This study was designed as a multicenter retrospective questionnaire-based survey. The inclusion criteria were that participants planned to visit a malaria-endemic area and could complete the survey within 2 months of return. They also needed to have a permanent personal email address that they would access on return from travel and were above 18 years of age. Prior to travel, all participants attended a travel clinic run by a nurse or physician with a particular interest in travel medicine. To this end, the participating clinics were drawn from the membership of the British Global and Travel Health Association who were running clinics and had agreed to participate following an email to all members. Two further general practices where there was a well-established travel clinic in operation were also recruited. The study period ran from October 2011 to October 2012.
All travelers who attended the clinics and met the broad inclusion criteria were offered an information sheet inviting them to participate in the study, which was supplemented by verbal information from the clinic nurse if they agreed to take part. If they agreed to participate at that point they were only asked to supply their first name, email address, and month of return from the malaria-endemic area, be that to the UK or other country of origin. On the last day of their month of return participants were sent an email containing a link to an online questionnaire (SurveyMonkey) and again asked for their consent before completing. An email reminder was sent to all participants 1 month later.
The project was approved by the Nottingham 1 Ethics Committee, and separate UK National Health Service Research and Development approval was obtained for each of the individual sites.