Table 6.

Cognitive interview results: responses

Response scale	Debriefing characteristic
	Interpreted as intended, n (%)	Response scale matches question, n (%)
1. 0 (No skin itching)–10 (very severe skin itching)	15/15 (100.0)	11/11 (100.0)
2. 0 (No skin redness)–10 (very severe skin redness)	15/15 (100.0)	10/10 (100.0)
3. 0 (No skin pain)–10 (very severe skin pain)	12/14 (85.7)	11/12 (91.7)
4. 0 (No skin burning)–10 (very severe skin burning)	13/15 (86.7)	4/5 (80.0)
5. 0 (No skin scaling)–10 (very severe skin scaling)	15/15 (100.0)	8/9 (88.9)
6. 0 (No skin stinging)–10 (very severe skin stinging)a	14/14 (100.0)	8/8 (100.0)
7. 0 (No skin cracking)–10 (very severe skin cracking)	14/15 (93.3)	11/11 (100.0)
8. 0 (No skin flaking)–10 (very severe skin flaking)a	15/15 (100.0)	11/11 (100.0)
9. 0 (No skin dryness)–10 (very severe skin dryness)	14/15 (93.3)	11/11 (100.0)
10. 0 (No skin irritation)–10 (very severe skin irritation)	12/15 (80.0)	7/8 (87.5)
11. 0 (No skin sensitivity)–10 (very severe skin sensitivity)	14/14 (100.0)	8/8 (100.0)
12. 0 (No skin lesions)–10 (very severe skin lesions)	15/15 (100.0)	10/11 (90.9)
13. 0 (No skin thickening)–10 (very severe thickening)	15/15 (100.0)	9/10 (90.0)
14. 0 (No itch-related sleep loss)–10 (worst possible itch-related sleep loss)a	14/15 (93.3)	11/11 (100.0)
15. 0 (No fatigue)–10 (worst possible fatigue)	11/13 (84.6)	7/8 (87.5)
16. 0 (No feelings of embarrassment)–10 (worst possible feelings of embarrassment)	15/15 (100.0)	13/13 (100.0)
17. 0 (No avoidance of my usual activities)–10 (completely avoided doing my usual activities)a	15/15 (100.0)	12/12 (100.0)
18. 0 (No impact on personal relationships)–10 (completely impacted personal relationships)a	15/15 (100.0)	13/13 (100.0)
19. 0 (No impact on my choice of clothing)–10 (completely impacted my choice of clothing)	15/15 (100.0)	10/10 (100.0)

P-SIM psoriasis symptoms and impacts measure

^aThis item was ultimately removed from the final 14-item P-SIM