Table 5 Summary of cognitive debriefing findings

Conceptual relevance

• All items deemed relevant by patients

• Most key symptom/side effect and impact concepts assessed, although some are missing (e.g. neuropathic symptoms, excessive mucus production)

• “I: Is there anything important you feel that’s missing from either of the questionnaires? 01–06-M-57: No.”

• “You could probably ask about there wasn’t anything really on here about nerves, neuropathy, whether your feet or hands or fingers are still normal or tingly, numb, anything like that, because I think that must happen quite a bit with chemo…” (01–04-M-59)

Interpretation and understanding

• Instructions well understood and consistently followed

• Items generally well understood and interpreted consistently; problematic items included those assessing a ‘long’ or ‘short’ walk, and “sticky saliva”; mainly associated with the definitions of what these consisted of

• “They are asking me to do a response to the questions by circling the number that applies best to my condition and my situation.” (01–05-M-57)

• “That I just think it’s confusing... I would say a distance or even a timeframe…maybe you can say a 20-min walk or a one mile walk.” (01–10-M-35)

Response scale and options

• Largely considered appropriate

• Patients with feeding tubes at the time of study completion had difficulty responding to items related to eating and swallowing

• “I: The response options; do you think they’re suitable? The four response options? 01–14-F-61: Yes.”

• “I: That’s quite an important point you’ve brought up there, obviously some of these are not relevant to you. Do you feel that there should be an answer that says ‘not relevant’? Yes.” (01–12-M-70)

Recall period

• Recall employed for Items 1–5 varied, due to no specified recall period

• The recall period of the remaining items was easily understood but not always adhered to throughout

• “I: Again, the recall period, what recall period were you thinking of? 01–15-F-32: Right now these are last week as well.”

• “The only comment I made at the beginning, being clear about the timeframe one through five, and once you get past one through five you understand. But I think that would be… you could go through the first five questions and answer them with the wrong timeframe.” (01–03-M-55)