Table 2.
Values for HR, LF, HF, and LF/HF during Four Periods in KC and IC Conditions1
| KC (n = 13) | IC (n = 10) | Comparison KC vs. IC 3 | |||||
|---|---|---|---|---|---|---|---|
| M | SD | M | SD | Z | df | p-value | |
| HR (beats/min) | |||||||
| BL | 146.46 | 9.36 | 152.07 | 12.83 | 2.20 | 1 (19) | < .05 |
| HW | 152.10 | 11.65 | 153.71 | 11.91 | 0.11 | 1 (18) | > .05 |
| HS | 158.64 | 13.58 | 164.87 | 14.48 | 2.43 | 1 (16) | < .05 |
| RC | 146.42 | 14.17 | 153.86 | 14.12 | 1.44 | 1 (18) | > .05 |
| Comparison across 4 periods 2 | F (3, 12) = 4.43, p < .05 | F (3, 9) = 12.16, p < .001 | |||||
| LF (ms2) | |||||||
| BL | 6.30 | 10.38 | 2.83 | 2.65 | 2.59 | 1 (19) | < .01 |
| HW | 19.44 | 54.37 | 6.84 | 6.38 | 0.60 | 1 (18) | > .05 |
| HS | 30.05 | 41.26 | 17.62 | 24.55 | 3.43 | 1 (17) | < .001 |
| RC | 15.16 | 29.85 | 3.13 | 2.46 | 1.46 | 1 (18) | > .05 |
| Comparison across 4 periods 2 | F (3, 10) = 4.06, p < .05 | F (3, 9) = 4.75, p < .01 | |||||
| HF (ms2) | |||||||
| BL | 2.05 | 3.77 | 1.38 | 3.10 | 2.00 | 1 (19) | < .05 |
| HW | 22.91 | 70.57 | 5.96 | 8.62 | 1.12 | 1 (18) | > .05 |
| HS | 48.50 | 71.04 | 23.52 | 35.96 | 1.24 | 1 (17) | > .05 |
| RC | 19.89 | 54.42 | 0.50 | 0.52 | 1.71 | 1 (18) | > .05 |
| Comparison across 4 periods 2 | F (3, 10) = 6.18, p < .01 | F (3, 9) = 10 .88, p < .001 | |||||
| LF/HF ratio | |||||||
| BL | 6.32 | 4.56 | 11.18 | 9.00 | 0.77 | 1 (20) | > .05 |
| HW | 5.12 | 5.71 | 4.23 | 4.90 | 0.95 | 1 (18) | > .05 |
| HS | 3.89 | 6.69 | 1.75 | 1.84 | 0.07 | 1 (17) | > .05 |
| RC | 7.61 | 5.26 | 10.60 | 8.63 | 3.59 | 1 (18) | < .001 |
| Comparison across 4 periods 2 | F (3, 10) = 6.07, p < .01 | F (3, 9) = 11.63, p < .001 | |||||
1
HR = arithmetic mean, LF, HF, L/HF = geometric means;
2
Comparison across 4 periods: Repeated measures analysis of variance was used;
3
Comparison KC vs. IC: Generalized Estimating Equations model was used; KC = Kangaroo Care condition; IC = Incubator care condition; BL = Baseline; HW = Heel Warming; HS = Heel Stick; RC = Recovery; LF = low frequency power; HF = high frequency power; LF/HF = Low/High frequency power ratio.
This study was supported by AWHONN to the first author and National Institute of Nursing Research, NIH (RO3NR08587-01) to the third author.