SRDR 5.6. Risk of Bias

The Risk of Bias tab is where you will build out questions that catalogue the various threats to validity a study may have based on study design and execution (i.e., how the authors carried out the study).

The information you capture on this tab are absolutely critical for evaluating the trustworthiness of the study’s findings. For background on what risk of bias is and why it is important for systematic reviews, see the Brown University Evidence Synthesis Academy’s course module: Assessing Risk of Bias.

How to Set Up the Risk of Bias Tab

The Risk of Bias tab is structured a bit differently than the other tabs in SRDR+. While you can, of course, set up your own questions, we don’t recommend this. There are risk of bias tools that are commonly used and which already have research to support their validity. Given this, SRDR+ makes it easy for you to pull in pre-made risk of bias tools into your project.

When you click on the Add questions from a pre-defined list, the following dialogue box will open.

First, select the study design that best fits the studies included in your systematic review. When you do, the list will expand and you can see the list of pre-built risk of bias tools available to add to your project.

And that’s pretty much all there is to it when setting up the Risk of Bias tab in SRDR+

What If My Systematic Review Includes Studies with Different Designs?

For some projects you may need to include studies with different sorts of designs. Let’s say we were carrying out a systematic review that included both clinical trials and cohort studies. In this case, I’d need two different risk of bias tools.

Happily, you can add multiple risk of bias tools to your Risk of Bias tab. This could be confusing for data extractors since they may not know exactly which questions apply to which designs. But, you can get around this problem by including a screening question at the top of the Risk of Bias tab and then using the Dependencies function to turn on only the questions that apply to that particular design. It’s a little bit of work setting it up, but remember, you didn’t have to build out all the risk of bias questions by hand, so it’s not terrible.

In the example below, we included both the Cochrane ROB tool questions at the top and the Newcastle-Ottowa Tool for Cohort studies at the bottom (which you can’t see in the example below, but trust us, they are there). By selecting one of the options in the screener questions, the data extractor will then “turn on” only the questions that apply to that design.