Table 3.

Number of shunt responders/non-responders depending on results of lumbar puncture or ICP monitoring

	Lumbar puncture				ICP monitoring*
	CSFP wave amplitude during opening phase		CSF wave amplitude during lumbar infusion		ICP wave amplitude
	< 2 mmHg	≥ 2 mmHg	< 4 mmHg	≥ 4 mmHg	< 4 mmHg	≥ 4 mmHg
Responder (n = 35)	13	22	4	31	1	34
Non-Responder (n = 10)	8	2	6	4	7	3
Statistics	Sensitivity = 63; Specificity = 80 PPV = 92; NPV = 38		Sensitivity = 88; Specificity = 60 PPV = 89; NPV = 60		Sensitivity = 97; Specificity = 70 PPV = 92; NPV = 88

* Mean ICP wave amplitude from the period 11 p.m. to 7 a.m. PPV = Positive predictive value; NPV = Negative predictive value.