Table 2

Exclusionary and confirming HRP cut-off points with polysomnographic AHI cut-off points of ≥5, ≥10 and ≥15

SelectivitySpecificityLR+ (95% CI)Post-test probability+ (95% CI)LR− (95% CI)Post-test probability− (95% CI)HRP+/−, %
To AHI ≥5 from PSG (pretest probability 90%)
≥596572.23 (1.78 to 2.79)95 (94 to 96)0.07 (0.05 to 0.10)39 (31 to 47)90/10
≥1087866,25 (2.73 to 14)98 (96 to 99)0.15 (0.11 to 0.21)57 (50 to 65)80/20
To AHI ≥10 from PSG (pretest probability 82%)
≥597391.59 (1.30 to 1.94)88 (86 to 90)0.08 (0.04 to 0.16)27 (15 to 42)90/10
≥2071907.10 (3.37 to 15)97 (94 to 99)0.32 (0.26 to 0.39)59 (54 to 64)60/40
To AHI ≥15 from PSG (pretest probability 75%)
≥1094602.35 (1.81 to 3.05)88 (84 to 90)0.10 (0.06 to 0.17)23 (15 to 34)80/20
≥2567928.36 (4.09 to 17)96 (92 to 98)0.36 (0.30 to 0.44)52 (47 to 57)52/48
  • AHI, apnoea-hypopnoea index; HRP, home respiratory polygraphy; HRP +/−, %, percentage of patients with a positive/negative diagnosis based on HRP; LR, likelihood ratio; post-test probability +, the post-test probability of obtaining a true positive diagnosis when the test (HRP) was positive; post-test probability −, the post-test probability of obtaining a true positive diagnosis when the test (HRP) was negative.