Question

A certain drug can be used to reduce the acid produced by the body and heal damage to the esophagus due to acid reflux. The manufacturer of the drug claims that more than 94​% of patients taking the drug are healed within 8 weeks. In clinical​ trials, 226 of 236 patients suffering from acid reflux disease were healed after 8 weeks. Test the​ manufacturer's claim at the a=0.05 level of significance.

Answer 1

Solution :

Null Hypothesis

Alternative Hypothesis (Claim ) (Right tailed test )

Total number of patients , n = 236

Number of patients suffering from acid reflux disease were healed after 8 weeks are , X = 226

Therefore, the proportion of patients suffering from acid reflux disease were healed after 8 weeks is , p = X/n = 226/236 = 0.9576

Test Statistic :

Since alternative hypothesis is right tailed we will apply right tailed test for testing significance of Z. The significant value of Z at 5% level of significance for right tailed test is 1.645

Since computed value of Z = 1.344 is less than 1.645, it is not significant and we accept the null hypothesis at 5% level of significance.

Conclusion : There is not sufficient evidence to support the manufacturer's claim that more than 94​% of patients taking the drug are healed within 8 weeks.