In the early part of this century, the drug company, Merck, produced a powerful non- steroidal anti-inflammatory drug (NSAID) known as Vioxx. Vioxx was very effective in reducing pain due to arthritis and, unlike some NSAIDs, did not cause digestive system or liver problems. However, a couple of years after Vioxx was introduced to the market, some independent studies showed a possible connection between NSAIDs and increased risk of heart attack in the elderly. Since many arthritis sufferers (and many Vioxx users) are elderly, these studies were a cause of concern. To test whether this was the case for Vioxx, Merck conducted a large-scale study in which 3025 randomly selected elderly Vioxx users were put on the drug while 2875 were given a placebo. The volunteers were monitored for 18 months. During this time, 334 of the Vioxx group members and 272 members of the placebo group suffered heart attacks.

Required:
a. Compute by hand a 90% confidence interval for the difference in heart attack risk between Vioxx users and non-Vioxx users (the placebo group.)
b. Interpret the interval. What action does it suggest should be taken regarding Vioxx?

a

b

The  interval means that there is 90% confidence that the true difference between the proportion of Vioxx users who suffered from heart attack  and the non-Vioxx users (the placebo group  ) who suffered from heart attack  lie within the interval

The  use of Vioxx drug should be stopped

Step-by-step explanation:

From the question we are told that

   The sample size for Vioxx users is  

   The second sample size for placebo is  

   The number of Vioxx users that suffered heart attack is  

     The number of non-Vioxx users that suffered heart attack is  

    Generally the  sample proportion for Vioxx users is mathematically represented as

=>  

=>  

    Generally the  sample proportion for placebo users is mathematically represented as

=>  

=>    

Generally the confidence level is 90% , then the level of significance is  

=>  

Generally the critical value of   from the normal distribution table  is  

Generally the standard error is mathematically represented as

=>  

=>  

Generally the margin of error is mathematically represented as

=>    

=>    

Generally the 90%  confidence interval is mathematically represented as

=>      

The  interval means that there is 90% confidence that the true difference between the proportion of Vioxx users who suffered from heart attack  and the non-Vioxx users (the placebo group  )  lie within the interval

Looking at the interval we see that proportion of Vioxx users who suffered is  more compared to  non-Vioxx users (the placebo group  )[i.e the both limit of the interval is  positive ] hence the  use of Vioxx drug should be stopped

33

step-by-step explanation: g=6

answer: 177/8

step-by-step explanation: