Make your assessment: Randomizing Participants

How did you do? For reference, here’s a chart of the sequence generation methods that have a “low risk of bias” and those with a “high risk of bias.”

Low risk of bias

High risk of bias

Random number generator Date of Birth
Random number table Date or day of admission
Coin tossing Hospital or clinic record number
Shuffling cards or envelopes Clinician judgement
Throwing dice Participant preference
Drawing lots

When you’re assessing a study’s sequence generation method (for possible selection bias), check to see if the method used falls in the “low risk of bias” or “high risk of bias” column. If the method isn’t described, or if you’re unsure, you should label this domain as “unclear.”

Before we move on to the next domain, there’s one last thing to keep in mind…