What is meant by Numbers needed to treat?

a measure that indicates how many patients would require an intervention to reduce the expected number of outcomes by one

How is Numbers needed to treat calculated?

1/(Absolute risk reduction)

What is Experimental event rate (EER)?

(Number who had particular outcome with the intervention) / (Total number who had the intervention)

What is Control event rate (CER)?

(Number who had a particular outcome with the control) / (Total number who had the control)

How do you calculate Absolute risk reduction?

• Experimental event rate - Control event rate
• Control event rate -Experimental event rate

Depending on if the outcome is desirable or not