Table 4.
Comparison of time-domain features among BNP level groups
| Feature types | Time-domain features | Group 1 (n = 249) | Group 2 (n = 85) | Group 3 (n = 85) | χ2 | P value |
|---|---|---|---|---|---|---|
| Duration feature | t5 | 0.413 (0.341,0.489) | 0.443 (0.376, 0.509) | 0.391 (0.317, 0.470)∆∆ | 9.245 | 0.010 |
| T | 0.761 (0.680, 0.843) | 0.796 (0.726, 0.857) | 0.717 (0.643, 0.846)∆∆ | 9.460 | 0.009 | |
| Proportional feature | h4/h1 | 0.478 (0.412, 0.530) | 0.468 (0.412, 0.518) | 0.419 (0.380, 0.503)** | 10.651 | 0.005 |
| t1/T | 0.190 (0.169, 0.214) | 0.183 (0.164, 0.205) | 0.200 (0.175, 0.223)∆ | 7.859 | 0.020 | |
| w1 | 0.191 (0.170, 0.213) | 0.196 (0.165, 0.222) | 0.183 (0.135, 0.209)* | 8.600 | 0.014 | |
| w2 | 0.143 (0.122, 0.165) | 0.148 (0.115, 0.172) | 0.130 (0.100, 0.161)∆ | 8.337 | 0.015 | |
| w1/T | 0.255 (0.229, 0.279) | 0.250 (0.217, 0.275) | 0.240 (0.209, 0.266)** | 10.522 | 0.005 | |
| w2/T | 0.189 (0.167, 0.214) | 0.185 (0.159, 0.213) | 0.175 (0.149, 0.199)* | 6.787 | 0.034 |
Data shown are M (Q1, Q3)
*compared with Group 1, P < 0.05; **compared with Group 1, P < 0.01; ∆compared with Group 2, P < 0.05; ∆∆compared with Group 2, P < 0.01