Noyan 2007.

Study characteristics
Methods	Randomised, double‐blind, controlled trial Study type: single‐centre study Location: Iran (Tehran) Study design: parallel Randomisation: not described Allocation concealment: not described Blinding: blinding of participants and key study personnel Follow‐up period: 48 hours
Participants	Randomised: 60 (intervention group: 30; control group: 30) Excluded (post‐randomisation): not described Gender (women): 60 (100%) Age (years); mean (SD): 27.1 (3.45) Baseline VAS score: mean (SD): intervention group 9.20 (0.71); control group 9.07 (0.69) Inclusion criteria: 18 to 40 years ASA I and II Headache after spinal anaesthesia for caesarean section Exclusion criteria: Cluster headache, convulsion, cerebrovascular accident, pre‐eclampsia, eclampsia, high intracranial pressure, coagulopathy or previous neurologic disease
Interventions	Intervention group: 200 mg hydrocortisone intravenously as a bolus and 100 mg hydrocortisone every 8 hours for 48 hours Co‐interventions: All patients were treated conventionally: complete bed rest, hydration (serum dextrose saline 3 L/4 hours) and analgesics (acetaminophen 2 325 mg tablets every 6 hours and intravenous pethidine 50 mg every 12 hours)
Outcomes	Number of participants with EBP performed Change in pain severity VAS score after 6, 24 and 48 hours Number of any possible adverse events
Notes	Post‐dural puncture headache (PDPH): Quote "Headache after spinal anaesthesia". (Page 416) Visual analogue scale (VAS): 0 to 1 no headache; 2 to 4 mild headache, 5 to 7 moderate headache; 8 to 10 severe headache Sample size calculation: not described
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	No information provided. Described as randomised
Allocation concealment (selection bias)	Unclear risk	No information provided
Blinding (performance bias and detection bias) All outcomes	Low risk	Quote: "Parturient women and observer did not know which patient had received hydrocortisone". (Page 418)
Incomplete outcome data (attrition bias) All outcomes	Low risk	No missing outcome data
Selective reporting (reporting bias)	High risk	The study report fails to include results for a key outcome (PDPH persistence of any severity at follow‐up) that would be expected to have been reported for such a study
Size of study	High risk	Total 60 (intervention group: 30; control group: 30)