Question

10 PPH4801/MPHDHM9 Jan/Feb 2016 QUESTION 2 A clinical tral is run to assess the efficacy of a new drug to reduce high blood pressure Patents with a diagnosis of hypertension are recruted to participate in the tnal and randomised to receive ether the new drug or placebo Particpants take the assigned drug for 12 weeks and their blood pressure status is recorded At the end of the tral, participants are classified as stil having hypertension or not The data are shown below Hypertension status by treatment Group Number fr hypertension at 12 weeks 50 50 100 Placebo New drug Total 14 20 What is the prevalence of hypertension at the start of the tial (expressed as a percentage)? 21 22 What is the prevalence of hypertension at the end of the tnal (expressed as a5 percentage)? Estimate the relative nsk companng the proportions of patients who are free of hypertension at 12 weeks between groups Please offer an explanation or interpretation of your result 23 (15) [25]

Answer 1

Ans 2

2.1)The prevalence of hypertension at the start of the trail is 50% for placebo and 50% for new drug users out of100 diagnosed hypertensive cases

2.2)The prevalence of hypertension at the end of the trail is

In placebo 6 are free of hypertension (it means 44 are still hypertensive)

To convert this in percentage 44÷50×100=88%

In new drug 14 are free of hypertension (it means 36 are still hypertensive)

To convert this in percentage 36÷50×100=72%

In a total 20 are not hypertensive out of 100 (remaining 80are hypertensive)

So the total percentage of cases with hypertension is 80÷100×100=80%

At the end of the trail 80% of them ate still hypertensive

2.3)The relative risk rate on comparison shows that 88% chance when on placebo and 72% chance on new drug usage.