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. 2008 Sep 18;8:80. doi: 10.1186/1471-244X-8-80

Table 2.

Comparison of clinical symptom scales and sleep parameters before and after CBT, n = 28.

Pre-treatment Post-treatment Significance
Insomnia Severity Index [ISI] 17.68 (s.d. 4.49) 10.89 (s.d. 5.40) p < 0.001a
Epworth Sleepiness Scale [ESS] 11.75 (s.d. 5.25) 8.64 (s.d. 5.07) p = 0.03a
Beck Depression Inventory [BDI] 7.0 (IQR 2.0–10.0)* 2.0 (IQR 0–6.0)* p < 0.001b
Beck Anxiety Inventory [BAI] 10.07 (s.d. 6.41) 5.39 (s.d. 4.43) p = 0.002a
Hamilton Rating Scale for Depression [HAMD] 6.5 (IQR 3.0–10.5)* 1.0 (IQR 0–1.5)* p < 0.001b
modified Clinical Global Impression [mCGI]
(mCGI-Severity for pre-treatment and mCGI-Impression for post-treatment conditions)
9.0 (IQR 8.0–10.0)* 4.0 (IQR 2.0–4.5)* p < 0.001b
Total sleep time TST [min] 361.80 (s.d.113.20) 454.12 (s.d.59.37) p = 0.01a
Sleep latency SL [min] 26.0 (IQR 11.98–46.10)* 7.25 (IQR 3.83–13.0)* p = 0.004b
Sleep efficiency SE [%] 77.58 (s.d. 19.28) 89.60 (s.d. 8.43) p = 0.004a
Wake after sleep onset WASO [min] 80.42 (s.d. 56.85) 48.27 (s.d. 37.17) p = 0.02a
Stage 1 [min] 28.5 (IQR 22.0–41.75)* 22.75 (IQR 16.5–37.0)* p = 0.29b
Stage 2 [min] 154.48 (s.d. 51.43) 149.12 (s.d. 55.72) p = 0.72a
Stage 3+4 [min] 112.52 (s.d. 80.62) 175.09 (s.d. 94.09) p = 0.01a
REM [min] 65.59 (s.d. 43.49) 107.91 (s.d. 49.12) p = 0.001a

In most cases data are expressed as the mean (standard deviation). Characters in bold indicate significance (p < 0.05).

* Data are presented as median (interquartile range) due to non-normal data distribution

a – Paired-Samples T test; b – Wilcoxon Sign Rank Test;

IQR – interquartile range; s.d. – standard deviation; N.S. – non significant