Table 3

Change scores and comparisons between participants randomised to usual care or CPAP

Baseline mean (SD)Final mean (SD)Average within group change scores (95% CIs)Between allocated group differences
CPAPUsual careCPAPUsual careCPAPUsual careMean (95% CI)P values
PASAT* 99.17
(45.26)
99.69
(46.28)
117.66
(45.71)
116.92
(47.17)
18.19
(12.67 to 23.71)
15.91
(8.40 to 23.41)
2.29
(−7.09 to 11.66)
0.63
KSS†4.86
(2.32)
4.24
(2.03)
3.51
(1.82)
4.14
(2.02)
−1.36
(−1.99 to  −0.72)
−0.09
(−0.79 to 0.61)
−1.26
(−2.20, to −0.32)
0.01
RAVLT immediate recall* 6.45
(2.27)
6.12
(1.93)
7.49
(2.22)
7.03
(2.50)
1.04
(0.49 to 1.59)
0.91
(0.49 to 1.33)
0.13
(−0.55 to 0.81)
0.70
RAVLT total recall* 47.62
(12.27)
46.95
(11.30)
50.53
(11.56)
49.93
(12.51)
2.92
(0.68 to 5.16)
2.99
(0.97 to 5.00)
−0.07
(−3.05 to 2.91)
0.96
RAVLT learning* 5.00
(1.89)
5.41
(2.05)
4.15
(2.34)
4.53
(2.31)
−0.85
(−1.53 to −0.17)
− 0.88
(−1.50 to 0.26)
0.03
(−0.88 to 0.94)
0.94
RAVLT short term memory* 9.51
(3.35)
9.45
(3.83)
9.99
(3.13)
10.38
(3.55)
0.51
(−0.22 to 1.25)
0.99
(0.32 to 1.65)
−0.47
(−1.45 to 0.51)
0.34
RAVLT delayed recall* 8.77
(3.87)
8.97
(4.00)
9.68
(3.70)
10.09
(3.58)
0.94
(0.27 to 1.62)
1.08
(0.40 to 1.76)
−0.14
(−1.09 to 0.81)
0.77
RAVLT forgetting†2.69
(2.45)
2.53
(2.43)
1.96
(2.14)
1.47
(2.20)
−0.75
(−1.40 to  −0.10)
−1.05
(−1.64 to –0.47)
0.30
(−0.56 to 1.17)
0.49
RAVLT recognition* 12.70
(2.43)
13.51
(1.51)
13.55
(1.64)
13.63
(1.63)
0.73
(0.20 to 1.27)
0.12
(−0.30 to 0.54)
0.61
(−0.06 to 1.29)
0.07
SDMT* 42.21
(11.04)
42.19
(14.10)
46.14
(11.74)
43.62
(15.10)
3.73
(1.52 to 5.93)
1.43
(−0.94 to 3.81)
2.30
(−0.93 to 5.52)
0.16
Digit Span forwards* 9.78
(2.17)
9.32
(2.35)
10.14
(2.27)
9.53
(2.43)
0.36
(−0.16 to 0.87)
0.21
(−0.23 to 0.65)
0.15
(−0.52 to 0.81)
0.67
Digit Span backwards* 8.05
(2.05)
7.91
(2.18)
8.55
(2.68)
8.13
(2.58)
0.49
(0.02 to 0.97)
0.22
(−0.27 to 0.71)
0.27
(−0.41 to 0.95)
0.43
HADS anxiety†5.57
(3.96)
5.25
(3.84)
4.42
(3.42)
4.95
(3.25)
−1.10
(−1.92 to  −0.28)
−0.30
(−1.11 to 0.50)
−0.79
(−1.93 to 0.34)
0.17
HADS depression†6.28
(3.78)
5.72
(4.07)
5.16
(3.42)
5.22
(3.80)
−1.06
(−1.75 to −0.36)
−0.65
(−1.61 to 0.31)
−0.40
(−1.58 to 0.78)
0.50
POMS tension/anxiety†9.21
(7.00)
8.22
(6.01)
8.16
(6.42)
6.45
(5.49)
−1.04
(−2.38 to 0.30)
−1.81
(−2.95 to –0.67)
0.77
(−0.97 to 2.51)
0.38
POMS depression†11.90
(10.40)
11.68
(10.94)
9.84
(10.53)
8.81
(10.11)
−2.07
(−4.27 to 0.13)
−2.96
(−5.19 to –0.73)
0.89
(−2.21 to 4.00)
0.57
POMS anger†7.59
(6.28)
7.15
(6.14)
8.53
(7.31)
6.61
(5.50)
0.95
(−0.48 to 2.37)
−0.61
(−1.91 to 0.69)
1.55
(−0.36 to 3.47)
0.11
POMS vigour* 16.11
(6.46)
16.76
(6.17)
16.96
(6.64)
17.77
(5.60)
0.85
(−0.70 to 2.40)
1.14
(−0.34 to 2.61)
−0.29
(−2.41 to 1.84)
0.79
POMS fatigue†10.75
(6.30)
10.57
(6.03)
9.66
(5.93)
9.00
(5.82)
−1.10
(−2.37 to 0.17)
−1.64
(−3.01 to –0.26)
0.54
(−1.32 to 2.40)
0.57
POMS confusion†9.08
(5.30)
7.62
(4.26)
7.92
(5.20)
7.27
(3.99)
−1.16
(−2.45 to 0.13)
−0.42
(−1.29 to 0.45)
−0.75
(−2.29 to 0.80)
0.34
POMS total†32.42
(32.81)
28.47
(31.38)
27.15
(35.67)
20.37
(29.17)
−5.27
(−12.22 to 1.67)
−8.57
(−14.93 to –2.21)
3.29
(−6.04 to 12.63)
0.49
AQoL illness* 0.15
(0.20)
0.16
(0.21)
0.36
(0.30)
0.35
(0.29)
0.20
(0.13 to 0.27)
0.18
(0.13 to 0.24)
0.02
(−0.07 to 0.11)
0.65
AQoL relationships* 0.70
(0.26)
0.71
(0.25)
0.76
(0.17)
0.76
(0.18)
0.06
(−0.003 to 0.12)
0.04
(−0.02 to 0.11)
0.01
(−0.07 to 0.10)
0.74
AQoL sensory* 0.95
(0.07)
0.94
(0.10)
0.95
(0.08)
0.93
(0.09)
−0.01
(−0.03 to 0.01)
−0.001
(−0.02 to 0.01)
−0.01
(−0.03 to 0.02)
0.51
AQoL mental health* 0.81
(0.16)
0.81
(0.17)
0.83
(0.14)
0.84
(0.12)
0.02
(−0.02 to 0.07)
0.03
(−0.01 to 0.07)
−0.01
(−0.06 to 0.05)
0.83
AQoL total health utility* 0.14
(0.14)
0.15
(0.16)
0.29
(0.23)
0.27
(0.19)
0.15
(0.09 to 0.20)
0.11
(0.08 to 0.15)
0.03
(−0.03 to 0.10)
0.32
BNSQ†42.31
(11.18)
42.07
(11.28)
36.71
(10.66)
38.82
(11.58)
−6.44
(−9.27 to 3.62)
−3.58
(−6.42 to –0.74)
2.86
(−1.11 to 6.84)
0.16
  • Bold indicates significant within-group improvement from baseline. P values refer to between-group comparisons of change scores.

  • *Higher test scores represent better functioning.

  • †Lower test scores represent better functioning.

  • AQoL, Assessment of Quality of Life; BNSQ, Basic Nordic Sleep Questionnaire; Digit Span, Digit Span subtest of the Wechsler Adult Intelligence Scale IV; HADS , Hospital Anxiety and Depression Scale; KSS, Karolinska Sleepiness Scale; PASAT, Paced Auditory Serial Addition Task; KSS, Karolinska Sleepiness Scale; POMS, Profile of Mood States; RAVLT, Rey Auditory Verbal Learning Test; SDMT, Symbol Digit Modalities Test.