Garcia 1988.

Study characteristics
Methods	Study design: parallel‐group randomised trial Study dates: study dates not available Setting: inpatient procedure ‐ outpatient follow‐up Country: Mexico
Participants	Inclusion criteria: adult patients with hydrocephalus Exclusion criteria: not available Sample size: 84 patients Age (years): Group 1 (intervention) mean 43.1 Group 2 (control) mean 43.7 Sex (M/F): Group 1 57% male; 43% female Group 2 56% male; 44% female Relevant participant details (diagnosis): Neoplasm (8.6% intervention, 15.7% control) ‐ including meningeoma, medulloblastoma and pineal tumours Inflammatory (60.8% intervention, 42.1% control) ‐ including cysticercosis and nonspecific arachnoiditis Vascular (13% intervention, 15.7% control) ‐ including subarachnoid haemorrhage and cerebellar infarction or haemorrhage Other (17.3% intervention, 26.3% control) ‐ including traumatic, congenital and normotensive
Interventions	Group 1 (n = 46): Biomed distal valve (antireflux). This group received 54 valves. Seven patients received more than one valve (15 systems due to dilatation or failure). Group 2 (n = 38): Cordis‐Hakim proximal valve (ball in cone). This group received 42 valves. Eight patients received more than one valve (23 systems due to dilatation or failure). Co‐interventions: all patients received antibiotic prophylaxis (doxycycline and chloramphenicol) and a computerised tomography before the surgery, at the 7th and 15th and 30th day postoperatively.
Outcomes	Treatment failure How measured: surgical re intervention for changing the shunting device due to obstruction, infection, or over‐drainage G1: 9 valves in 8 patients (14%) G2: 17 valves in 11 patients (46%) Time points measured: G1: 12.7 ± 4.6 months G2: 9.4 ± 7.3 months. Time points reported: G1: 1 to 21 months. G2: 1 to 36 months Subgroups: none Adverse events How measured: CSF culture (infection) or computerised tomography scan ‐ > also reported under treatment failure. Time points measured: "early" or "late" (mean follow‐up 4 months, range 1‐24 months) Time points reported: idem Subgroups: none Mortality How measured: not specified Time points measured: complete follow‐up (mean follow‐up 4 months, range 1‐24 months) Time points reported: complete follow‐up (mean follow‐up 4 months, range 1‐24 months) Subgroups: none Quality of life: not reported Ventricular size reduction: not reported Head circumference: not reported
Funding sources	Not available
Declarations of interest	Not available
Notes	This study reported a subjective clinical scale: "excellent" (normal function), "good" (few symptoms, independent in daily life activities), "regular" (greater symptoms, minor impairment in daily activities), "bad" (major impairment and dependent on continuous care including hospital care).
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	Quote: "a prospective randomised study" No other information available
Allocation concealment (selection bias)	Unclear risk	Quote: "a prospective randomised study" No other information available
Blinding of participants and personnel (performance bias) Subjective outcomes: treatment failure, adverse events, quality of life	High risk	No information about blinding available, however personnel was aware of the type of shunt being placed during the procedure
Blinding of participants and personnel (performance bias) Objective outcomes: mortality, head circumference, ventricular size	Low risk	No information about blinding available, however personnel was aware of the type of shunt being placed during the procedure. 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 personnel was aware of the type of shunt being placed during the procedure
Blinding of outcome assessment (detection bias) Objective outcomes: mortality, head circumference, ventricular size	Low risk	No information about blinding available, however personnel was aware of the type of shunt being placed during the procedure. Outcomes were likely to be unaffected by blinding.
Incomplete outcome data (attrition bias) All outcomes	Low risk	All outcomes: follow‐up data was complete for all participants.
Selective reporting (reporting bias)	Unclear risk	Insufficient information to permit judgement of ‘Low risk’ or ‘High risk’ (no protocol available)
Other bias	Low risk	No other sources of bias were identified.