Table 3.

Incidence of HIZ on lumbar MR images in various body weight groups (n = 637)

Body weight (kg)	HIZ			Total
	Present	Absent	Incidence rate (%)
< 50	2	29	6.45	31
50–59.5	20	71	21.98	91
60–69.5	70	137	33.82	207
70–79.5	61	122	33.33	183
80–89.5	37	59	38.54	96
> = 90	11	18	37.93	29

χ² = 16.384, P = 0.006