of pyrethrum flowers have been carried out by the methods of Tattersfield, Seil, Ripert, Haller &amp; Acree and Wilcoxon.2. The methods were of value in indicating the relative richness in pyrethrins of the samples tested, but discrepancies were seen in the absolute values of the pyrethrins I and II recorded. Under present conditions and until a standard method of analysis is agreed upon, it would appear requisite to state the method employed in the evaluation of the flowers.3. The Wilcoxon method has given higher figures for the pyrethrin I content than the Seil method. The degree of divergence between the results depended upon the richness of the flowers, and upon the excess of acid used in distilling the volatile acid in the Seil method. The relationship between the amount of the pyrethrin I acid present and the titration recorded in the Wilcoxon method was not a linear one.4. The question of the solvent to be used for the initial extraction of the flowers has been briefly discussed.