Predictions of the Length of Lumbar Puncture Needles

Table 4

The coefficient of determination () of different models and their corresponding success rate.

	Predictor		Success rate, %
L4-L5	Weight	0.37	49.2
	BMI	0.43	50.0
	Weight/height	0.43	51.6
	Weight/height + gender	0.46	54.4
L3-L4	Weight	0.44	56.5
	BMI	0.48	56.8
	Weight/height	0.51	59.2
	Weight/height + gender	0.52	59.2
Men
L4-L5	Weight	0.47	52.1
	BMI	0.49	54.2
	Weight/height	0.51	55.2
L3-L4	Weight	0.52	58.3
	BMI	0.54	63.5
	Weight/height	0.55	60.4
Women
L4-L5	Weight	0.43	47.7
	BMI	0.37	44.9
	Weight/height	0.42	47.2
L3-L4	Weight	0.47	58.5
	BMI	0.42	49.4
	Weight/height	0.47	56.3

Success rate: percent of the predicted cerebrospinal fluid location between the minimal and maximal depths.