Effect of reminders on mitigating participation bias in a case-control study

BMC Medical Research Methodology

Laura C Rodrigues¹  Craig D Higgins¹  Clarence C Tam¹ 

[1]Faculty of Epidemiology and Population Health, London School of Hygiene & Tropical Medicine, London, UK

关键词: community surveys;    respondents;    nonrespondents;    data collection;    survey methods;    epidemiologic methods;    case-control studies;    bias;   

Others  :  1140332
DOI  :  10.1186/1471-2288-11-33

 received in 2011-01-05, accepted in 2011-03-31,  发布年份 2011

【 摘 要 】

Background

Researchers commonly employ strategies to increase participation in health studies. These include use of incentives and intensive reminders. There is, however, little evidence regarding the quantitative effect that such strategies have on study results. We present an analysis of data from a case-control study of Campylobacter enteritis in England to assess the usefulness of a two-reminder strategy for control recruitment.

Methods

We compared sociodemographic characteristics of participants and non-participants, and calculated odds ratio estimates for a wide range of risk factors by mailing wave.

Results

Non-participants were more often male, younger and from more deprived areas. Among participants, early responders were more likely to be female, older and live in less deprived areas, but despite these differences, we found little evidence of a systematic bias in the results when using data from early reponders only.

Conclusions

We conclude that the main benefit of using reminders in our study was the gain in statistical power from a larger sample size.

【 授权许可】

   
2011 Tam et al; licensee BioMed Central Ltd.

【 图 表 】

Figure 1.

Figure 2.

【 参考文献 】

• [1]Shen M, Cozen W, Huang L, Colt J, De Roos AJ, Severson RK, Cerhan JR, Bernstein L, Morton LM, Pickle L, Ward MH: Census and geographic differences between respondents and nonrespondents in a case-control study of non-Hodgkin lymphoma. Am J Epidemiol 2008, 167(3):350-361.
• [2]Madigan MP, Troisi R, Potischman N, Brogan D, Gammon MD, Malone KE, Brinton LA: Characteristics of respondents and non-respondents from a case-control study of breast cancer in younger women. Int J Epidemiol 2000, 29(5):793-798.
• [3]Stang A, Ahrens W, Jockel KH: Control response proportions in population-based case-control studies in Germany. Epidemiology 1999, 10(2):181-183.
• [4]Edwards PJ, Roberts I, Clarke MJ, Diguiseppi C, Wentz R, Kwan I, Cooper R, Felix LM, Pratap S: Methods to increase response to postal and electronic questionnaires. Cochrane Database Syst Rev 2009, (3):MR000008.
• [5]Nakash RA, Hutton JL, Jorstad-Stein EC, Gates S, Lamb SE: Maximising response to postal questionnaires--a systematic review of randomised trials in health research. BMC Med Res Methodol 2006, 6:5. BioMed Central Full Text
• [6]Stang A, Jockel KH: Studies with low response proportions may be less biased than studies with high response proportions. Am J Epidemiol 2004, 159(2):204-210.
• [7]Kreiger N, Nishri ED: The effect of nonresponse on estimation of relative risk in a case-control study. Ann Epidemiol 1997, 7(3):194-199.
• [8]Voigt LF, Boudreau DM, Weiss NS, Malone KE, Li CI, Daling JR: Re: "Studies with low response proportions may be less biased than studies with high response proportions". American Journal of Epidemiology 2005, 161(4):401-402.
• [9]Tam CC, Higgins CD, Neal KR, Rodrigues LC, Millership SM, O'Brien SJ: Chicken consumption and use of acid-suppressing medications as risk factors for Campylobacter enteritis, England. Emerg Infect Diseases 2009, in press.
• [10]The English Indices of Deprivation 2004: Summary (revised) [http://www.rbkc.gov.uk/kcpartnership/General/pc_indices_deprivation.pdf] webciteLondon: The Office of the Deputy Prime Minister; 2004.
• [11]O'Mahony PG, Thomson RG, Rodgers H, Dobson R, James OF: Accuracy of the family health services authority register in Newcastle upon Tyne, UK as a sampling frame for population studies. J Epidemiol Community Health 1997, 51(2):206-207.
• [12]Sandler RS, Holland KL: Fate of incorrectly addressed mailed questionnaires. J Clin Epidemiol 1990, 43(1):45-47.
• [13]Schmidt-Pokrzywniak A, Stang A: Study of return rate and return time of undeliverable postal letters. Eur J Epidemiol 2010, 25(7):467-470.
• [14]Groves RM, Singer E, Corning A: Leverage-saliency theory of survey participation: description and an illustration. Public Opin Q 2000, 64(3):299-308.
• [15]Groves RM, Presser S, Dipko S: The Role of Topic Interest in Survey Participation Decisions. Public Opin Q 2004, 68(1):2-31.
• [16]Rogers A, Murtaugh MA, Edwards S, Slattery ML: Contacting controls: are we working harder for similar response rates, and does it make a difference? Am J Epidemiol 2004, 160(1):85-90.