| Author, date and country | Patient group | Study type (level of evidence) | Outcomes | Key results | Study weaknesses |
|---|---|---|---|---|---|
| Supervia A et al, Spain, 1998 | 80 sequential patients with a clinical diagnosis of renal colic confirmed by either urine analysis or ultrasound. | Double blind randomised controlled trial | Pain as measured by visual analogue score at 30 minutes | Both treatments significantly reduced pain scores at 30 minutes post administration. No significant difference evident between treatments in terms of efficacy of pain relief. | Relatively small numbers with no power study so possible type II error. |