Table 3 |
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Range, interquartile range and standard deviation of haemoglobin measurements from 48 intensive care patients listed in Table 1 |
|
| Measure |
Calculation |
| Range |
The values in this dataset range from 5.4 to 14.1 g/dl |
| Interquartile range |
The median calculated in Table 2 splits the data into two equally sized groups. The lower and upper quartiles split
the data into four equally sized groups (4 × 12) and are therefore most easily defined
as the average of the 12th and 13th observations for the lower quartile and of the
36th and 37th observations for the upper quartile. In other words, the lower and upper
quartiles are 8.7 and 10.8 g/dl, respectively. (There are more complicated methods
for calculating the interquartile range [1], but these will not generally give markedly different results.) |
| Standard deviation (SD) |
Using the formula given above: |
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Whitley and Ball Critical Care 2002 6:66 doi:10.1186/cc1455 |
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