摘要:

This article is designed to help investigators in applying to qualitatively classified clinical and laboratory data the appropriate statistical treatment—tests of significance in binomial and multinomial distributions, estimation of confidence limits, analysis of contingency tables, and estimation of sample sizes required for further investigation. Section A is a brief introduction (definitions and principles). Section B comprises 40 examples classified so that the investigator can choose data and problems comparable to his own. Questions that arise in the examples, regarding experimental design (especially random sampling) and the interpretation of the tests, are discussed in Section C (Notes).Because the standard deviation of the binomial and the chi square contingency test are often used without appreciation of the risk entailed, tables, which can be used also in nonmedical investigation, are presented: binomial confidence limits (with graphs) and exact probabilities for small-sample fourfold contingency tables. For samples not covered by the tables, precautions and rules regarding the use of chi square have been derived from more than five hundred comparisons between chi square and the exact method. To help in the exact computation of probabilities where that is necessary, four-decimal logarithms of factorials of numbers up to 1000 are given.

ISSN:1923-4287    

DOI:10.1139/cjr48e-001

出版商:NRC Research Press    

年代:1948

数据来源: NRC

摘要:

A series of dogs poisoned by exposure to phosgene gas were treated by tracheotomy and suction applied by insertion of a catheter deep into the trachea. By this method of treatment, animals were brought out of a moribund condition and the survival time was definitely increased. The survival rate, however, was essentially the same as that of the control animals. Although digitalis augments the heart beat, clears up irregularities, and keeps the heart beating for a time after respiration has failed, it may be detrimental by increasing the effusion of the fluid into the lung rather than decreasing it. The higher the pregassing concentration of haemoglobin the smaller the amount of fluid that effused into the lungs and the greater was the chance of survival. In practically all animals the point at which haemoconcentration reached a maximum was between 22 and 23 gm. of haemoglobin per 100 mils of blood. On post-mortem examination of dogs dying from phosgene poisoning the stomach was found to be markedly distended with gas and the vessels congested. This adds to the embarrassment of respiration and circulation. The big problem in the treatment of phosgene poisoning is still the finding of some substance or means of limiting or preventing the effusion of fluid into the airways of the lung.

ISSN:1923-4287    

DOI:10.1139/cjr48e-002

出版商:NRC Research Press    

年代:1948

数据来源: NRC

摘要:

not available

ISSN:1923-4287    

DOI:10.1139/cjr48e-003

出版商:NRC Research Press    

年代:1948

数据来源: NRC