Smith, RD; (2006) It's not just what you do, it's the way that you do it: the effect of different payment card formats and survey administration on willingness to pay for health gain. Health economics, 15 (3). pp. 281-93. ISSN 1057-9230 DOI: https://doi.org/10.1002/hec.1055 Full text not available from this repository.

Morris-Cunnington, MC; Edmunds, WJ; Miller, E; Brown, DWG; (2004) A novel method of oral fluid collection to monitor immunity to common viral infections. Epidemiology and infection, 132 (1). pp. 35-42. ISSN 0950-2688 DOI: https://doi.org/10.1017/s0950268803001493

Edwards, P; Roberts, I; Clarke, M; DiGuiseppi, C; Pratap, S; Wentz, R; Kwan, I; (2002) Increasing response rates to postal questionnaires: systematic review. BMJ (Clinical research ed), 324 (7347). pp. 1183-5. ISSN 0959-8138 DOI: https://doi.org/10.1136/bmj.324.7347.1183

Morris, MC; Edmunds, WJ; Miller, E; Brown, DWG; (2002) Oral fluid collection by post - a pilot study of two approaches. Public health, 116 (2). pp. 113-119. ISSN 0033-3506 DOI: https://doi.org/10.1038/sj.ph.1900833 Full text not available from this repository.

Smeeth, L; Fletcher, AE; (2002) Improving the response rates to questionnaires - Several common sense strategies are effective. BMJ, 324 (7347). pp. 1168-9. ISSN 1468-5833 DOI: https://doi.org/10.1136/bmj.324.7347.1168

Smeeth, L; Fletcher, AE; Stirling, S; Nunes, M; Breeze, E; Ng, E; Bulpitt, CJ; Jones, D; (2001) Randomised comparison of three methods of administering a screening questionnaire to elderly people: findings from the MRC trial of the assessment and management of older people in the community. BMJ (Clinical research ed), 323 (7326). pp. 1403-7. ISSN 0959-8138 https://researchonline.lshtm.ac.uk/id/eprint/17002