Research Brief

The Health Related Behaviors Survey (HRBS) is the U.S. Department of Defense's (DoD's) flagship survey for understanding the health, health-related behaviors, and well-being of service members. Fielded periodically for more than 30 years, the HRBS includes content areas that might affect military readiness or the ability to meet the demands of military life. The Defense Health Agency asked the RAND Corporation to revise and field the 2018 HRBS among members of both the active component and the reserve component. This brief discusses findings for the reserve component.

This brief reviews results for physical health and functional limitations. Some of the results are also compared with Healthy People 2020 (HP2020) objectives established by the U.S. Department of Health and Human Services for the general U.S. population. Because the military differs notably from the general population (for example, service members are more likely to be young and male than is the general population), these comparisons are offered only as a benchmark of interest.

Chronic Conditions

The burden of chronic disease in the United States is substantial. Chronic diseases are the leading cause of death in the United States and account for most U.S. health care costs. The presence of chronic conditions is associated with functional, physical, social, and cognitive limitations and reduced quality of life.

The HRBS asked whether respondents had been told by a physician or other health professional during the past 12 months that they have high blood pressure; high blood sugar or diabetes; high cholesterol; asthma; angina or coronary heart disease; heart attack (also called myocardial infarction); back pain; or a bone, joint, or muscle injury or condition. Overall, 36.6 percent (confidence interval [CI]: 35.5–37.7) reported being told that they had at least one of these eight chronic conditions (Figure 1).

Figure 1. Physician-Diagnosed Chronic Conditions in Past 12 Months, by Service Branch

Any chronic condition Bone, joint, or muscle injury (including arthritis) Back pain High blood pressure High cholesterol
Total 36.6% 21.9% 21.6% 9.3% 6.8%
Air Force Reserve 32.7% 19.4% 17.6% 7.3% 6.3%
Air National Guard 32.0% 16.9% 17.8% 7.8% 6.6%
Army Reserve 40.1% 24.6% 24.4% 9.9% 7.8%
Army National Guard 37.3% 22.8% 22.2% 9.8% 6.4%
Marine Corps Reserve 32.5% 21.1% 23.9% 6.7% 3.5%
Navy Reserve 36.6% 20.4% 19.6% 10.7% 8.4%
Coast Guard Reserve 34.3% 17.6% 18.2% 7.2% 11.1%

The most commonly reported physician-diagnosed chronic condition was bone, joint, or muscle injury or condition, with 21.9 percent (CI: 21.0–22.8) reporting this. Back pain was the second most commonly reported condition, reported by 21.6 percent (CI: 20.7–22.5). High blood pressure was the third most commonly reported condition, reported by 9.3 percent (CI: 8.7–9.9). HP2020 goals seek to reduce the proportion of U.S. adults with high blood pressure to 26.9 percent. High cholesterol was the fourth most common condition, reported by 6.8 percent (CI: 6.3–7.2). HP2020 goals seek to reduce the proportion of U.S. adults with high cholesterol to 13.5 percent. Each of the other chronic conditions covered by the HRBS was reported by 2 percent or less of respondents.

Physical Symptoms

An estimated 34 percent of individuals in the general population report at least one frequent physical symptom, and one-third of physical symptoms are medically unexplained.[1] The presence of multiple physical symptoms is associated with greater rates of depression, anxiety, substance use disorders, and medical service use.

HRBS respondents completed a symptom checklist with eight common physical symptoms: stomach or bowel problems; back pain; pain in the arms, legs, or joints; headaches; chest pain or shortness of breath; dizziness; feeling tired or having low energy; and trouble sleeping. Respondents were asked how much they were bothered by each of these symptoms in the past 30 days.

Overall, 21.1 percent (CI: 20.2–22.0) reported that they were "bothered a lot" by one or more bodily pain symptoms, including headache. The most commonly reported individual symptom was trouble sleeping, with 13.7 percent (CI: 12.9–14.5) reporting that they were "bothered a lot" by this (Figure 2).

Figure 2. Pain Symptoms and Symptom Severity in Past 30 Days, by Service Branch

At least one pain symptom (including headaches) Trouble sleeping High physical symptom severity
Total 21.1% 13.7% 11.0%
Air Force Reserve 17.0% 9.0% 6.6%
Air National Guard 15.3% 9.0% 7.3%
Army Reserve 24.0% 14.3% 12.6%
Army National Guard 22.0% 15.4% 11.9%
Marine Corps Reserve 23.1% 16.3% 13.2%
Navy Reserve 21.0% 14.4% 11.1%
Coast Guard Reserve 17.6% 11.9% 8.1%

A high physical symptom severity score was calculated, with each symptom for each respondent as 0 (not bothered at all), 1 (bothered a little bit), or 2 (bothered a lot). Scores ranged from 0 to 16, and scores of 8 or higher indicated high physical symptom severity.[2] Overall, 11.0 percent (CI: 10.3–11.7) of respondents had high physical symptom severity.

Traumatic Brain Injury and Postconcussive Symptoms

Military service members are at risk for experiencing a range of physical injuries. Some factors potentially related to injury, such as physical training, are common in the military. Other potential contributors include vehicle crashes and sports injuries. Deployment also increases the risks of certain types of injury. These and other factors can place service members at increased risk for a traumatic brain injury (TBI).

The HRBS assessed TBI using three sets of items based on the Brief Traumatic Brain Injury Screen. It classified respondents as having mild traumatic brain injury (mTBI) if respondents reported one or more injuries in the past 12 months and recalled having lost consciousness for up to 20 minutes; feeling dazed, confused, or "seeing stars"; experiencing postconcussive symptoms; or lack of memory of the event. It classified respondents as having moderate to severe TBI if they reported loss of consciousness for more than 20 minutes. The HRBS classified respondents as having postconcussive symptoms if they screened positive for TBI and endorsed at least four postconcussive symptoms in the past 30 days.

Overall, 21.2 percent (CI: 20.2–22.1) of HRBS respondents reported an injury in the past year. Across all services, 4.3 percent (CI: 3.8–4.8) of reservists screened positive for mTBI, 0.2 percent (CI: 0.1–0.3) screened positive for moderate to severe TBI, and 2.7 percent (CI: 2.3–3.1) reported postconcussive symptoms.

Self-Rated Health

In addition to reporting on physical symptoms, service members were asked to self-report their overall physical health. Such measures have been shown to be valid measures of physical and emotional health and to predict all-cause mortality. Service members were asked to classify their health as excellent, very good, good, fair, or poor. Altogether, 57.3 percent (CI: 56.2–58.5) classified their health as excellent or very good.

Health-Related Functional Limitations

Chronic conditions and physical limitations can affect individuals' use of health care, quality of life, and ability to carry out normal daily responsibilities. This can result in reduced productivity and missed days of school or work.

The HRBS assessed absenteeism—that is, lost work or school days because of health symptoms—and presenteeism—that is, days present at work or school but with performance compromised because of health symptoms. Respondents were asked how many days in the past 30 their mental or physical symptoms caused them to miss school or work or to feel so impaired that, even though they went to school or work, their performance was compromised.

On average, service members reported 0.53 days (CI: 0.47–0.59) of absence from duty in the past 30 days (Figure 3). They also reported 1.50 presentee days (CI: 1.39–1.61) in the past 30 days.

Figure 3. Absenteeism and Presenteeism, by Service Branch

Average number of days in past 30

Absenteeism Presenteeism
Total .53 1.50
Air Force Reserve .24 .78
Air National Guard .35 .95
Army Reserve .63 1.64
Army National Guard .61 1.70
Marine Corps Reserve .38 1.91
Navy Reserve .54 1.54
Coast Guard Reserve .21 .81

Comparisons with the Active Component

To compare HRBS results for the active and reserve components, RAND researchers constructed regression models that control for demographic characteristics of the respondents. Significant differences identified for reservists relative to active component members included

  • lower likelihood of several physician-diagnosed chronic conditions: high blood pressure; back pain; and bone, joint, and muscle injury (including arthritis)
  • lower likelihood of having any physician-diagnosed chronic condition in the past year
  • lower likelihood of bodily pain and of high physical symptom severity
  • lower likelihood of traumatic brain injury and postconcussive symptoms
  • higher likelihood of reporting "excellent" or "very good" health
  • fewer days of missed work (absenteeism) and fewer days of reduced productivity (presenteeism) because of health symptoms.

Conclusions and Policy Implications

Pain was a commonly reported health condition by reservists. High levels of pain might be unsurprising given the physical demands associated with military service. Nevertheless, the potential for pain to reduce physical functioning or lead to health risks associated with prescription analgesic use, including opioids, makes this a potential area of military readiness concern. DoD, the services, and the Coast Guard should continue to place policy and program attention on both preventing injury and pain and emphasizing a variety of nonpharmacologic pain management approaches.

Notes

  • [1] J. I. Escobar, B. Cook, C. N. Chen, M. A. Gara, M. Alegria, A. Interian, and E. Diaz, "Whether Medically Unexplained or Not, Three or More Concurrent Somatic Symptoms Predict Psychopathology and Service Use in Community Populations," Journal of Psychosomatic Research, Vol. 69, No. 1, July 2010, pp. 1–8; K. Kroenke, "Patients Presenting with Somatic Complaints: Epidemiology, Psychiatric Comorbidity and Management," International Journal of Methods in Psychiatric Research, Vol. 12, No. 1, February 2003, pp. 34–43.
  • [2] Note, however, that there is no existing literature that validates this scoring against the probability of a clinical diagnosis; "high" in this sense reflects that the scoring pattern is relatively infrequent in the population.
  • [3] CIs provide a range in which the true population value is expected to fall. They account for sampling variability when calculating point estimates but do not account for problems with question wording, response bias, or other methodological issues that, if present in the HRBS, might bias point estimates.

This report is part of the RAND Corporation research brief series. RAND research briefs present policy-oriented summaries of individual published, peer-reviewed documents or of a body of published work.

Permission is given to duplicate this electronic document for personal use only, as long as it is unaltered and complete. Copies may not be duplicated for commercial purposes. Unauthorized posting of RAND PDFs to a non-RAND Web site is prohibited. RAND PDFs are protected under copyright law. For information on reprint and linking permissions, please visit the RAND Permissions page.

The RAND Corporation is a nonprofit institution that helps improve policy and decisionmaking through research and analysis. RAND's publications do not necessarily reflect the opinions of its research clients and sponsors.