Alahuhta 1990.

Methods	Treatment allocation: Women randomly assigned to receive spinal or epidural anaesthesia, no other details of methodology given. Allocation concealment: No details given. Documentation of exclusions: No exclusions. Blinding of outcome assessment: No blinding of outcome assessor ‐ "The patients were closely and continuously observed by the anaesthetists performing the blockade". Losses to follow up: None.
Participants	Inclusion criteria: 55 women undergoing elective caesarean section at university hospital in Finland. Inclusion criteria were term gestation with no medical or obstetric complications. Exclusions: None mentioned. Number lost to follow up: None.
Interventions	Spinal anaesthesia: 2.5 ml of 0.5% bupivacaine containing 8% glucose injected via a 25 G needle at L3‐4 in the sitting position. Women placed supine immediately after injection with wedge under right hip. Women excluded from study if analgesia did not reach T4‐5 30 minutes after injection. Epidural anaesthesia: 0.5% bupivacaine, 2 ml test dose followed by 14‐20 ml main dose via epidural catheter inserted with 18 G Tuohy needle in the left lateral position. Bupivacaine added until analgesia reached T4‐5. All women received 1000 ml of a balanced electrolyte solution before institution of regional blockade. A further 10 ml/kg was infused during onset of the blockade. All women asked frequently about pain during surgery and pain severity was recorded on a standard visual analogue scale. Medication was used during surgery to relieve pain, discomfort, anxiety and nausea, and to restore blood pressure.
Outcomes	Number of women failing to achieve adequate anaesthesia to begin surgery was recorded. Adequate anaesthesia being defined as "a T4‐5 level of analgesia 30 minutes after injection….". Number of women receiving additional analgesia during surgery was recorded. Degree of pain measured by standard visual analogue scale, pethidine iv given for analgesia. Number of women requiring treatment for hypotension was recorded. Hypotension defined as systolic blood pressure < 100 mmHg or fall of > 30% of control value. This was treated by increasing the infusion of balanced electrolyte solution and/or giving 5 mg iv bolus(es) of ephedrine. Other interventions for amnesia, nausea and bradycardia were mentioned. Onset times for analgesia to reach T6 were recorded. Postoperative follow up for post‐dural puncture headache was recorded but no treatment was mentioned. Follow up for Horner's syndrome and backache was mentioned.
Notes	Finland.
Risk of bias
Bias	Authors' judgement	Support for judgement
Allocation concealment (selection bias)	Unclear risk	B ‐ Unclear