|Inclusion criteria||Exclusion criteria|
Self completed mail surveys including electronic surveys using fax, internet or email.|
Health care topic.
Minimum 100 participants.
Published in English.
Reported response rate.
|Telephone surveys, personal interviews and captive audience surveys.|
|Participants||Healthcare professionals including doctors, nurses, allied health professionals, such as pharmacists, dentists, occupational therapists, physiotherapists and radiographers.||Students, patients and general public.|
|Final response rate||Number of usable questionnaires (completed or partially completed questionnaires) returned after the final reminder, divided by the total number sent.|
|Number of survey participants||Studies were grouped into <250, 250-499, 500-749, 750-999, 1000-2499, > = 2500 participants.|
|Publication Type||Standard or electronic format.|
|Health professional||Doctor, nurse, allied health or mixed populations.|
|Country of study population||Studies were grouped into US, Canada, Australia/New Zealand, UK/Ireland, other European and other countries.|
|Questionnaire length||Time required to complete questionnaire was used as a proxy for questionnaire length and estimated 3 pages or 8 questions per minute. Studies were grouped as <10 minutes, 10-19 minutes and > = 20 minutes.|
|Number of reminders||
Studies were grouped into no reminders, 1 reminder, 2 reminders and 3-5 reminders.|
Reminders could be postal, telephone or electronic.
|Use of financial incentives||Cash or prize draw incentive.|
|Survey Type||Surveys were classified as electronic if they were distributed by solely electronic processes. Those using only postal distribution or a mixed postal and electronic design were classified as postal.|