Title: Potentially Traumatic Event Experiences and Health Care Service Use in Liberia
Description: Several studies in high-income countries (HIC) have shown that the experience of potentially traumatic events (PTE) is associated with increased health care service use. Information on patterns of health care use and expectations by this group of individuals can be useful for providing patient-centric care and improving health system accountability and responsiveness. Despite the necessity of this work, less research has been conducted in low and lower-middle income countries (LIC; LMIC), especially in countries with a recent history of conflict, which is problematic for several reasons. Experience of PTEs, especially assaultive violence and injuries, may be higher in LICs and LMICs compared to HICs, which may lead to poor physical and mental health and increased demand for health care services. The formal health care system in LICs and LMICs, especially in those countries emerging from conflict, however, may be in a process of renewal and improvement. Many necessary health services may remain unavailable for several years during this process, accountability is often lacking, and the health system may not have the capacity to respond to health care needs.

Likely stemming from this lack of formal care, many LICs and LMICs have substantial informal care markets, and most individuals view both systems as complementary, despite the complete lack of regulation and training of informal care providers compared to formal care providers. In order for the formal care system to improve accountability and responsiveness, studies that assess the relation between PTE experience and use of both informal and formal care as well as patient preferences for formal care are critical. Such studies would shed light on where individuals with PTE experience are seeking care and what they expect from formal care. I conducted three investigations in order to better understand the association between experience of PTEs and health care service use in LICs and LMICs. In chapter one, I designed a systematic review of studies published on the topic using data from LICs and LMICs. I found only two studies that met eligibility criteria and suggested several considerations that future studies make, including the use of validated scales to measure PTE experience and the importance of including informal care use in this research.

In chapter two, using cross-sectional, population-based data on adults from Nimba County, Liberia, I assessed the relation between lifetime PTE experience and formal and informal care service use. Lifetime PTE experience increased both formal and informal care use and most persons who experienced PTEs likely complemented their formal use with informal use. One exception to this latter finding was a small group of individuals who used no informal care, among whom a higher number of PTEs was associated with using formal care. In chapter three, using data from a discrete choice experiment carried out on the same sample of adults from Nimba county, I found that those with increased experience of PTEs had a higher preference for a facility that offered a high quality exam, had a lower preference for respectful treatment, and a higher preference for seeing a traditional healer instead of using the facility to obtain care when sick. Most individuals with increased experience of PTEs used both the informal and formal care system to meet their health care needs.

Their reliance on the informal care system may be partially explained by symptoms of psychopathology, poor physical health, easier access to medications, and dissatisfaction with the formal care system. Higher preferences for a high quality medical exam and the traditional healer compared to formal clinics among those with high PTE experience suggest that the expectations of those arguably most in need of health care may not currently be met by the formal care system. Considering that informal care providers are untrained and unregulated, they are unlikely to provide adequate health care that can decrease disease burden in the population. It is likely that use of informal care reflects inadequate formal care; the formal care system must become more responsive to the needs of those with PTEs. There are several factors related to the PTE experience - health care use relation that merit further attention as well as several improvements that the formal care system should consider. One factor is whether mental health is a central reason why those with PTEs seek informal care.

Currently, formal care providers in Liberia are unable to adequately treat mental health problems, which may be one reason why individuals rely on informal care providers. Whether this is a determinant of informal care use should be assessed by future studies as, if this is the case, then any referral program in which informal providers refer patients to formal care may not prove successful. Training formal care providers in treating mental health problems should be implemented, but another aspect that merits further research is whether informal care providers like traditional healers can be trained to screen for mental health problems or provide limited counseling services for individuals prior to giving referrals to alleviate some of the burden on formal care. Another aspect of future research should compare the access, perceptions, and expectations of both care systems of those who use only formal care to those who use both. Identifying whether these individuals have better access to formal care, whether they view formal care differently, or whether they have less access to informal care may improve formal care system responsiveness.

Lastly the government of Liberia should continue improving access to the nearest facility, training providers to perform better exams, and improving the quality of clinics, including increasing the availability of medications and decreasing wait times, as these changes will likely increase use of formal care services by those with PTEs as well as the larger population.