Table 3

Likelihood ratios (95% CI) of individual patterns of cerebral blood flow abnormality for pairwise disease group comparisons (significant results are underlined and the direction of change in odds indicated)

Pattern of CBF abn
(a)Alzheimer’s disease vVascular dementiaLewy body diseaseFrontotemporal dementiaProgressive aphasia
Bilateral posterior 4.6 (1.9–11.2)1.8 (0.7–4.5) 4.3 (1.6–11.4)
Bilateral posterior plus unilateral anterior 3.9 (1.2–12.8) 0.4 (0.2–0.8)∞(↑)
Unilateral posterior0.9 (0.3–2.4)4.0 (0.5–30.5) 0.2 (0.1–0.5)
Bilateral anterior 0.1 (0.0–0.46) 0.1 (0.0–0.2) 0.1 (0.0–0.4)
Bilateral anterior plus unilateral posterior 0.2 (0.0–0.7) 0.1 (0.0–0.6) 0.1 (0.0–0.4)
Unilateral anterior0.4 (0.1–2.3)0.3 (0.1–1.7)0.3 (0.0–3.5)
Unilateral anterior plus unilateral posterior0.4 (0.1–1.3)0.6 (0.1–2.0)0.4 (0.1–2.0)
Generalised1.5 (0.8–3.0)1.0 (0.4–2.2)1.9 (0.8–4.4)4.3 (0.6–30.0)
Patchy 0.4 (0.2–0.8)0.6 (0.2–1.8)0.8 (0.3–1.7)1.2 (0.3–4.8)
No abnormality2.4 (0.7–8.1)1.1 (0.3–4.6)1.3 (0.4–3.9)∞(↑)
(b) Vascular dementia v Alzheimer’s disease Lewy body disease Frontotemporal dementia Progressive aphasia
Bilateral posterior 0.2 (0.5–0.1)0.4 (0.1–1.3)0.9 (0.3–3.3)
Bilateral posterior plus unilateral anterior 0.3 (0.8–0.1) 0.1 (0.0–0.4)
Unilateral posterior1.1 (3.1–0.4)4.5 (0.6–36.1) 0.2 (0.1–0.7)
Bilateral anterior 7.3 (24.9–2.2) 0.5 (0.3–0.8)0.7 (0.3–1.8)
Bilateral anterior plus unilateral posterior 6.8 (31.1–1.5)0.9 (0.3–2.2)0.6 (0.2–1.7)
Unilateral anterior2.5 (14.9–0.4)0.7 (0.2–3.6)0.9 (0.1–7.7)
Unilateral anterior plus unilateral posterior2.4 (7.2–0.8)1.3 (0.4–4.2)1.0 (0.2–4.4)
Generalised0.7 (1.3–0.3)0.6 (0.2–1.6)1.2 (0.5–3.2)2.8 (0.4–20.9)
Patchy 2.4 (4.5–1.3)1.5 (0.6–4.1)1.9 (0.9–3.9)2.8 (0.7–11.2)
No abnormality0.4 (1.5–0.1)0.5 (0.1–2.6)0.6 (0.1–2.4)
(c) Lewy body disease v Alzheimer’s disease Vascular dementia Frontotemporal dementia Progressive aphasia
Bilateral posterior 0.6 (1.4–0.2)2.6 (8.9–0.8)2.4 (0.7–8.9)0
Bilateral posterior plus unilateral anterior 2.5 (4.8–1.3) 9.8 (33.2–2.9) (↑) (↑)
Unilateral posterior000 0
Bilateral anterior0000(↓)
Bilateral anterior plus unilateral posterior0000
Unilateral anterior0000
Unilateral anterior plusunilateral posterior0000
Generalised1.1 (2.5–0.5)1.6 (4.3–0.6)2.0 (0.7–6.0)4.6 (0.6–36.2)
Patchy1.6 (4.4–0.6)0.7 (1.7–0.3)1.2 (0.4–3.6)1.8 (0.4–9.0)
No abnormality0.9 (3.8–0.2)2.2 (12.2–0.4)1.2 (0.2–6.2)
(d)Frontotemporal dementia v Alzheimer’s disease Vascular dementia Lewy body disease Progressive aphasia
Bilateral posterior 0.2 (0.6–0.1)↓1.1 (3.8–0.3)0.4 (1.5–0.1)
Bilateral posterior plus 0(↓)0 0(↓)0
Unilateral posterior0.3 (2.0–0.0)0.2 (1.8–0.0) 0.1 (0.0–0.4)
Bilateral anterior 15.9 (51.3–5.0) 2.2 (4.0–1.2) (↑)1.6 (0.7–3.7)
Bilateral anterior plus unilateral posterior 8.0 (37.2–1.7)1.2 (3.1–0.5)0.7 (0.2–2.1)
Unilateral anterior3.4 (19.9–0.6)1.3 (6.4–0.3)1.1 (0.1–10.4)
Unilateral anterior plus unilateral posterior1.8 (6.5–0.5)0.8 (2.1–0.2)0.8 (0.2–3.9)
Generalised0.5 (1.2–0.2)0.8 (2.1–0.3)0.5 (1.5–0.2)2.3 (0.3–17.9)
Patchy1.3 (2.9–0.6)0.5 (1.1–0.3)0.8 (2.5–0.3)1.5 (0.4–6.6)
No abnormality0.8 (2.3–0.3)1.8 (7.7–0.4)0.8 (4.2–0.2)
(e)Progressive aphasia v Alzheimer’s disease Vascular dementia Lewy body disease Frontotemporal dementia
Bilateral posterior 0000
Bilateral posterior plus unilateral anterior00 0(↓)0
Unilateral posterior 4.7 (11.2–1.9) 4.1 (11.1–1.6) (↑) 18.5 (141.5–2.4)
Bilateral anterior 10.0 (38.9–2.6)1.4 (3.4–0.6)0.6 (1.5–0.3)
Bilateral anterior plus unilateral posterior 12.0 (61.6–2.3)1.8 (5.3–0.6)1.5 (4.7–0.5)
Unilateral anterior3.0 (31.7–0.3)1.2 (10.8–0.1)0.9 (8.0–0.1)
Unilateral anterior plus unilateral posterior2.4 (11.6–0.5)1.0 (4.5–0.2)1.3 (6.7–0.3)
Generalised0.2 (1.6–0.0)0.4 (2.6–0.1)0.2 (1.7–0.0)0.4 (3.5–0.1)
Patchy0.9 (3.5–0.2)0.4 (1.4–0.1)0.6 (2.7–0.1)0.7 (2.9–0.2)
No abnormality0000
  • ↑Significant increase in likelihood ratio for target disease; ↓Significant decrease in likelihood ratio for target disease; (↑ )/(↓)significant increase/decrease in likelihood ratio for target disease if frequency is set to one for those disease group comparisons for which the actual frequency of a particular test result is zero (see statistical methods); ∞=infinity (denominator is zero); CBF abn = cerebral blood flow abnormality.