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

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.

Local social norms and military sexual stressors: do senior officers' norms matter?

OBJECTIVE: To examine the relative importance of harassment-tolerant norms emanating from troops senior officers, immediate supervisors, and units on troops' sexual stressor experiences and to see whether associations differed by sex. METHOD: Cross-sectional survey of all 681 willing and confirmed active duty troops enrolled in the VA National Enrollment Database between 1998 and 2002. Findings extended an earlier analysis. RESULTS: After adjusting for other significant correlates, senior officers' perceived tolerance of sexual harassment was not associated with the severity of sexual harassment troops reported (p = 0.64) or with the numbers of sexual identity challenges they reported (p = 0.11). Harassment-tolerant norms emanating from troops' units and immediate supervisors were associated with reporting more severe sexual harassment and more sexual identity challenges (all p < 0.003). Findings generalized across sex. CONCLUSIONS: Senior officers' norms did not appear to affect troops' reports of military sexual stressors, but unit norms and immediate supervisors' norms did.

Functioning and psychiatric symptoms among military men and women exposed to sexual stressors.

OBJECTIVE: The goal was to describe military men's and women's functioning and psychiatric symptoms according to their military sexual stressor exposure. METHOD: A cross-sectional survey of 204 Army soldiers and 611 other active duty troops (487 men and 327 women) was performed. RESULTS: Forty-five percent of men and 80% of women reported at least one sexual stressor type (i.e., sexual identity challenges, sexual harassment, or sexual assault). After adjustment, subjects reporting more types of sexual stressors had poorer physical, work, role, and social functioning; more-severe post-traumatic stress disorder, depression, and anxiety symptoms; and more somatic concerns, compared with subjects reporting fewer or no sexual stressor types (all p < or = 0.004). Interactions by gender were insignificant (all p > 0.11). Within sexual stressor category, men and women reported similar mean adjusted functioning and psychiatric symptoms. CONCLUSIONS: For both men and women, impaired functioning and more severe psychiatric symptoms were more common among those reporting more types of sexual stressors.