Evaluation of a computer-assisted data entry procedure (including Teleform) for large-scale mailed surveys.

Computer-assisted data entry procedures for self-completion population surveys are previously unreported. We used Teleform for a questionnaire to registrants (aged 50+) with general practices in North Staffordshire, UK (n=8995). The survey achieved a 77% response rate. 98% (n=6647) of returned questionnaires were scannable. These questionnaires were checked (and corrected) before scanning for entries that may be inaccurately read by the software. Three percent of 1020 scanned questionnaires checked (0.041% of all questionnaire items) had a data entry error. Systematic processes enable accurate survey data transfer to be achieved with Teleform. However, many administrative and technical issues need addressing.