A study reports a standardised mortality ratio of 120 for a local hospital. How should this be interpreted?
Answer and explanation
Correct answer: D. Observed deaths are 20 percent above those expected
- Step 1: SMR is observed deaths divided by expected deaths, multiplied by 100.
- Step 2: A value of 100 means as expected, so 120 is 20 percent higher.
Answer
Observed deaths are 20 percent above those expected.
Why not the others: Twenty percent of patients died: It is not the proportion who died. Deaths are 20 percent lower than expected: Over 100 means excess, not fewer. Deaths are 120 times the national average: It is not 120 times.
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