Rietz 2002.

Methods	Design: cross‐sectional cohort study Study dates: June to December 2000 Malaria transmission pattern and local antimalarial drug resistance: various, not specified Adverse event monitoring: patient self‐reported questionnaire
Participants	Number enrolled: 491 Inclusion criteria: "visitors over fifteen who were travelling to South or Central America, Africa, India or South‐East Asia, including China, and who were not suffering from any chronic illness" Exclusion criteria: none mentioned Factors influencing drug allocation: "After talking to the doctor, the doctor wrote whether malaria prophylaxis had been decided on and if so which kind" Country of recruitment: Sweden Region of malaria exposure: various, including South or Central America, Africa, India or Southeast Asia, including China Duration of exposure to malaria: "most were abroad between two to four weeks" Type of participants: travellers
Interventions	Included in the review: 1. Mefloquine* 2. Chloroquine* 3. Non‐users Not included in the review: 4. Chloroquine‐proguanil* *dosing regimen not specified
Outcomes	Included in the review: 1. Adverse events; any, seriously negative effect on the journey 2. Adverse effects; any 3. Adverse effects; other (neuropsychiatric, skin problems) Outcomes assessed not included in the review: 4. Importance attached to prophylaxis 5. Whether travellers had any anxiety about side effects prior to taking prophylaxis
Notes	Funding sources: not mentioned
Risk of bias
Bias	Authors' judgement	Support for judgement
Other bias	Unclear risk	1. Confounding: moderate Age, sex, destination and duration of travel data were collected but not reported across groups. BMI was not measured 2. Selection of participants into the study: serious Response rate 62% 3. Measurement of interventions: low The prescription was provided by a travel clinic which also performed the study 4. Departures from intended interventions: moderate Discontinuations were reported, but not across groups. Switches were not recorded 5. Missing data: low All participants who completed both questionnaires were included in the analysis 6. Measurement of outcomes: moderate The outcome measure was subjective; participants and personnel were not blinded. Participants were asked to report all symptoms, and which they felt were due to prophylaxis 7. Selection of the reported results: moderate Symptoms were grouped to report outcomes 8. Other: low Source of funding not mentioned. "competing interests: none declared"