Engaging military couples in marital research: does requesting referrals from service members to recruit their spouses introduce sample bias?

BACKGROUND: While enrolling dyads in research studies is not uncommon, there is limited literature on the utility of different recruitment strategies and the resulting selection biases. This paper examined two recruitment strategies used to enroll military couples in a longitudinal study, assessing the impact of both strategies on the representativeness of the final study sample. METHOD: Descriptive and bivariate analyses were conducted to 1) identify characteristics associated with spouse referral, 2) compare response rates based on recruitment strategy and assess whether recruitment strategy modified correlates of response propensity among spouses, and 3) assess whether referred spouse characteristics differed from non-referred spouses in the final sample. The study sample consisted of married US service members with 2-5 years of military service as of October 2011 and their spouses. RESULTS: Service members who referred their spouses to participate in the Millennium Cohort Family Study were more likely to be male, have children, serve in the Army, and have combat deployment experience than those who did not refer their spouse. Nearly two-thirds (n = 5331, 64.9%) of referred spouses participated in the Family Study, compared with less than one-third (n = 3458, 29.5%) of directly contacted spouses. Spouse characteristics also differed significantly between recruitment groups. CONCLUSIONS: Overall results suggest that minimal bias was introduced by using a referral recruitment methodology. Service members appeared to be more likely to refer their spouses if they perceived the research topic as relevant to their spouse, such that male service members with combat deployment experience were more likely to refer female spouses caring for multiple children. Referred spouses were significantly more likely to respond to the Millennium Cohort Family Study survey than those who were directly contacted; however, the overall success rate of using a referral strategy was less than recruiting spouses through direct contact. Differences between referred spouses and spouses contacted directly mirrored service member referring characteristics.

Smoking and drinking behaviors of military spouses: Findings from the Millennium Cohort Family Study.

INTRODUCTION: The associations between stressful military experiences and tobacco use and alcohol misuse among Service members are well documented. However, little is known about whether stressful military experiences are associated with tobacco use and alcohol misuse among military spouses. METHODS: Using 9872 Service member-spouse dyads enrolled in the Millennium Cohort Family Study, we employed logistic regression to estimate the odds of self-reported cigarette smoking, risky drinking, and problem drinking among spouses by Service member deployment status, communication regarding deployment, and stress associated with military-related experiences, while adjusting for demographic, mental health, military experiences, and Service member military characteristics. RESULTS: Current cigarette smoking, risky drinking, and problem drinking were reported by 17.2%, 36.3%, and 7.3% of military spouses, respectively. Current deployment was not found to be associated with spousal smoking or drinking behaviors. Communication about deployment experiences with spouses was associated with lower odds of smoking, but not with risky or problem drinking. Spouses bothered by communicated deployment experiences and those who reported feeling very stressed by a combat-related deployment or duty assignment had consistently higher odds of both risky and problem drinking. CONCLUSIONS: Our findings suggest that contextual characteristics about the deployment experience, as well as the perceived stress of those experiences, may be more impactful than the simple fact of Service member deployment itself. These results suggest that considering the impact of deployment experiences on military spouses reveals important dimensions of military community adaptation and risk.