Question

the aim of a study was to determine how symptom recognition and perception influence clinical presentation as a function of a race. researchers characterized symptoms and care seeking behaviour in african-america patients with chest pain seen in the emergency department. one of the presenting vital signs was systolic blood pressure (SBP). among 157 African-American patients, the mean SBP was146 mmHg with a standard deviation of 27. Existing research on SBP in African-Americans suggests that SBP is not normally distributed. assume that alpha=0.05 and determine whether on the basis of these data you can conclude that the mean SBP for a population of African-American men is greater than 140mmHg.

Answer 1

H_0^: = 140

H₁: > 140

The test statistic z = ()/(s/)

= (146 - 140)/(27/sqrt(157))

= 2.78

At alpha = 0.05, the critical value is z_0.05 = 1.645

Since the test statistic value is greater than the critical value (2.78 > 1.645), so we should reject the null hypothesis.

So at 0.05 significance level, we can conclude that the mean SBP for A population of African-American men is greater than 140 mmHg.