Table 3 Frequency for each of the symptoms of the Cox and Swinson (2002) depersonalisation/derealisation inventory (2002) and median score for items scored >0. *p<0.05.

Depersonalisation/derealisation symptoms	Healthy subjects				Vestibular patients
	(n = 121)		(n = 50)		(n = 50)
	Frequency	If positive, score range (median)	Frequency	If positive, score range (median)	Frequency	If positive, score range (median)
1. Surroundings seem strange and unreal	17%	1–2 (1)	8%	1–2 (1)	40%*	1–4 (2)
2. Time seems to pass very slowly	36%	1–2 (1)	18%	1–2 (1)	24%	1–4 (2)
3. Body feels strange or different in some way	15%	1–2 (1)	10%	1–1 (1)	50%*	1–4 (2)
4. Feel like you've been here before (déjà vu)	65%	1–4 (1)	56%	1–3 (1)	32%*	1–2 (2)
5. Feel as though in a dream	22%	1–3 (1)	10%	1–2 (1)	46%*	1–4 (1)
6. Body feels numb	9%	1–2 (1)	6%	1–1 (1)	26%*	1–3 (1)
7. Feeling of detachment or separation from surroundings	18%	1–2 (1)	14%	1–2 (1)	40%*	1–4 (2)
8. Numbing of emotions	20%	1–3 (1)	10%	1–1 (1)	24%	1–4 (2)
9. People and objects seem far away	10%	1–3 (1)	2%	1–1 (1)	24%*	1–4 (2)
10. Feeling detached or separated from body	7%	1–2 (1)	6%	1–2 (1)	30%*	1–3 (2)
11. Thoughts seem blurred	27%	1–2 (1)	20%	1–2 (1)	46%*	1–3 (2)
12. Events seem to happen in slow motion	13%	1–2 (1)	4%	1–1 (1)	26%*	1–3 (1)
13. Your emotions seem disconnected from yourself	14%	1–2 (1)	6%	1–1 (1)	30%*	1–3 (2)
14. Feeling of not being in control of self	15%	1–3 (1)	10%	1–1 (1)	50%*	1–3 (2)
15. People appear strange or unreal	12%	1–2 (1)	4%	1–1 (1)	22%*	1–3 (2)
16. Dizziness	21%	1–2 (1)	8%	1–1 (1)	88%*	1–4 (3)
17. Surroundings appear covered with a haze	9%	1–1 (1)	10%	1–1 (1)	30%*	1–4 (2)
18. Vision is dulled	7%	1–1 (1)	6%	1–1 (1)	40%*	1–3 (2)
19. Feel as if walking on shifting ground	6%	1–2 (1)	4%	1–1 (1)	64%*	1–4 (2)
20. Difficulty understanding what others say to you	21%	1–3 (1)	12%	1–2 (1)	40%*	1–3 (2)
21. Difficulty focusing attention	36%	1–3 (1)	18%	1–2 (1)	60%*	1–4 (2)
22. Feel as though in a trance	13%	1–2 (1)	6%	1–1 (1)	32%*	1–4 (2)
23. The distinction between close and distant is blurred	3%	1–2 (1)	2%	2–2 (2)	24%*	1–3 (2)
24. Difficulty concentrating	49%	1–3 (1)	30%	1–2 (1)	60%*	1–4 (2)
25. Feel as though your personality is different	15%	1–2 (1)	8%	1–1 (1)	22%	1–4 (2)
26. Feel confused or bewildered	19%	1–3 (1)	8%	1–1 (1)	36%*	1–4 (2)
27. Feel isolated from the world	11%	1–2 (1)	8%	1–2 (2)	26%*	1–3 (2)
28. Feel “spacey” or “spaced out”	22%	1–2 (1)	4%	1–1 (1)	48%*	1–4 (2)