Perry 1998.

Study characteristics
Methods	Design: Randomized controlled cross‐over trial (individually randomized) Trial dates and duration: Dates not stated, cross‐over after 12 days.
Participants	Number of participants: 76 Inclusion criteria: Clinically healthy commercial sex workers and students aged 18 to 50 years. Half were HIV‐positive and half were age and sex matched HIV‐negative. Exclusion criteria: Pregnancy; clinical symptoms of AIDS; previous cholera vaccination; reported having previously had cholera; taken antibiotics within the previous 4 days; current diarrhoea or other acute illness
Interventions	vaccine: CVD 103‐HgR live attenuated vaccine containing: 5 x 109 CFU of a genetically modified V. cholerae O1 Placebo: Lactate and aspartame only (these are also constituents of the vaccine) On day 12 those who initially received the placebo now received the vaccine, and vice versa.
Outcomes	Included in the review: Adverse events (Active surveillance; daily visits by physicians every day for 6 days and every other day for a further 6 days. Only adverse events prior to crossover are included) Not included in the review: Rectal swabs for vaccine virus on days of inoculation, daily for 4 days and on days 6 and 12 Immunological outcomes: Goemetric mean vibriocidal antibodies pre and post vaccination. Seroconversion rates (criteria not stated)
Notes	Location: Mali Setting: Not clear Source of funding:WHO Global Programme on Vaccines, National Institute of Allergy and Infectious Diseases, Centre for Vaccine Development, University of Maryland School of Medicine
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	Comment: Described as 'randomized', no further details given
Allocation concealment (selection bias)	Unclear risk	Comment: Not described
Blinding (performance bias and detection bias) Efficacy outcomes	Unclear risk	Not applicable as efficacy not reported
Blinding (performance bias and detection bias) Safety outcomes	Low risk	Quote: 'identically appearing placebo packets'
Incomplete outcome data (attrition bias) Efficacy outcomes	Unclear risk	Not applicable as efficacy not reported
Incomplete outcome data (attrition bias) Safety outcomes	Low risk	Comment: Four (6%) participants were lost to follow‐up during the study
Selective reporting (reporting bias)	Low risk	No evidence of selective outcome reporting
Other bias	Low risk	No other sources of bias identified