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Advanced Neurology PSG findings in young poor sleepers

Table 2. Comparing polysomnographic parameters of young adult males with poor sleep quality to normative values of young
healthy adults
Variable Mean SD t p‑value MD 95% CI Cohen’s d
UB LB
TST
Study variable 363.65 33.10 −7.04 <0.001* −40.45 −52.15 −28.75 33.10
Normative value 404.10 45.20
SE
Study variable 89.70 1.55 19.50 <0.001* 5.27 4.72 5.82 1.55
Normative value 84.40 9.30
SOL
Study variable 27.60 6.50 4.75 <0.001* 5.36 3.06 7.66 6.48
Normative value 22.20 13.70
ROL
Study variable 125.90 36.20 3.61 0.001* 22.76 9.93 35.60 36.20
Normative value 103.10 49.90
WK
Study variable 9.73 1.40 −2.72 0.01* −0.67 −1.18 −0.17 1.42
Normative value 10.40 8.70
N1
Study variable 11.80 1.60 18.98 <0.001* 5.32 4.75 5.89 1.60
Normative value 6.50 2.90
N2
Study variable 51.10 2.50 −5.99 <0.001* −2.58 −3.46 −1.70 2.47
Normative value 53.70 8.80
N3
Study variable 12.90 1.80 11.12 <0.001* 3.38 2.76 4.00 1.70
Normative value 9.50 6.60
REM
Study variable 14.00 1.50 −21.53 <0.001* −5.70 −6.24 −5.16 1.50
Normative value 19.70 4.30
Notes: *p<0.05. N1: Non-REM stage 1; N2: Non-REM stage 2; N3: Non-REM stage 3. Normative values were obtained from ref. 16
Abbreviations: CI: Confidence interval; LB: Lower bound; MD: Mean difference; REM: Rapid eye movement; ROL: Rapid eye movement onset latency;
SD: Standard deviation; SE: Sleep efficiency; SOL: Sleep onset latency; TST: Total sleep time; UB: Upper bound; WK: Wakefulness.

difference of +5.36 min, while statistically significant, t = −2.72, p=0.01) with a relatively small mean difference
represents a moderate effect size (Cohen’s d = 0.48). of −0.67%, despite reaching statistical significance. The N1
sleep stage accounted for a significantly larger proportion of
For ROL, participants showed significantly delayed
REM sleep onset compared to normative values (125.90 ± TST in participants compared to normative values (11.80 ±
36.20 min vs. 103.10 ± 49.90 min; t = 3.61, p=0.001). The 1.60% vs. 6.50 ± 2.90%; t = 18.98, p<0.001). This increase of
mean difference of +22.76 min represents a substantial +5.32% indicates a very large effect size (Cohen’s d = 2.18).
delay in REM sleep initiation, with a moderate to large In contrast, the N2 sleep stage was significantly lower in
effect size (Cohen’s d = 0.52). participants compared to normative values (51.10 ± 2.50%
vs. 53.70 ± 8.80%; t = −5.99, p<0.001), with a moderate
3.2.3. Sleep stage architecture mean difference of −2.58% (Cohen’s d = 0.43).
WK after sleep onset was significantly lower in participants The N3 sleep stage was significantly higher in
compared to normative values (9.73 ± 1.40% vs. 10.40 ± 8.70%; participants compared to normative values (12.90 ± 1.80%

Volume 4 Issue 4 (2025) 71 doi: 10.36922/an.8614