Table 4.

Cognitive Interview Results for the Symptom Checklist of the ACSD

Item on Initial Version (First 13 interviews)	Item on Revised Version (Last 17 interviews)	Selected Quotations Demonstrating Patients’ Interpretations of Each Item
Cough	Cough	Have I had a cough in the past 24 hours.
Shortness of breath or difficulty breathing at rest or with activity	Shortness of breath or difficulty breathing	Initial version of the ACSD: It just means is it hard to breathe when you’re sitting or lying, or you’re walking or moving around, do you have a hard time taking a breath. Initial version: I definitely think my responses would have been different if you had separate “at rest” versus “with activity,” but “shortness of breath” versus “difficulty breathing” I don't think would have changed it at all. Revised version: It’s asking if I have had any issues with my breathing.
Feeling feverish	Feeling feverish	Like I know personally when I have a fever, I always have like burning in my eyes or chills, or like my face is really flushed, so when I read feeling feverish, I think about the symptoms I have when I have a fever.
Chills	Chills	Like when you just feel like you’re freezing for no reason, shaky and cold.
Fatigue (low energy)	Fatigue (low energy)	Not having the energy to do what I would normally do, being at home, like housework, that kind of thing.
Body pain or muscle pain or aches	Body pain or muscle pain or aches	Did you have any aches or pains.
Diarrhea	Diarrhea	If I’m having some diarrhea, soft stool, uncontrolled stool, something like that.
Nausea	Nausea	If you feel like you’ve got to throw up.
Vomiting	Vomiting1	Have I actually thrown up anything from my stomach.
Headache	Headache	Have you had any pain in your head in the past 24 hours.
Sore throat	Sore throat	Have I experienced any sore throat or irritation of the throat in the last 24 hours.
Nasal obstruction or congestion (stuffy nose)	Nasal obstruction or congestion (stuffy nose)	If I’m congested, stuffy.
Nasal discharge (runny nose)	Nasal discharge (runny nose)	Have you experienced any runny nose in the last 24 hours.
I have a loss of taste	Loss of taste1	I would say that would mean either you can’t taste the food at all or you don't have your normal sense of taste.
I have a loss of smell	Loss of smell1	Have I had loss of smell in the past 24 hours.

¹Four changes to the ACSD are recommended for future research: dropping the item assessing vomiting, adding items assessing brain fog and dizziness, and using 4-point response scales (i.e., absent, mild, moderate, severe) for loss of taste and smell rather than dichotomous responses (i.e., yes, no)