Kissinger 2006.

Methods	Setting: the Orleans Women's Health Clinic in New Orleans, US Enrolment: participants enrolled from December 2001 to August 2004 Follow‐up: participants were asked to return 4 weeks after the initial visit (with a window of 2‐8 weeks)
Participants	463 index patients with a culture‐confirmed diagnosis of Trichomonas vaginalis were randomised Inclusion criteria Women Culture‐confirmed Trichomonas vaginalis diagnoses Not in first trimester of pregnancy No medical contraindication to take metronidazole or bringing metronidazole to partner At least 1 male sexual partner in the last 60 days Exclusion criteria No criteria specified
Interventions	Study staff counselled women in all study arms about T. vaginalis and the importance of partner treatment before randomisation Simple patient referral (n = 155) Index patients were instructed to tell their partners that they need to go to a clinic for STI evaluation and treatment Booklet enhanced partner referral (n = 154) Index patients were given a wallet‐sized booklet containing tear‐out cards with information for the partner and treatment guidelines for providers EPT (n = 154) Index patients were given packages for their partners, containing medicine, written instructions on how to take medicine, warnings about side effects and nurse's pager number for enquiries
Outcomes	Re‐infection rate of index patient (T. vaginalis culture) PN (self report index patient ‐ interview) Partner treatment (self report index patient) Having unprotected sex before partner took medication (self report index patient) Re‐initiated sex with baseline partner (self report index patient) Unprotected sex with any partner (self report index patient) Cost effectiveness
Notes	Ethical approval from Institutional review board from Tulane University Health Sciences Center, CDC and the Louisiana Office of Public Health Author was contacted and provided details on consent (oral) and exact numbers of how many women returned for follow‐up and testing. Details to what intervention arm the woman with re‐infection belonged to was also provided
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	Blocked scheme of 3 or 6 units using Microsoft Excel
Allocation concealment (selection bias)	Unclear risk	Previously prepared envelopes. Not specified if these were sealed or identical
Incomplete outcome data (attrition bias) All outcomes	Low risk	412/463 (89%) index patients were re‐interviewed (some interviews done by telephone, and, therefore, no sample submitted) but only 376/463 (81%) index patients were retested and re‐interviewed (data from author directly)
Selective reporting (reporting bias)	Unclear risk	Protocol available from trial registries Outcomes stated in the protocol: Primary ‐ Index patient report of partner taking medicine at 6‐8 weeks Secondary ‐ Index patient re‐infection at 6‐8 weeks, cost‐effectiveness outcomes Outcome reported in actual study: Outcomes were not reported as primary and secondary. Additional sexual and behavioural outcomes reported Re‐interview scheduled for 4 weeks after treatment (window of 2‐8 weeks) Outcome in method section same as results section but differs from protocol
Other bias	Low risk	No other bias identified
Blinding of participants and personnel (performance bias) All outcomes	High risk	Participant and personnel not blinded
Blinding of outcome assessment (detection bias) All outcomes	High risk	No blinding Although some outcomes were subjective, the outcome of interest in the telephone interview was the response to this question: "Did partner tell you that he took the medicine?" Different methods were used for outcome assessment (i.e. telephone or computer‐assisted self interview) that may have introduced detection bias, outcomes assessors were unlikely blinded Assessment of T. vaginalis culture result was not blinded but is an objective outcome