Participants and Procedure
Data were collected at six homeless shelters between July and August 2016 in the Oklahoma City area. Homeless individuals were eligible to participate in this study if they met the following criteria: 1) earned a score ≥ 4 on the Rapid Estimate of Adult Literacy in Medicine-Short Form (REALM-SF(20)) indicating > 6th grade English literacy level, 2) were ≥ 18 years of age, and 3) were receiving services at the targeted shelters.
Flyers advertising for this study and sign-up times were posted around shelter campuses. Individuals who were interested in the study were given a screening appointment, and they received detailed information about the study during that appointment. Those who remained interested in participating were screened for study inclusion. Those who qualified for the study completed a tablet-based 1.5-hour survey. Participants who completed the assessments received a $20 gift card as compensation. The study procedure was approved by the Institutional Review Board at the University of Oklahoma Health Sciences Center. Details of the study design are described elsewhere.(21–23)
Measures
Demographics. All participants completed assessments of demographic characteristics, including age, sex, race, marital status, and years of education.
Three homelessness subgroups. Participants were asked, “Where did you sleep last night?” Based on their response, participants were divided into three categories: (3, 24) 1) sheltered homeless (homeless shelter and/or drug or alcohol treatment center), 2) unsheltered homeless (outside or on the street), and 3) unstably housed (friend’s or family member’s house or apartment, hotel or motel, other temporary location).
Incarceration history and victimization. Incarceration history was assessed using two items, “Have you been incarcerated (jail or prison) in the past year?”, and response options were yes (1) or no (0). Participants were also asked, “During your lifetime, how much time have you spent in jail or prison?”, and the responses were calculated in months.
Shelter-based service utilization. Shelter-based utilization of mental health services was assessed via four questions, “Over the past 3 months, have you received Mental Health/Behavioral Health Counseling at local shelters?”, “Over the past 3 months, have you received Substance Abuse Counseling at local shelters?”, “Over the past 3 months, have you received any meals at local shelters?”, and “Over the past 3 months, have you met a case manager at local shelters?”, and response options were yes (1) or no (0).
Health risk factors. Physical activity in the past week, sleep, binge drinking in the past month, drug use yesterday, and obesity were assessed. Physical activity was assessed using two items to determine whether, in a usual week, participants participated in moderate-intensity physical activities such as brisk walking, bicycling, vacuuming, or gardening, and/or vigorous-intensity physical activities such as running, aerobics, or heavy yard work. Respondents who indicated that they did moderate- or vigorous-intensity physical activity were also asked to report how many days per week they spent at least 10 minutes at a time doing the activities, and how much total time (in minutes) per day they spent doing the activities. After vigorous minutes were multiplied by 2, total physical activity minutes were multiplied by the number of days per week to refer to participants’ total minutes spent in moderate-to-vigorous physical activity (MVPA) in the past week (25). Sleep deprivation was measured by the responses (yes or no) to the question, “I do not get enough sleep.” Binge drinking status was assessed by asking a question, “How often in the past 30 days have you consumed [5 for men/ 4 for women] or more standard drinks?(26)” The responses were dichotomized as “binge drinking in the past 30 days” vs. “no binge drinking in the past 30 days.” Drug use was assessed by asking one question, “Please select all the substances that you used yesterday (check all that apply).” Answers were dichotomized into any drug use yesterday (e.g., Cannabis, Cocaine, K2, and Amphetamine) and no drug use yesterday. BMI was calculated based on weight and height, and participants were categorized into underweight or normal (0), and overweight or obese (1) (27).
Stressors. Level of life stress was assessed using the Urban Life Stress Scale, which is a 21-item self-report checklist of potential sources of chronic stress (28). The degree of stress experienced related to each item was rated on a 5-point scale, from 1, “no stress at all,” to 5 “extremely stressful - more than I can handle.” The USDA Food Security Survey (29) was used to measure food insecurity during the last 12 months. This measure consists of 5 items (e.g., in the last 12 months, you could not afford to eat balanced meals) scored from 0 to 6.
Statistical Analyses
Comparisons between three homeless subgroups (i.e., sheltered homeless vs. unsheltered homeless vs. unstably housed) were made using Chi-square tests for categorical variables (e.g., race) or one way ANOVA for continuous variables (e.g., age) with Fisher's Least Significant Difference post-hoc test, as appropriate. The main predictor was the category of three homeless subgroups, and outcomes were shelter-based service utilization, stress measures, and the presence of specific health risk factors. Multiple linear regression was used to examine the relations between homeless subgroups and continuous outcomes (e.g., the Urban Life Stress Scale), and logistic regression was used for binary outcomes (e.g., binge drinking last month: yes or no) adjusting for covariates (i.e., age, sex, years of education, and race). All analyses were performed using SPSS version 25.