Bani 2014.

Methods	Cross‐over trial
Participants	Included: volunteer students with primary dysmenorrhoeal, age between 18 and 24, single, BMI = 19 to 25, a pain intensity score of 5 to 8 in the VAS, filled written consent, no history of abdominopelvic surgery, not prohibited from taking herbs and non‐steroidal anti‐inflammatory drugs (NSAIDs) (e.g. renal, hepatic, or gastrointestinal disease) Excluded: occurrence of a stressful event (e.g. bereavement), using drugs that might interact with NSAIDs, using oral contraceptive pills and lack of compliance Age: mean age of intervention group = 22.2 years; mean age of control group = 22.1 years Source: dormitories of Tabriz University of Medical Sciences Location: Iran
Interventions	Group 1: Rosa damascena extract capsule* 200 mg (N = 46) Group 2: mefenamic acid capsule (NSAIDs) 250 mg (N = 46) The participants in both groups were supposed to take one capsule every 6 hours during the first 3 days of menstruation (2 cycles) *The dried fruits of Rosa damascena were changed to powder by a mechanical grinder and the extraction was performed with ethanol 70% using the method of maceration
Outcomes	Pain intensity VAS (scale 10 cm): self‐reported at the time of menstrual pain (before taking the drug) and at 1, 2, 3, 6, 12, 24, 48, and 72 hours after menstrual pain started; side effects.
Notes	No wash out period We extracted data from the first phase (before cross‐over)
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	“The random allocation was done by www. Random.org site with blocking method (size of blocks: 4 and 6).”
Allocation concealment (selection bias)	Low risk	“The assistant put the drugs of each number in an envelope with the respective number written on the envelope and 92 envelopes were given to the researcher to pass them to the corresponding participants.”
Blinding (performance bias and detection bias) All outcomes	Low risk	“The capsules of Rosa damascena extract were produced with the same appearance, colour and odour as Mefenamic acid capsules” “During the study, the participants and the researcher were unaware of the drug”
Incomplete outcome data (attrition bias) All outcomes	Low risk	“In the present study, two groups of 46 persons participated (92 persons). All of them entered the statistical analysis and no sample loss happened.”
Selective reporting (reporting bias)	Low risk	Comment: the study authors reported a priori outcomes. Adverse effects were reported in both groups.
Other bias	Low risk	Comment: we did not identify any other potential sources of bias.