Methodological and economic evaluations of seven survey modes applied to health service research

Objective To evaluate methodological outcomes and cost‐effectiveness of seven survey modes, using a study of general public views towards pharmacy public health services. Methods A cross‐sectional, paper‐based survey was conducted in North West England among people aged ≥18 years, using two approaches. Three interviewer‐assisted modes were street, door‐to‐door and telephone. Four self‐completion modes were single‐ and double‐mailing to residential addresses, surveys sent to public/private business by post (postal‐business) and questionnaires dropped‐off at venues (drop‐off). The study compared response rates, demographics and two domains ((a) actual use of and (b) willingness to use pharmacy public health services) between modes. Incremental cost‐effectiveness ratios of different modes were assessed against the single‐mailing. Key findings Response rate varied between 5.1% (postal‐business) and 34.5% (street). Respondent age, education, employment, socioeconomic and deprivation status varied between different modes. Results for domain (a) were similar for all modes. Interviewer‐assisted modes resulted in more positive views on willingness to use advisory services ( P < 0.05). The drop‐off mode saved £45.92 ( US $72.55) per 1% increase in response rate compared to single‐mailing, while interviewer‐assisted and double‐mailing were more costly. At higher response rates, cost‐savings by the drop‐off mode diminished, but for other survey modes, additional costs decreased. Conclusion Drop‐off mode is cost‐effective compared to the standard single‐mailing, but selection bias is possible. Street surveys are also an efficient method, but may carry a higher risk of obsequiousness bias. Mixed‐modes surveys may reach wider sectors of the population. The similarity in use of services suggests all survey modes reach members of the public relevant to pharmacy researchers.