Stiskal 1998.

Methods	Masking of randomisation: Yes Masking of intervention: Yes Masking of outcome assessment: Yes Complete follow up: No
Participants	Total of 106 patients enrolled. Bw 600‐1000 requiring intubation and 1001‐1250 grams with respiratory distress syndrome were eligible for inclusion in the study Group 1: 53 neonates with mean (SD) GA 26.1 (1.7) wk and mean (SD) Bw 861 (167) grams and Group 2: 53 neonates with mean (SD) GA 26.5 (1.7) wk and mean Bw 864 (175) grams
Interventions	Group 1; received 60 mg/kg/dose of a1PI over 5 minutes within first 24 hours of age and this dose was repeated on days 4, 7, 14 at standard times. Group 2: received equivalent volume of placebo (Human Albumin 5%) at the same times.
Outcomes	Incidence of CLD (oxygen dependency at 28 days) in survivors Incidence of CLD (oxygen dependency at 36 weeks PMA) Death or oxygen dependence at 36 weeks PMA Need for systemic steroid administration Age at final extubation Age off all respiratory support Duration of oxygen requirement Death before discharge
Notes
Risk of bias
Bias	Authors' judgement	Support for judgement
Allocation concealment (selection bias)	Low risk	Masking of randomisation: Yes
Blinding (performance bias and detection bias) All outcomes	Low risk	Masking of intervention: Yes Masking of outcome assessment: Yes
Incomplete outcome data (attrition bias) All outcomes	High risk	Complete follow up: No

GA = Gestational age
 CLD = Chronic lung disease
 Bw = Birth weight
 a1PI = alpha 1 proteinase inhibitor
 SD = standard deviation
 wk = weeks