Results
Of the 400 subjects in this study, 40(10%) had a weak or absent LCR when tested with the RCT. When asked to produce a voluntary cough, 81 of the 400 subjects (20.3%) had an abnormal (weak or absent) voluntary cough (Table 1). The binary principal end point for the study was the development of pneumonia (Table 2). An appropriate test of the significance for this situation is the X² test, with the null hypothesis that there is no difference between patients who were administered the RCT and patients who were not administered the RCT. A significant difference was found (P>0.001). There were no adverse side effects or complications from administering the RCT.
Five of the 400 patients administered the RCT developed pneumonia. They were treated with oral antibiotics and recovered. None of the 5 required transfer from the rehabilitation facility. Of the 400 patients who received the RCT, 20 received percutaneous endoscopic gastrostomy placement. Of these, 7 were removed before discharge. The 204 patients at the sister facility did not receive the RCT, and 27 of these patients developed pneumonia. Three of the 27 patients died of pneumonia in the rehabilitation hospital, and 7 were transferred to the emergency department and intensive care setting.
In addition to a test of significance, it is of interest to determine a 95% CI for p1-p2, where p1 is the proportion of patients who developed pneumonia after the RCT was administered and p2 is the proportion of patients who developed pneumonia without being administered the RCT. An appropriate CI is the CI for independent samples. The 95% CI for p1-p2 is -0.167 to – 0.072, with a 95% confidence level.
The odds in favor of not developing pneumonia among the patients who were administered the RCT were compared with the odds in favor of not developing pneumonia among the patients who were not administered the RCT. The odds ratio test indicated that the odds in favor of not developing pneumonia for those patients who did not receive the RCT were significantly smaller than the odds in favor of not developing pneumonia for those patients who received the RCT. In fact, the ratio of the odds is 0.08, which is significantly <1, and the 95% CI for the odds ratio is 0.031 to 0.219 (Table 3).