Table 3.
Results of the correlation between heart rate variability indices and children’s age.
| r | p | ρ | p | |
|---|---|---|---|---|
| μRR during DAY (ms) | 0.098 | 0.642 | 0.104 | 0.615 |
| σ2RR during DAY (ms2) | − 0.197 | 0.345 | − 0.200 | 0.334 |
| HFRR during DAY (ms2) | − 0.072 | 0.732 | − 0.259 | 0.334 |
| μRR during NIGHT (ms) | − 0.065 | 0.759 | − 0.048 | 0.815 |
| σ2RR during NIGHT (ms2) | − 0.280 | 0.175 | − 0.277 | 0.178 |
| HFRR during NIGHT (ms2) | − 0.219 | 0.293 | − 0.228 | 0.270 |
DAY, daytime; NIGHT, nighttime; μRR, mean of RR; σ2RR, RR variance; HFRR, absolute power in high frequency band of the RR series; r, Pearson product moment correlation coefficient; ρ, Spearman rank correlation coefficient; p, type I error probability.