Connelly 2000.

Study characteristics
Methods	Randomised, double‐blind, placebo‐controlled trial Study type: single‐centre study Location: USA (Massachusetts) Study design: parallel Randomisation: computer random numbers series Allocation concealment: sealed container with a random code Blinding: blinding of participants and key study personnel Follow‐up period: 48 hours
Participants	Randomised: 10 (intervention group: 5; control group: 5) Excluded (post‐randomisation): not described Gender (women): 8 (80%); intervention group 3 (60%); control group 5 (100%) Age (years); mean (SD): intervention group 43 (12); control group 24 (8) Baseline VAS score: mean (SD): intervention group 61 (24), control group 87 (23) Inclusion criteria: Patients with severe PDPH Exclusion criteria: History of migraine, a contraindication to an EBP, or contraindication to sumatriptan (ischaemic heart disease, hypertension, pregnancy, pre‐eclampsia or being treated with ergot medications or MAO inhibitors)
Interventions	Intervention group: once subcutaneous sumatriptan, 6 mg (0.5 ml) Control group: once subcutaneous saline (0.5 ml) Co‐interventions: Conservative treatment (fluid hydration, bed rest and caffeine beverages) for at least 12 hours prior to study participation EBP if headache remained severe after 1 hour
Outcomes	Number of participants with EBP performed Change in pain severity VAS score after 1 hour Number of participants showing improvements in pain severity
Notes	Post‐dural puncture headache (PDPH): Quote "Headache which is characterized by relieved with recumbency". (Page 316) Visual analogue scale (VAS): 0 = no headache and 100 = worst headache imaginable Sample size calculation: not described Email contact with MD Neil Roy Connelly on January 2010 for clarification about randomisation, allocation concealment, blinding and statistical questions
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	The investigator reported the use of a computer random number generator
Allocation concealment (selection bias)	Low risk	The investigator reported the use of a sealed container with a random code
Blinding (performance bias and detection bias) All outcomes	Low risk	Quote: "Patients received, in a randomised fashion, either subcutaneous sumatriptan, 6 mg (0.5 mL), or saline (0.5 mL) using the Glaxo injector". (Page 317) The investigator reported blinding the VAS recorder
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 outcomes (PDPH persistence of any severity at follow‐up and number of any possible adverse events) that would be expected to have been reported for such a study
Size of study	High risk	Total 10 (intervention group: 5; control group: 5)