Su 1997.

Methods	Randomised, double‐blind, placebo‐controlled, crossover trial
Participants	Country: USA Site: No details Recruitment: Self referred in response to local advertisements or referred by physicians. Nineteen randomised (17 completed). Refer to Table of bias for details of attrition. Mean age 36.5±5.4 years Inclusion: Absence of significant medical illness, absence of significant Axis 1 psychiatric illness, including alcohol and substance misuse. Not taking psychoactive medications, hormonal preparations (including oral contraceptives), mineral supplements, or non‐steroidal anti‐inflammatory medications within the past 6 months. Regular menstrual cycles (23‐35 days). Confirmed diagnosis of PMS via a prospective daily 3 item VAS. >30% increase in mean negative mood symptoms, relative to the actual range of the analogue scale used, in the week before menses compared with the week after menses in at least two out of three cycles. Required to use barrier methods of contraception. Exclusion: Appearance of significant mood symptoms during the follicular phase.
Interventions	Screening: Three cycles of screening Placebo run in: None Intervention: Crossover trial of 20mg fluoxetine every day cycle 1, 20‐60mg every day for 2 further cycles (mean drug dose during cycle 3 was 29.9±10.6mg) versus placebo. At end of first arm there was one cycle washout period Timing of administration: Medication started on the first day of menses and continued for a full menstrual cycle Summary measures: Results of pre and post menstrual weeks were averaged for the three cycles in each condition in the paper. Composite scores calculated for mood symptoms and social impairment symptoms in paper
Outcomes	Weekly means of 16 item visual analogue scale (VAS) and 21 item daily rating form (DRF) during seven days before and seven days after menses. Beck Depression Inventory (BDI); State Trait Anxiety Inventory ‐ State form (STAI); Rating Scale for Pre Menstrual Tension (PMTS self and PMTS observer); Physical symptom checklist; Adverse events
Notes	10 women given m‐CPP (serotonin agonist) during follicular and luteal phase. Women who responded to m‐CPP challenge responded to fluoxetine Unable to extract first arm data from paper Daily symptom rating Fluoxetine provided by Eli‐Lilly
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	Not reported
Allocation concealment (selection bias)	Unclear risk	Not reported
Blinding (performance bias and detection bias) All outcomes	Low risk	Double blind (patient and rater)
Incomplete outcome data (attrition bias) All outcomes	Low risk	17/19 women randomised were included in analysis (89%) . Nineteen were enrolled in study and seventeen completed. Two women in treatment arm dropped out due to intolerable migraine headaches (n=1) and unrelated irregular menstrual bleeding (n=1) no details as to which arm of the crossover this occurred in
Selective reporting (reporting bias)	Unclear risk	Does not state how adverse effects data collected
Other bias	Low risk	No potential source of other bias identified. Crossover study with one month washout period