Advanced: Troubleshooting Variables

My variable is computing dates or time periods incorrectly

Brim includes an option for including today's date in the LLM prompt.

• If computing your variable requires knowledge of today's today, scroll down to the bottom of the Edit/Create variable form, and make sure the box next to "Include Today's Date in Prompt" is checked.
• Specify the format you want a time period in explicitly (number of hours, number of minutes, number of days) and whether you want the variable to round up or down.

My variable is pulling a lot of irrelevant evidence

The LLM tries to find relevant evidence, and without more information, it can find too much.

• Try explaining the difference between what you want included and excluded. You can do this in the Variable Instructions, or by labelling examples in Label Review and Optimizing the variable.
• Be as black and white as you can in the instruction. Try adding the instruction to "Ignore" the specific case(s) you want to exclude

I'm not getting any results when I generate

By default, Brim hides label instances that represent an "Empty" response. In Label Review > Variables > choose a variable, try clicking "Show Default value labels".

If "Show Default value labels" is on and you see values now:

• Verify that your data set has evidence for this variable.
• Try making the variable name more descriptive.

If "Show Default value labels" is on and you still don't see values:

• Verify that your data set is loaded
• In the Variable Settings, scroll down, click "Advanced Settings" and ensure that:
  • The "Include variable in generation" box is checked.
  • The "Restrict variable to specific documents" option is empty or includes correctly spelled document names you want to look through.
• Ensure that the patient you're looking at was included in your most recent label generation.
• Try generating again for this specific patient.

The LLM Reasoning for my variable is drawing the wrong conclusion

Vague or faulty LLM reasoning is often a consequence of the LLM not knowing how to behave in a specific situation:

• Explicitly tell it how to react if it is missing relevant information (e.g. "If there are no values for the input variable, return False.")
• Check that the variable is receiving the information it needs from the notes.