Jalen criteria was developed by Jalen et al to diagnose toxic megacolon in 1969.
What is the historical background of toxic megacolon?
<s>[INST] Answer the question truthfully, you are a medical professional. This is the question: What is the historical background of toxic megacolon? [/INST] \n Jalen criteria was developed by Jalen et al to diagnose toxic megacolon in 1969.</s>