Liniger 2003.

Study characteristics
Methods	Study design: parallel‐group quasi‐randomised trial Study dates: start date: 1992 – end date: 1996 Setting: inpatient procedure – outpatient follow‐up Country: Switzerland
Participants	Inclusion criteria: 27 patients between 36 days to 6 months, with progressive hydrocephalus with documented ventriculomegaly by computed CT scan, MRI or ultrasonographic image scans and requiring a first ventriculoperitoneal CSF shunt insertion Exclusion criteria: not available Sample size: 27 randomised participants Age: Group A: median age at surgery in months 3.4 (1 – 5 months) Group B: median age at surgery in months 2.2 (0 – 4 months) Sex (M/F): not available Relevant participant details: Group A: Congenital/acquired hydrocephalus 8/3 Mean head circumference: 43 cm Percentiles 10 > 97.1 = 97 Ultrasound mean thalamus‐occipital horn distance: 42 mm Mean with of lateral ventricles: 43 Mean (range) of IVP: 185 (100‐240) mm H₂O CT/MRI mean age Evan's index 0.46 (0.3‐0.6) Mean frontal/occipital brain mantle: 15.5/7 mm Group B: Congenital/acquired hydrocephalus 11/3 Mean head circumference: 41 cm Percentiles 10 > 97.1 = 50 Ultrasound mean thalamus‐occipital horn distance: 27 Mean with of lateral ventricles: 47 Mean (range) of IVP: 172 (100‐260) mm H₂O CT/MRI mean age Evan's index 0.32 (0.2‐0.5) Mean frontal/occipital brain mantle: 17/11 mm Previous Surgery: no Details of valve selection: not available
Interventions	Group A (n = 11): “conventional medium pressure valve” (PS Medical flow control valve, Goleta CA, medium pressure) Group B (n = 16): "Anti‐siphon valve" (PS Medical Delta, level 1.0, medium‐low pressure) Common indications: Ventriculoperitoneal shunt was implanted on the right or the side of the larger ventricle.
Outcomes	Treatment failure How measured: defined as the number of patients with revisions and the type of revisions. Shunt revisions were recorded and compared in respect of the valve inserted and in respect of the development of slit ventricles. Time points measured: 3 and 6 months Time points reported: unclear (possibly 6 months) Adverse events How measured: Slit Ventricle (SV) were defined according to the radiological impression of slit‐like or collapsed lateral ventricles in CT or MRI scans. Slit Ventricle syndrome was defined as SV with recurrent clinical signs of intracranial hypertension, namely severe headaches and emesis, and slow or no refill of the valve. Time points measured: at 6 months after shunt insertion (early), and at 6 years of age (late) Time points reported: at 6 months after shunt insertion (early), and at 6 years of age (late) Ventricular size reduction: How measured: width of lateral ventricles (CT scan or MRI) Time points measured: 3 and 6 months Time points reported: unclear (possibly 6 months) Head circumference: How measured: head circumference in cm at a corrected age of 7 years Time points measured: 3 and 6 months Time points reported: unclear (possibly 6 months) Mortality for all causes: not reported Quality of life: not reported
Funding sources	Not available
Declarations of interest	Not available
Notes	Other outcomes included IVP, psychomotor development (unclear scale of measurement), ultrasound imaging, mean Evan's index, mean frontal/occipital brain mantle in mm.
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	High risk	Quote: "infants with progressive hydrocephalus were allocated alternately to either Group A (conventional medium pressure valve) or Group B (Delta valve level 1)". It was not clear that a random sequence was used (quasi‐randomisation).
Allocation concealment (selection bias)	Unclear risk	No information available. See above. Insufficient information to permit judgement of ‘Low risk’ or ‘High risk’
Blinding of participants and personnel (performance bias) Subjective outcomes: treatment failure, adverse events, quality of life	High risk	No information about blinding available, however blinding was unlikely due to the visibly different interventions.
Blinding of participants and personnel (performance bias) Objective outcomes: mortality, head circumference, ventricular size	Low risk	No information about blinding available. Outcomes were likely to be unaffected by blinding.
Blinding of outcome assessment (detection bias) Subjective outcomes: treatment failure, adverse events, quality of life	High risk	No information about blinding available, however blinding was unlikely due to the visibly different interventions.
Blinding of outcome assessment (detection bias) Objective outcomes: mortality, head circumference, ventricular size	Low risk	No information about blinding available. Outcomes were likely to be unaffected by blinding.
Incomplete outcome data (attrition bias) All outcomes	Unclear risk	No information available. Insufficient information to permit judgement of ‘Low risk’ or ‘High risk'
Selective reporting (reporting bias)	High risk	Insufficient information to permit judgement of ‘Low risk’ or ‘High risk’ (no protocol available). However, outcome data were presented at selective time points and frequently not disaggregated by group (e.g. shunt failure defined as elective versus emergency revisions).
Other bias	Low risk	No other sources of bias were detected.