Impact of different privacy conditions and incentives on survey response rate, participant representativeness, and disclosure of sensitive information: a randomized controlled trial

BMC Medical Research Methodology

Melissa Ruth Partin³  Siamak Noorbaloochi³  Joseph Patrick Grill²  Ann Kay Bangerter²  Melissa Anderson Polusny¹  Alisha Baines Simon²  Maureen Murdoch³ 

[1] Department of Psychiatry, University of Minnesota School of Medicine, Minneapolis, MN, USA;Center for Chronic Disease Outcomes Research, Minneapolis VA Medical, One Veterans Drive, Minneapolis, MN 55417, USA;Department of Internal Medicine, University of Minnesota School of Medicine, Minneapolis, MN, USA

关键词: Confidentiality;    Anonymity;    Non-response bias;    Participation bias;    Patient surveys;    Randomized trial;   

Others  :  869764
DOI  :  10.1186/1471-2288-14-90

 received in 2014-03-03, accepted in 2014-07-07,  发布年份 2014

【 摘 要 】

Background

Anonymous survey methods appear to promote greater disclosure of sensitive or stigmatizing information compared to non-anonymous methods. Higher disclosure rates have traditionally been interpreted as being more accurate than lower rates. We examined the impact of 3 increasingly private mailed survey conditions—ranging from potentially identifiable to completely anonymous—on survey response and on respondents’ representativeness of the underlying sampling frame, completeness in answering sensitive survey items, and disclosure of sensitive information. We also examined the impact of 2 incentives ($10 versus $20) on these outcomes.

Methods

A 3X2 factorial, randomized controlled trial of 324 representatively selected, male Gulf War I era veterans who had applied for United States Department of Veterans Affairs (VA) disability benefits. Men were asked about past sexual assault experiences, childhood abuse, combat, other traumas, mental health symptoms, and sexual orientation. We used a novel technique, the pre-merged questionnaire, to link anonymous responses to administrative data.

Results

Response rates ranged from 56.0% to 63.3% across privacy conditions (p = 0.49) and from 52.8% to 68.1% across incentives (p = 0.007). Respondents’ characteristics differed by privacy and by incentive assignments, with completely anonymous respondents and $20 respondents appearing least different from their non-respondent counterparts. Survey completeness did not differ by privacy or by incentive. No clear pattern of disclosing sensitive information by privacy condition or by incentive emerged. For example, although all respondents came from the same sampling frame, estimates of sexual abuse ranged from 13.6% to 33.3% across privacy conditions, with the highest estimate coming from the intermediate privacy condition (p = 0.007).

Conclusion

Greater privacy and larger incentives do not necessarily result in higher disclosure rates of sensitive information than lesser privacy and lower incentives. Furthermore, disclosure of sensitive or stigmatizing information under differing privacy conditions may have less to do with promoting or impeding participants’ “honesty” or “accuracy” than with selectively recruiting or attracting subpopulations that are higher or lower in such experiences. Pre-merged questionnaires bypassed many historical limitations of anonymous surveys and hold promise for exploring non-response issues in future research.

【 授权许可】

   
2014 Murdoch et al.; licensee BioMed Central Ltd.

【 图 表 】

【 参考文献 】

• [1]Kessler R, McGonagle K, Zhao S, Nelson C, Hughes M, Eshleman S, Wittchen H, Kendler K: Lifetime and 12-month prevalence of DSM-III-R psychiatric disorders in the United States: results from the national comorbidity study. Arch Gen Psychiatry 1994, 51:8-19.
• [2]Straus M, Gelles R: How violent are American families? Estimates from the National Family Violence Resurvey and other studies. In Physical violence in American families Risk factors and adaptations to violence in 8,145 families. Edited by Strauss M, Gelles R. New Brunswick: Transaction Publishers; 1992:95-112.
• [3]Resnick H, Kilpatrick D, Dansky B, Saunders B, Best C: Prevalence of civilian trauma and posttraumatic stress disorder in a representative national sample of women. J Consult Clin Psychol 1993, 61:984-991.
• [4]Moum T: Mode of administration and interviewer effects in self-reported symptoms of anxiety and depression. Soc Indic Res 1998, 45(1–3):279-318.
• [5]Richman WL, Kiesler S, Weisband S, Drasgow F: A meta-analytic study of social desirability distortion in computer-administered questionnaires, traditional questionnaires, and interviews. J Appl Psychol 1999, 84(5):754-775.
• [6]Rogers SM, Miller HG, Turner CF: Effects of interview mode on bias in survey measurements of drug use: do respondent characteristics make a difference? Subst Use Misuse 1998, 33(10):2179-2200.
• [7]Testa M, Livingston J, VanZile-Tamsen C: The impact of questionnaire administration mode on response rate and reporting of consensual and nonconsensual sexual behavior. Psychol Women Q 2005, 29:345-352.
• [8]Beebe T, Harrison P, Park E, McRae JJ, Evans J: The effects of data collection mode and disclosure on adolescent reporting of health behavior. Soc Sci Computer Rev 2006, 24(4):476-488.
• [9]Stander V, Olson C, Merrill L: Self-definition as a survivor of childhood sexual abuse among Navy recruits. J Consult Clin Psychol 2002, 70(2):369-377.
• [10]Ong A, Weiss D: The impact of anonymity of responses to sensitive questions. J Appl Soc Psychol 2000, 30(8):1691-1708.
• [11]Durant L, Carey M, Schroder K: Effects of anonymity, gender, and erotophilia on the quality of data obtained from self-reports of socially sensitive behaviors. J Behav Med 2002, 25(5):438-467.
• [12]Rolnick S, Gross C, Garrard J, Gibson R: A comparison of response rate, data quality, and cost in the collection of data on sexual history and personal behaviors. Mail survey approaches and in-person interview. Am J Epidemiol 1989, 129(5):1052-1061.
• [13]Campbell M, Waters W: Does anonymity increase response rate in postal questionnaire surveys about sensitive subjects? A randomised trial. J Epidemiol Community Health 1990, 44:75-76.
• [14]Biggar R, Melbye M: Responses to anonymous questionnaires concerning sexual behavior: a method to examine potential biases. Am J Public Health 1992, 82(11):1506-1512.
• [15]Asch D: Use of a coded postcard to maintain anonymity in a highly sensitive mail survey: cost, response rates, and bias. Epidemiol 1996, 7:550-551.
• [16]Dunne M, Martin N, Bailey J, Heath A, Bucholz K, Madden P, Statham D: Participation bias in a sexuality survey: psychological and behavioural characteristics of responders and non-responders. Int J Epidemiol 1997, 26(4):844-854.
• [17]Murdoch M, Kressin N, Fortier L, Giuffre P: Evaluating the psychometric properties of a scale to measure medical students’ career-related values. Acad Med 2001, 76(2):157-165.
• [18]Murdoch M, Polusny M, Hodges J, O’Brien N: Prevalence of in-service and post-service sexual assault among combat and noncombat veterans applying for Department of Veterans Affairs posttraumatic stress disorder disability benefits. Milit Med 2004, 169(May):392-395.
• [19]Coxell A, King MB: Male victims of rape and sexual abuse. Sex Marital Ther 1996, 11:297-308.
• [20]Edwards P, Roberts I, Clarke M, DiGuiseppi C, Pratap S, Wentz R, Kwan I, Cooper R: Methods to increase response rates to postal questionnaires. Cochrane Database Methodol Rev 2003., (4) Art. No.: MR000008. doi:000010.001002/14651858.MR14000008.pub14651852
• [21]Murdoch M, McGovern P: Development and validation of the Sexual Harassment Inventory. Violence Vict 1998, 13(3):203-216.
• [22]Murdoch M, Pryor J, Polusny M, Gackstetter GD, Cowper-Ripley D: Local social norms and military sexual stressors: Do senior officers’ norms matter? Milit Med 2009, 174(10):1100-1104.
• [23]Bernstein D, Fink L: Childhood Trauma Questionnaire: A Retrospective Self-Report. Manual. San Antonio: The Psychological Corp.; Harcourt Brace & Co; 1998.
• [24]Wolfe J, Kimerling R, Brown P, Chrestman K, Levin K: Psychometric review of the Life Stressor Checklist-Revised. In Measurement of Stress, Trauma, and Adaptation. Edited by Stamm B. Lutherville, MD: Sidran Press; 1996:198-201.
• [25]Janes G, Goldberg J, Eisen S, True W: Reliability and validity of a combat exposure index for Vietnam veterans. J Clin Psychol 1991, 47:80-86.
• [26]Berwick D, Murphy J, Goldman P, Ware JJ, Barsky A, Weinstein M: Performance of a five-item mental health screening test. Med Care 1991, 29(2):169-176.
• [27]Hammarberg M: Penn Inventory for posttraumatic stress disorder: psychometric properties. Psychol Assess 1992, 4(1):67-76.
• [28]Russell M, Martier S, Sokol R, Mudar P, Bottoms S, Jacobson S, Jacobson J: Screening for pregnancy risk-drinking. Alcohol Clin Exp Res 1994, 18(5):1156-1161.
• [29]Groves R, Singer E, Corning A: Leverage-Saliency Theory of survey participation: description and an illustration. Public Opin Q 2000, 64(3):299-308.
• [30]Murdoch M, Polusny M, Street A, Grill J, Baines Simon A, Bangerter A, Noorbaloochi S, Voller E: Sexual assault of male US Troops during the Gulf War I Era: prevalence and correlates among applicants for Department of Veterans Affairs PTSD disability benefits. Milit Med 2014, 179(3):285-293.
• [31]Halpern S, Karlawish J, Casarett D, Berlin J, Asch D: Empirical assessment of whether moderate payments are undue or unjust inducements for participation in clinical trials. Arch Intern Med 2004, 164(7):801-803.
• [32]Couper M, Singer E: The role of numeracy in informed consent for surveys. J Empir Res Hum Res Ethics 2009, 4:17-26.