Background:
Epidemiological research often requires collection of data from a representative sample of thecommunity or recruitment of specific groups through broad community approaches. Thepopulation coverage of traditional survey methods such as mail-outs to residential addresses,and telephone contact via public directories or random-digit-dialing is declining and surveyresponse rates are falling. There is a need to explore new sampling frames and considermultiple response modes including those offered by changes in telecommunications andinternet technology.
Methods:
We evaluated response rates and cost-effectiveness for three modes of survey administration(postal invitation/postal survey, postal invitation/internet survey and postalinvitation/telephone survey) and two styles of contact approach (personalised and generic) ina community survey of greywater use. Potential respondents were contacted only once, withno follow up of non-responders.
Results:
The telephone survey produced the highest adjusted response rate (30.2%), followed by thepersonalised postal survey (10.5%), generic postal survey (7.5%) and then the internet survey(4.7% for the personalised approach and 2.2% for the generic approach). There were somedifferences in household characteristics and greywater use rates between respondents todifferent survey modes, and between respondents to personalised and generic approaches.These may be attributable to the differing levels of motivations needed for a response, andvarying levels of interest in the survey topic among greywater users and non-users. Thegeneric postal survey had the lowest costs per valid survey received (Australian $22.93),followed by the personalised postal survey ($24.75).
Conclusions:
Our findings suggest that postal surveys currently remain the most economic option forpopulation-based studies, with similar costs for personalised and generic approaches. Internetsurveys may be effective for specialised groups where email lists are available for initialcontact, but barriers other than household internet access still exist for community-basedsurveys. Given the increasing recruitment challenges facing community-based studies, thereis an imperative to gather contemporary comparative data on different survey modes andrecruitment approaches in order to determine their strengths, limitations and costs.Researchers also need to document and report on the potential biases in the target andrespondent populations and how this may affect the data collected.