Table 4 Summary of issues and solutions during the cognitive interviews
Issue | Category | Solutions |
|---|---|---|
Round 1 PRO | ||
Interpretations of “eye discomfort” were highly variable across patients | Inconsistency in interpretation | Item retained without modification for further testing in round 2 |
There was disagreement on whether pain and discomfort represented the same concept or should be assessed separately | Inconsistency in interpretation | Item retained without modification for further testing in round 2 |
Itching commonly reported in concept elicitation | Relevance | Item on itching added for testing in round 2 |
Round 2 PRO | ||
Foreign body sensation and discharge were commonly reported in concept elicitation | Relevance | Items on foreign body sensation and discharge added for testing in round 3 |
Participants provided various recall periods when answering questions. There was also variability in symptom severity over the course of the day | Clarity in recall period | 24-h recall period added for testing in round 3; participants were asked to recall symptoms/signs at their worst over a 24-h period |
Round 3 PRO | ||
Discharge commonly reported in concept elicitation | Relevance | Item on discharge added for testing in round 3, but on completion of this round, discharge was removed from the final PRO to focus on symptoms only |
Interpretations of “eye discomfort” were highly variable across patients | Inconsistency in interpretation | Item removed from the final PRO |
Round 1 ObsRO | ||
None | – | – |
Round 2 ObsRO | ||
As there was variability in symptom severity over the course of the day, a 24-h recall was recommended | Clarity in recall period | 24-h recall period added for testing in round 3; participants were asked to recall symptoms/signs over 24-h period |
Round 3 ObsRO | ||
None | – | – |