This is done by setting the appropriate thresholds you are looking for on the measures you are using for the Business Transaction. Rajanikanth posted a very helpful link: https://answers.dynatrace.com/spaces/148/uem-open-q-a_2/questions/181740/how-to-configure-incident-r...
Follow the screenshots in the link provided and you should be able to set up exactly what you're looking at here.
Yes, I used the information that James provided. I am also wildcarding on a parameter so I that is where I am not sure it will work the way I 1-create-the-bt-split.jpg2-create-web-request-measure.jpg3-create-bus-transaction-with-split-and-measure.jpg4-incident-based-on-response-time-but-change-to-co.jpgwant. I will upload my steps.