Logistic regression analysis

Specific predictive factors for outcome after surgical intervention have not been well defined in the literature. In one prospective, multicenter observational study of 95 patients, the state of consciousness was the only predictive factor retained in a logistic regression analysis." In this study, there was a 2.8-fold increased risk for poor outcome for each increase on a three-step scale (awake/drowsy, somnolent/ stuporous, and comatose), and good outcomes (modified Rankin Scale score <2) were achieved in 86%, 76%, and 47% of patients within each group, respectively. 

As a part of logistic regression analysis, odds ratio plots are an excellent way to see how much more likely a condition is to exist based on the presence of another condition. Just by glancing at an odds ratio plot, you can see whether an independent variable is significant to the dependent variable. For instance, if the odds ratio confidence interval does not cross the value of 1, then the independent variable odds ratio is significant. Examine the following graph. 

This classification of bonds allowed the application of logistic regression analysis (LoRA), which proved of particular benefit for arriving at a function quantifying chemical reactivity. In this method, the binary classification (breakable or non-breakable, represented by 1/0, respectively) is taken as an initial probability P0, which is modelled by the following functional dependence (Eqs. 7 and 8) where f is a linear function, and x. are the parameters considered to be relevant to the problem. The coefficients c. are determined to maximize the fit of the calculated probability of breaking (P) as closely as possible to the initial classification (P0). 

One method that we have found particularly useful for our purposes is logistic regression analysis (LoRA). In this method, a binary classification is taken as a probability, Pq (given the value 0 or 1) and modelled by the two coupled equations 5 and 6. 

Increased compared with chamber controls (0 ppm),/> < 0.05, based on logistic regression analysis... 

Multiple logistic regression analysis A statistical model used to predict the probability of the occurrence of an event using several predictor variables. 

Table 9 Multivariate logistic regression analysis predictors of restenosis of ORAR II randomized...

Patients with good adherence to therapy have a higher incidence of adverse effects (12). Logistic regression analysis identified four factors that discriminate adherent (n = 48) from non-adherent (n = 30) patients the course of the illness, the employment status of a key relative, age at onset of the illness, and the presence or absence of adverse effects. 

A randomized comparison of oral atenolol and bisoprolol in 334 patients with acute myocardial infarction was associated with drug withdrawal in 70 patients (21%) because of significant bradydysrhythmias, hypotension, heart failure, and abnormal atrioventricular conduction (40). Logistic regression analysis suggested that critical events were more likely to occur in patients who were pretreated with dihydropyridine calcium antagonists. 

A retrospective analysis of postoperative renal function in patients undergoing cardiac operations has been conducted to evaluate whether the use of prophylactic intravenous diltiazem, in order to reduce the incidence of ischemia and dysrhythmias, was associated with increased renal dysfunction (10). The incidence of acute renal insufficiency requiring dialysis was 4.4% with diltiazem versus 0.7% in the controls. Logistic regression analysis suggested that the risk of acute renal insufficiency was strongly associated with intravenous diltiazem, age, baseline serum creatinine, the presence of left main coronary disease, and the presence of cerebrovascular disease. 

Wada T, Ueda M, Abe K, Kobari T, Yamazaki H, Nakata J, Ikemoto I, Ohishi Y, Aizawa Y. [Risk factor of hver disorders caused by flutamide—statistical analysis using multivariate logistic regression analysis.] Hinyokika Kiyo 1999 45(8) 521-6. 

If removal is not expertly handled in problematic cases, considerable scarring can result, and some users have proceeded to litigation as a consequence of such complications. Complications in the removal of Norplant capsules have been evaluated in 3416 cases from 11 countries (48). Complications were reported in 4.5% of removals, usually attributable to implants being broken during removal (1.7%) or being embedded below the subdermal plane (1.2%). Logistic regression analysis showed that the most important risk factors for complicated removals were complications at insertion and an infection at the implant site (before or at the time or removal). For women without complications, the mean removal time was 12 minutes, but for those with complications the mean increased to 30 minutes. These results illustrate the necessity of proper insertion technique, under aseptic conditions. Capsules become surrounded by a fibrous sheath within 3 months after implantation beyond a few months, there is no difference in complication rate by duration of use. 

In a retrospective analysis of 2774 women who had had one prior cesarean delivery, there was a 1% incidence of uterine rupture in women who were given oxytocin, compared with 0.4% in non-augmented controls with spontaneous labor (12). Six women needed emergency hysterectomy. The odds ratio for uterine rupture in the oxytocin-treated women was 4.6 by logistic regression analysis (Cl = 1.5,14). The small number of events limited the study it had only 30% power to detect changes of that magnitude. However, it is reasonable to proceed cautiously, with... 

---