Complete in MATLAB Beginnings of Antiseptic Surgeries Sir Jo

Complete in MATLAB

Beginnings of Antiseptic Surgeries. Sir Joseph Lister (1827-1912), Professor of Surgery at Glasgow University, influenced by Pasteur\'s ideas, found that a wound wrapped in bandages treated by Carbolic acid (phenol) would often not become infected. Here are Lister\'s data on treating open fractures and amputations: Find and interpret the risk difference, risk ratio, and odds ratio. Find a 95% confidence intervals for the parameters estimated in (a).

Solution

a)suceess=recovered ,fail=death

proportion of patients who can be recovered without carbolic acid=19/34=0.0.5588

proportion of patients who can be recovered with carbolic acid=34/40=0.85

risk difference=0.85-0.5588=0.2912

risk ratio=0.85/0.5588=1.521

so with carbolic acid there is 1.521 times more chance patient is recovered.

odds of patients who can be recovered without carbolic acid=19/15=1.267

odd of patients who can be recovered with carbolic acid=34/6=5.67

odd ratio=5.67/1.267=4.4736

b) The 95% CI is the interval that includes the 95% of risk ratios. Thus, the 95% CI is the interval of values in which the true risk ratio is likely to lie with a probability of 95%

risk ratio=1.37-1.67

risk difference=0.26-0.32

odd ratio=4.02-4.92