Table 2.
Analysis of primary outcomes
| Cooling only | Cooling plus xenon | Geometric mean ratio (95% CI) | Mean difference (95%CI) | ||
|---|---|---|---|---|---|
| Infants with MRI scans | |||||
| Lactate to N-acetyl aspartate ratio | 1·09 (0·90 to 1·32) | .. | |||
| n | 37 | 41 | |||
| Arithmetic mean (SD) | 0·47 (0·94) | 0·68 (1·12) | |||
| Coefficient of variation* | 2·19 | 1·68 | |||
| Geometric mean | 0·34 | 0·47 | |||
| Fractional anisotropy | .. | –0·01 (–0·03 to 0·02) | |||
| n | 35 | 38 | |||
| Mean (SD) | 0·41 (0·01) | 0·40 (0·01) | |||
| Infants with MRI scans surviving to discharge | |||||
| Lactate to N-acetyl aspartate ratio | 0·98 (0·85 to 1·12) | .. | |||
| n | 34 | 33 | |||
| Arithmetic mean (SD) | 0·32 (0·42) | 0·34 [0·77] | |||
| Coefficient of variation* | 1·41 | 1·30 | |||
| Geometric mean | 0·28 | 0·25 | |||
| Fractional anisotropy | .. | –0·01 (–0·01 to 0·01) | |||
| n | 33 | 30 | |||
| Mean (SD) | 0·40 (0·05) | 0·40 (0·05) | |||
Geometric mean ratios were calculated after log (x + 1) transformation. Fractional anisotropy data were extracted from a mask of the posterior limb of the internal capsule via tract-based spatial statistics.
*
Coefficient of variation=√(exp(var)–1), where var is the variance on the log scale.