Table 3.
Univariate and multivariate mixed effects logistic regression analysis investigating seizure features associated with seizure detection.
| Threshold 0.4: logistic regression analysis |
Threshold 0.5: logistic regression analysis |
Threshold 0.6: logistic regression analysis |
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|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Univariate analysis | Multivariate analysis | Univariate analysis | Multivariate analysis | Univariate analysis | Multivariate analysis | |||||||||||||
| Outcome: seizure detected | OR | (95% CI) | p-value | OR | (95% CI) | p-value | OR | (95% CI) | p-value | OR | (95% CI) | p-value | OR | (95% CI) | p-value | OR | (95% CI) | p-value |
| Peak amplitude | 1.04 | (1.03–1.05) | <0.001 | 1.02 | (1.01–1.04) | <0.001 | 1.03 | (1.03–1.04) | <0.001 | 1.02 | (1.01–1.03) | <0.001 | 1.02 | (1.01–1.02) | <0.001 | 1.01 | (1.01–1.02) | <0.001 |
| Number of channels-seizure onset | 1.55 | (1.28–1.88) | <0.001 | 1.6 | (1.31–1.94) | <0.001 | 1.43 | (1.19–1.71) | <0.001 | |||||||||
| Number of channels-seizure peak | 1.76 | (1.46–2.13) | <0.001 | 1.46 | (1.14–1.86) | 0.002 | 1.79 | (1.50–2.13) | <0.001 | 1.46 | (1.15–1.86) | 0.002 | 1.68 | (1.43–1.98) | <0.001 | 1.35 | (1.07–1.70) | 0.011 |
| Rhymicity | <0.001 | 0.004 | <0.001 | <0.001 | <0.001 | 0.015 | ||||||||||||
| Significant dysrhythmia | 1 | 1 | 1 | 1 | 1 | 1 | ||||||||||||
| Minimal dysrhythmia | 2.9 | (1.57–5.38) | 2.49 | (1.08–5.75) | 2.92 | (1.58–5.38) | 1.54 | (0.69–3.45) | 2.92 | (1.49–5.72) | 1.43 | (0.58–3.56) | ||||||
| Highly rhythmic | 14.87 | (7.07–31.25) | 4.96 | (1.93–12.78) | 10.2 | (5.21–19.98) | 4.43 | (1.91–10.24) | 8.2 | (4.13–16.26) | 3.03 | (1.21–7.60) | ||||||
| Seizure morphology-onset | 0.329 | 0.176 | 0.501 | |||||||||||||||
| RDD | 1 | 1 | 1 | |||||||||||||||
| RDT | 2.46 | (0.68–8.84) | 1.96 | (0.78–4.93) | 1.87 | (0.78–4.48) | ||||||||||||
| RDA | 3.64 | (0.36–36.39) | 3.8 | (0.81–17.88) | 2.74 | (0.32–23.14) | ||||||||||||
| SH | 0.67 | (0.30–1.49) | 0.81 | (0.49–1.35) | 0.8 | (0.41–1.57) | ||||||||||||
| SH + W or SP + W | 0.88 | (0.49–1.58) | 1.09 | (0.68–1.74) | 1.2 | (0.70–2.03) | ||||||||||||
| Seizure morphology-peak | <0.001 | <0.001 | <0.001 | |||||||||||||||
| RDD | 1 | 1 | 1 | |||||||||||||||
| RDT | 7.46 | (0.66–84.06) | 1.21 | (0.18–8.36) | 1.33 | (0.18–9.63) | ||||||||||||
| SH | 1.85 | (0.70–4.84) | 2.51 | (0.94–6.67) | 3.33 | (1.14–9.72) | ||||||||||||
| SH + W or SP + W | 5.38 | (2.45–11.78) | 5.43 | (2.46–12.02) | 7.68 | (3.20–18.46) | ||||||||||||
| Change in morphology-start to peak | <0.001 | <0.001 | 0.012 | <0.001 | 0.035 | |||||||||||||
| No | 1 | 1 | 1 | 1 | 1 | |||||||||||||
| Yes | 3.23 | (2.01–5.19) | 2.75 | (1.79–4.24) | 2.33 | (1.21–4.48) | 2.31 | (1.50–3.56) | 2.02 | (1.05–3.88) | ||||||||
| Frequency variability | 19.46 | (8.35–45.33) | <0.001 | 3.58 | (1.32–9.66) | 0.012 | 3.65 | (2.05–6.48) | <0.001 | 2.54 | (1.64–3.93) | <0.001 | ||||||
| EEG background | 0.873 | 0.946 | 0.656 | |||||||||||||||
| Normal | 1 | 1 | 1 | |||||||||||||||
| Mildly abnormal | 0.85 | (0.45–1.60) | 0.93 | (0.52–1.64) | 1.32 | (0.72–2.41) | ||||||||||||
| Severely abnormal | 0.98 | (0.25–3.82) | 1.06 | (0.39–2.91) | 1.28 | (0.41–3.98) | ||||||||||||
| Seizure duration (secs) | 1.02 | (1.02–1.03) | <0.001 | 1.02 | (1.01–1.03) | <0.001 | 1.02 | (1.02–1.03) | <0.001 | 1.02 | (1.01–1.02) | <0.001 | 1.02 | (1.02–1.03) | <0.001 | 1.02 | (1.01–1.02) | <0.001 |
(1) Features with p > 0.05 in the univariate analysis were excluded from the multivariate analysis. (2) The multivariate model was selected using backward stepwise deletion. (3) The variable “Number of channels at seizure onset” was not included in the multivariate model due–colinearity with the feature “Number of channels at seizure peak”.