Injury Patterns and Treatment Strategies in Civilian and Military Isolated Abdominal Gunshot Wounds.

BACKGROUND: Combat-related gunshot wounds (GSW) may differ from those found in civilian trauma centers. Missile velocity, resources, logistics, and body armor may affect injury patterns and management strategies. This study compares injury patterns, management, and outcomes in isolated abdominal GSW between military (MIL) and civilian (CIV) populations. METHODS: The Department of Defense Trauma Registry (DoDTR) and TQIP databases were queried for patients with isolated abdominal GSW from 2013 to 2016. MIL patients were propensity score matched 1:3 based on age, sex, and extraabdominal AIS. Injury patterns and in-hospital outcomes were compared. Initial operative management strategies, including selective nonoperative management (SNOM) for isolated solid organ injuries, were also compared. RESULTS: Of the 6435 patients with isolated abdominal GSW, 183 (3%) MIL were identified and matched with 549 CIV patients. The MIL group had more hollow viscus injuries (84% vs. 66%) while the CIV group had more vascular injuries (10% vs. 21%) (p < .05 for both). Operative strategy differed, with more MIL patients undergoing exploratory laparotomy (95% vs. 82%) and colectomy (72% vs. 52%) (p < .05 for both). However, no difference in ostomy creation was appreciated. More SNOM for isolated solid organ injuries was performed in the CIV group (34.1% vs. 12.5%; p < 0.05). In-hospital outcomes, including mortality, were similar between groups. CONCLUSIONS: MIL abdominal GSW lead to higher rates of hollow viscus injuries compared to CIV GSW. MIL GSW are more frequently treated with resection but with similar ostomy creation compared to civilian GSW. SNOM of solid organ injuries is infrequently performed following MIL GSW.

Comparison of Survival among Colon Cancer Patients in the U.S. Military Health System and Patients in the Surveillance, Epidemiology, and End Results (SEER) Program.

BACKGROUND: Access to health care is associated with cancer survival. The U.S. military health system (MHS) provides universal health care to beneficiaries, reducing barriers to medical care access. However, it is unknown whether the universal care has translated into improved survival among patients with colon cancer. We compared survival of patients with colon cancer in the MHS to that in the U.S. general population and assessed whether stage at diagnosis differed between the two populations and thus could contribute to survival difference. METHODS: The data were from Department of Defense's (DoD) Automated Central Tumor Registry (ACTUR) and the NCI's Surveillance, Epidemiology, and End Results (SEER) program, respectively. The ACTUR (N = 11,907) and SEER patients (N = 23,814) were matched to demographics and diagnosis year with a matching ratio of 1:2. Multivariable Cox regression model was used to estimate all-cause mortality for ACTUR compared with SEER. RESULTS: ACTUR patients exhibited better survival than their SEER counterparts (HR, 0.82; 95% confidence interval, 0.79-0.87) overall and in most subgroups by age, in both men and women, and in whites and blacks. The better survival remained when the comparison was stratified by tumor stage. CONCLUSIONS: Patients with colon cancer in a universal health care system had better survival than patients in the general population. IMPACT: Universal care access is important to improve survival of patients with colon cancer.

USA Department of Defense audit of surgical antibiotic prophylaxis prescribing patterns in inguinal hernia repair.

PURPOSE: Antibiotic prophylaxis in inguinal hernia repair (IHR) is contentious in literature and practice. In low-risk patients, for whom evidence suggests antibiotic prophylaxis is unnecessary, many surgeons still advocate for its routine use. This study surveys prescription patterns of Department of Defense (DoD) general surgeons. METHODS: An anonymous survey was sent electronically to approximately 350 DoD general surgeons. The survey asked multiple-choice and free text answers about prescribing patterns and knowledge of current evidence for low-risk patients undergoing elective open inguinal hernia repair without mesh (OIHRWOM), open inguinal hernia repair with mesh (OIHRWM), or laparoscopic inguinal hernia repair (LIHR). RESULTS: 110 DoD general surgeons consented to participate. 58.6, 95 and 84.2% of surgeons always administer antibiotic prophylaxis in OIHRWOM, OIHRWM, and LIHR, respectively. 37.9, 70.9, and 63.2% of surgeons believe that it reduces rates of surgical site infection in OIHRWOM, OIHRWM, and LIHR, respectively. The most common reasons for empirically prescribing antibiotic prophylaxis include "I think the evidence supports it" (27 of 72 responses), "I would rather be conservative and safe" (15 of 72 responses), and "I am following my hospital/department guidelines" (9 of 72 responses). 11.8, 40.8, and 32.9% of surgeons believe current evidence supports antibiotic prophylaxis use in OIHRWM, OIHRWOM, and LIHR, respectively. 50, 18.4, and 22.4% of surgeons believe current evidence refutes antibiotic prophylaxis use in OIHRWM, OIHRWOM, and LIHR, respectively. CONCLUSION: The survey results indicate that the majority of practicing DoD general surgeons still empirically prescribe surgical antibiotic prophylaxis in IHR despite more conflicting opinions that it has no meaningful effect or that current evidence does not supports its use.

Shock Index as a Predictor of Massive Transfusion and Emergency Surgery on the Modern Battlefield.

BACKGROUND: Shock Index (SI) has been used to predict the need for massive transfusion (MT) and emergency surgical procedures (ESP) in civilian trauma. We hypothesize that SI can reliably identify combat trauma patients that will require MT and ESP when applied to the resource-constrained, combat environment. METHODS: A retrospective review was performed within the Department of Defense Trauma Registry (2008-2016). SI was calculated using heart rate and systolic blood pressure on arrival to the initial facility with surgical capabilities. A threshold value of 0.8 was used to stratify patients into two groups (Group I, SI < 0.8; and Group II, SI ≥ 0.8). The need for MT, ESP, and mortality was compared. Regression analyses were conducted to determine the independent association of SI with MT and ESP. RESULTS: A total of 4008 patients were included. The mean age of the patients was 25.5 y, and the majority were predominately male (98%). Mechanisms of injury were blunt and blast injury (62%), penetrating injury (36.7%), and burn injury (0.5%). Overall, 77% of patients (n = 3070) were stratified to Group I, and 23% of patients (n = 938) were stratified to Group II, by SI. Group II patients had a significantly greater need for MT (8.4% versus 0.4%) and ESP (30.7% versus 6.5%), both P < 0.001. Regression analysis controlling for age, gender, Injury Severity Score, and Glasgow Coma Score confirmed that SI ≥ 0.8 was an independent risk factor for both MT and need for ESPs (P < 0.001). CONCLUSIONS: SI is a significant predictor of the need for MT and ESPs in the military trauma population, representing a simple and potentially potent tool for triage and prediction of resource consumption in the resource-limited, austere setting.

Early outcomes following trauma related to sex: A matched analysis of military service members in the department of defense trauma registry.

BACKGROUND: Several studies have identified sex as a factor influencing early outcomes after trauma. With the increased representation of women in combat roles, there is a need for improved understanding of the pathophysiology of traumatic injury in women. The purpose of this study was to define sex-based differences in early combat trauma outcomes amongst military service members. METHODS: A retrospective review of the Department of Defense Trauma Registry between 2008 and 2016 was performed. A 2:1 case control match was performed to match for Injury Severity Score, mechanism of injury, and age. The primary outcome of the study was mortality. RESULTS: A total of 4,625 patients were included in the study, 2.2% of whom were women. Women were less significantly injured than men (Injury Severity Score, 7.7 vs. 11, p = 0.003) and more likely to sustain blunt trauma (81% vs. 62.5%, p = 0.01). After case-control matching, 202 men and 101 women were evaluated. There was no statistical difference in the primary outcome of mortality. There was no statistical difference in Glasgow Coma Scale score, crystalloid or colloid administration, Packed Red Blood Cells (PRBC), platelet, cryoprecipitate, or plasma usage between men and women. CONCLUSION: Contrary to the civilian trauma literature, our study demonstrated no significant difference in early mortality between male and female combat casualties in a matched cohort. This finding may represent a difference in injury patterns, resuscitation practices, or lifesaving interventions in a deployed setting as compared with civilian setting. As the proportion of women involved in combat operations continues to increase, prospective studies should be performed to better define injury patterns, as well as early and late outcomes related to military trauma in the female population. LEVEL OF EVIDENCE: Retrospective, Level IV.

Racial Differences in Extremity Soft Tissue Sarcoma Treatment in a Universally Insured Population.

BACKGROUND: In prior reports from population-based databases, black patients with extremity soft tissue sarcoma (ESTS) have lower reported rates of limb-sparing surgery and adjuvant treatment. The objective of this study was to compare the multimodality treatment of ESTS between black and white patients within a universally insured and equal-access health care system. METHODS: Claims data from TRICARE, the US Department of Defense insurance plan that provides health care coverage for 9 million active-duty personnel, retirees, and dependents, were queried for patients younger than 65 y with ESTS who underwent limb-sparing surgery or amputation between 2006 and 2014 and identified as black or white race. Multivariable logistic regression analysis was used to evaluate the impact of race on the utilization of surgery, chemotherapy, and radiation. RESULTS: Of the 719 patients included for analysis, 605 patients (84%) were white and 114 (16%) were black. Compared with whites, blacks had the same likelihood of receiving limb-sparing surgery (odds ratio [OR], 0.861; 95% confidence interval [95% CI], 0.284-2.611; P = 0.79), neoadjuvant radiation (OR, 1.177; 95% CI, 0.204-1.319; P = 0.34), and neoadjuvant (OR, 0.852; 95% CI, 0.554-1.311; P = 0.47) and adjuvant (OR, 1.211; 95% CI, 0.911-1.611; P = 0.19) chemotherapy; blacks more likely to receive adjuvant radiation (OR, 1.917; 95% CI, 1.162-3.162; P = 0.011). CONCLUSIONS: In a universally insured population, racial differences in the rates of limb-sparing surgery for ESTS are significantly mitigated compared with prior reports. Biologic or disease factors that could not be accounted for in this study may contribute to the increased use of adjuvant radiation among black patients.

Mortality review of US Special Operations Command battle-injured fatalities.

BACKGROUND: Comprehensive analyses of battle-injured fatalities, incorporating a multidisciplinary process with a standardized lexicon, is necessary to elucidate opportunities for improvement (OFIs) to increase survivability. METHODS: A mortality review was conducted on United States Special Operations Command battle-injured fatalities who died from September 11, 2001, to September 10, 2018. Fatalities were analyzed by demographics, operational posture, mechanism of injury, cause of death, mechanism of death (MOD), classification of death, and injury severity. Injury survivability was determined by a subject matter expert panel and compared with injury patterns among Department of Defense Trauma Registry survivors. Death preventability and OFI were determined for fatalities with potentially survivable or survivable (PS-S) injuries using tactical data and documented medical interventions. RESULTS: Of 369 United States Special Operations Command battle-injured fatalities (median age, 29 years; male, 98.6%), most were killed in action (89.4%) and more than half died from injuries sustained during mounted operations (52.3%). The cause of death was blast injury (45.0%), gunshot wound (39.8%), and multiple/blunt force injury (15.2%). The leading MOD was catastrophic tissue destruction (73.7%). Most fatalities sustained nonsurvivable injuries (74.3%). For fatalities with PS-S injuries, most had hemorrhage as a component of MOD (88.4%); however, the MOD was multifactorial in the majority of these fatalities (58.9%). Only 5.4% of all fatalities and 21.1% of fatalities with PS-S injuries had comparable injury patterns among survivors. Accounting for tactical situation, a minority of deaths were potentially preventable (5.7%) and a few preventable (1.1%). Time to surgery (93.7%) and prehospital blood transfusion (89.5%) were the leading OFI for PS-S fatalities. Most fatalities with PS-S injuries requiring blood (83.5%) also had an additional prehospital OFI. CONCLUSION: Comprehensive mortality reviews of battlefield fatalities can identify OFI in combat casualty care and prevention. Standardized lexicon is essential for translation to civilian trauma systems. LEVEL OF EVIDENCE: Epidemiological, level IV.

High crystalloid volumes negate benefit of hemostatic resuscitation in pediatric wartime trauma casualties.

BACKGROUND: Recent data for adult trauma patients suggest improved survival when using hemostatic resuscitation, which includes limiting crystalloids and using closer to 1:1 ratios for both fresh frozen plasma (FFP) and platelets (PLTs) relative to packed red blood cells (PRBCs). Pediatric studies have shown similar but mixed results and often lack measuring crystalloids. We seek to evaluate in-hospital survival based on crystalloid administration and different blood product ratios in pediatric casualties during the recent conflicts. METHODS: We queried the Department of Defense Trauma Registry for all pediatric encounters in Iraq and Afghanistan from January 2007 to January 2016 and included those with at least 40 mL/kg of total blood products administered provided that they received at least 1 U of PRBC. We grouped children as younger (0-7 years) and older (8-17 years). We grouped low versus high ratios for FFP/PRBC (≤1:2 vs. >1:2) and PLT/PRBC (≤1:6 vs. >1.6). We used a threshold of 40 mL/kg to for high versus low crystalloid resuscitation. RESULTS: During this time, there were 3,439 encounters in the registry with 521 (15.1%) that met the inclusion criteria. The median age of casualties that met the inclusion was 10 years (interquartile range, 5-13), most were male (73.5%), with a moderate median injury severity score (17; interquartile range, 13-25). We performed regression modeling with adjustments for mechanism of injury, composite injury severity score, and total blood product volume (mL/kg based), grouping children based on high versus low fluid resuscitation. In the low-volume crystalloid group, we found that higher (>1:2) FFP/PRBC was associated with improved survival (odds ratio [OR], 3.42). However, in the high fluid crystalloid resuscitation group, we found that that higher ratios for PLT/PRBC (>1:6) overall (OR, 0.46) and the FFP/PRBC (>1:2) in younger children (OR, 0.28) was associated with worse survival. The remaining associations were not statistically significant. CONCLUSION: We found an association with survival in massively transfused pediatric trauma patients who received both a high FFP/PRBC ratio and low crystalloid administration. The benefit of this high ratio is negated, in patients receiving high crystalloid volumes, particularly among smaller children. Future studies on hemostatic resuscitation evaluating blood product ratios should also account for crystalloid and colloid administration. LEVEL OF EVIDENCE: Retrospective, comparative, level III.

Status of Robotic-Assisted Surgery (RAS) in the Department of Defense (DoD).

INTRODUCTION: Since inception of robotic-assisted surgery (RAS) in 1999, there has been an exponential rise in RAS in both number and complexity of surgical cases performed. The majority of these cases are gynecologic surgery in nature, with only a quarter of them labeled as general surgery. The purpose of this study is to determine if RAS in the Department of Defense (DoD) mirrors these trends. METHODS: A total of 6,204 RAS cases from across the DoD were reviewed between 01 January 2015 and 30 September 2017 from every Military Treatment Facility (MTF) that employs a robotic surgical device (various models of the da Vinci robotic surgical system by Intuitive Surgical). Specialty, number, and surgeon were recorded for each case. These end points were also examined for trends overtime and compared to similar civilian data. RESULTS: The number of MTFs performing robotic surgery and the number of cases performed increased significantly. An average of 373 cases per quarter-year were performed in 2015, 647 in 2016, and 708 in 2017. The number of RAS cases increased by about 10% every quarter-year during this time period. RAS was most commonly performed by general surgery in 10 of the 14 MTFs examined. CONCLUSIONS: MTFs implemented RAS much later than the civilian world. However, since its implementation, the frequency of RAS use has increased at a faster rate in the DoD than in the civilian world. Possible reasons for this are a younger pool of surgeons in the military and less demands on cost-effective productivity, allowing these younger surgeons to focus on emerging technology rather than maximizing surgical cost efficiency. General surgery constitutes the majority of RAS cases in the DoD. It is unclear why this difference from the civilian world exists.

The Optimal Length of Stay Associated With the Lowest Readmission Risk Following Surgery.

BACKGROUND: Index length of stay (LOS) and readmissions are viewed as important quality measures. However, these metrics represent competing demands as an inordinate reduction in LOS may lead to unplanned readmissions. We sought to assess the optimal LOS associated with the lowest 90-d readmission rate following discharge after common surgical procedures. MATERIALS AND METHODS: This was a retrospective study relying on Tricare claims. We identified all eligible adult patients (18-64 y) receiving a series of common surgical procedures between 2006 and 2014. We used a generalized additive model with spline regression to determine the optimal LOS associated with the lowest 90-d risk of readmission. RESULTS: Ninety-day readmission rates varied from 6.03% to 34.69%. Most procedures exhibited a logit linear relationship, with the lowest risk of readmission evident on postoperative day-1 and increasing thereafter. Among the more invasive procedures (e.g., esophagectomy and radical cystectomy), a U-shaped relationship was realized, indicating that expedited discharge would increase the potential for readmission as would any extended hospital LOS. For these procedures, the ideal index LOS appeared to be 6-7 d for radical cystectomy and 12-13 d for esophagectomy. CONCLUSIONS: Our results support the practice of discharging patients as soon as clinically feasible after hip and knee arthroplasty, lumbar spine surgery, hernia repair, appendectomy, nephrectomy, and colectomy. Among esophagectomy or radical cystectomy, there is a well-defined optimal index admission period and discharge outside this window appears to be detrimental. Our results suggest that invasive procedures appear to possess a unique "signature" when it comes to optimal LOS.

Neurosurgical workload during US combat operations: 2002 to 2016.

BACKGROUND: Approximately 4.5% of surgical procedures performed at Role 2 (R2) (forward surgical) and Role 3 (R3) (theater) medical treatment facilities can be classified as neurosurgical. These procedures are foreign to the routine daily practice of the military general surgeon. The purpose of this study was to examine the neurosurgical workload in Iraq and Afghanistan in order to inform the future predeployment neurosurgical training needs of nonneurosurgical providers. METHODS: Retrospective analysis of the Department of Defense Trauma Registry for all R2 and R3 medical facilities, from January 2002 to May 2016. The 103 neurosurgical International Classification of Diseases, Ninth Revision, Clinical Modification procedure codes identified were grouped by anatomic location. Select groups were further subdivided. Data analysis used Stata version 14 (College Station, TX). RESULTS: A total of 7,509 neurosurgical procedures were identified. The majority (7,244 [96.5%]) occurred at R3 theater hospitals. Cranial procedures were the most common at both R2 (120, 45.3%) and R3 (4,483 [61.9%]), with craniotomy/craniectomy the most frequent procedure. Spine procedures were performed almost exclusively at R3, with 61.1% being fusions/stabilizations and 26.9% being spinal decompression alone. Neurosurgical caseload was variable over the 15-year study period, dropping to almost zero in 2016. CONCLUSIONS: Neurosurgical procedures were performed primarily at larger R3 theater hospitals where neurosurgeons were assigned if present in theater; however, more than 100 cranial procedures were performed at forward R2 where neurosurgeons were not deployed. Considering that neurosurgeons are not everywhere available within the war zone, deploying general surgeons should have familiarity with trauma neurosurgery. LEVEL OF EVIDENCE: Epidemiologic study, level III; Care Management, level IV.

Evaluating the Effect of Treatment Persistence on the Economic Burden of Moderate to Severe Psoriasis and/or Psoriatic Arthritis Patients in the U.S. Department of Defense Population.

BACKGROUND: Psoriasis is a chronic, hyper-proliferative dermatological condition associated with joint symptoms known as psoriatic arthritis (PsA). In a 2013 review, the total economic burden of PsA was estimated at $51.7-$63.2 billion. The economic burden of moderate to severe psoriasis patients has reduced significantly with the advent of biologics, but there remains a dearth of real-world evidence of the impact of treatment persistence on the economic burden of moderate to severe psoriasis and/or PsA patients. OBJECTIVE: To evaluate the overall and psoriasis and/or PsA-related health care utilization and costs among patients who were persistent versus those nonpersistent on index biologic among the moderate to severe psoriasis and/or PsA population. METHODS: Adult patients with ≥ 2 claims with diagnosis of psoriasis and/or PsA during the period of November 2010-October 2015 were identified from the U.S. Department of Defense database; the first diagnosis date during November 2011-October 2014 was defined as the index date. As of the index date, patients were considered to have moderate to severe psoriasis or PsA if they had ≥ 1 nontopical systemic therapy or phototherapy during the 1-year pre- or 1-month post-index date. Persistence to index therapy, defined as the first biologic used (etanercept, adalimumab, ustekinumab, infliximab) on or within 30 days post-index date, was determined based on the biologic dosing schedule and a 90-day gap. Generalized linear models were used to compare the health care utilization and costs between persistent and nonpersistent patients during the 1-year post-index period. RESULTS: A total of 2,945 moderate to severe psoriasis and/or PsA patients were identified. Of those, 1,899 (64.5%) were persistent and 1,046 (35.5%) were nonpersistent. Compared with nonpersistent patients, persistent patients were older (49.2 vs. 45.5 years; P < 0.001) and more likely to be male (52% vs. 45%; P < 0.001). More persistent patients were diagnosed with dyslipidemia (40% vs. 35%; P = 0.002), had lower antidepressant use (23.4% vs. 27.4%; P < 0.001), and had lower anxiolytic use (30% vs. 37%; P < 0.001) compared with nonpersistent patients. After adjusting for demographic and clinical characteristics, nonpersistent patients had higher total medical costs ($12,457 vs. $8,964; P < 0.001) compared with persistent patients, and ambulatory visits (23.9 vs. 21.4; P = 0.007) were a major contributor. Approximately 40% of the total overall medical costs were attributed to psoriasis and PsA. Although persistent patients incurred higher pharmacy costs ($10,684 vs. $7,849; P < 0.001) due to higher biologic use and the potentially high per-unit cost of biologics, their psoriasis- and/or PsA-related medical costs were significantly lower than those of nonpersistent patients ($3,395 vs. $5,041; P < 0.001). Total overall costs combining medical and pharmacy costs were similar between the cohorts ($22,678 vs. $21,477; P = 0.122). CONCLUSIONS: Moderate to severe psoriasis and/or PsA patients who were persistent on index biologic treatment had higher pharmacy utilization and costs, albeit with lower medical costs and similar total costs, compared with nonpersistent patients. DISCLOSURES: This study was funded by Janssen Scientific Affairs. Lee is a paid employee of Janssen Scientific Affairs. Xie, Wang, Vaidya, and Baser are paid employees of STATinMED Research, which is a paid consultant to Janssen Scientific Affairs. This study was presented as an abstract at the Academy of Managed Care Pharmacy 2017 Annual Meeting, March 27-30, 2017, in Denver, CO.

Contemporary Factors Associated with the Use of Laparoscopy for Inguinal Hernia Repair Among Department of Defense Beneficiaries.

INTRODUCTION: The factors that contribute to variation in utilization of laparoscopic inguinal hernia repair are unknown. We sought to determine the current usage patterns of laparoscopic and open surgery in the elective repair of uncomplicated unilateral inguinal hernia in a large population with universal health care coverage comprised of Department of Defense (DoD) beneficiaries. MATERIALS AND METHODS: The DoD Military Health System Data Repository (MDR) tracks health care delivered to a universally insured population of active/reserve/retired members of the U.S. Armed Services and their dependents. The MDR was queried for elective unilateral inguinal hernia repair among adult patients between 2008 and 2014. The primary outcome was laparoscopic (vs. open) approach to hernia repair. We conducted univariable and multivariable analyses of patient- and systems-level factors associated with approach to inguinal hernia repair. This research was approved by our institutional review board prior to commencement of the study and need for informed consent was waived given the design of this study. RESULTS: Among 37,742 elective uncomplicated unilateral inguinal hernia repairs, 35% (n = 13,114) were performed laparoscopically. In 2014, 40% of inguinal hernia repairs were performed laparoscopically, compared with 27% of repairs in 2008 (P < 0.01). In multivariable analysis, laparoscopic hernia repair was more likely for male patients (OR = 1.38, 95% CI = 1.23-1.54, P < 0.01), military (vs. civilian) institutions (OR = 1.34, 95% CI = 1.28-1.41, P < 0.01), active-duty officers (vs. active-duty enlisted; OR = 1.21, 95% CI = 1.12-1.30, P < 0.01), and more recent year of surgery (P < 0.01). Laparoscopic repair was significantly less likely among patients with greater than one comorbidity (vs. none; OR = 0.68, 95% CI = 0.61-0.76, P < 0.01). CONCLUSION: In a large, universally insured population of military service members and their dependents, laparoscopic inguinal repair is increasingly used and was preferred over open repair for younger, healthier, active-duty patients and those treated within the military (vs. non-military) care system.

Past and present role of extracorporeal membrane oxygenation in combat casualty care: How far will we go?

Advanced extracorporeal therapies have been successfully applied in the austere environment of combat casualty care over the previous decade. In this review, we describe the historic underpinnings of extracorporeal membrane oxygenation, review the recent experience with both partial and full lung support during combat operations, and critically assess both the current status of the Department of Defense extracorporeal membrane oxygenation program and the way forward to establish long-range lung rescue therapy as a routine capability for combat casualty care.

Leveraging healthcare utilization to explore outcomes from musculoskeletal disorders: methodology for defining relevant variables from a health services data repository.

BACKGROUND: Large healthcare databases, with their ability to collect many variables from daily medical practice, greatly enable health services research. These longitudinal databases provide large cohorts and longitudinal time frames, allowing for highly pragmatic assessment of healthcare delivery. The purpose of this paper is to discuss the methodology related to the use of the United States Military Health System Data Repository (MDR) for longitudinal assessment of musculoskeletal clinical outcomes, as well as address challenges of using this data for outcomes research. METHODS: The Military Health System manages care for approximately 10 million beneficiaries worldwide. Multiple data sources pour into the MDR from multiple levels of care (inpatient, outpatient, military or civilian facility, combat theater, etc.) at the individual patient level. To provide meaningful and descriptive coding for longitudinal analysis, specific coding for timing and type of care, procedures, medications, and provider type must be performed. Assumptions often made in clinical trials do not apply to these cohorts, requiring additional steps in data preparation to reduce risk of bias. The MDR has a robust system in place to validate the quality and accuracy of its data, reducing risk of analytic error. Details for making this data suitable for analysis of longitudinal orthopaedic outcomes are provided. RESULTS: Although some limitations exist, proper preparation and understanding of the data can limit bias, and allow for robust and meaningful analyses. There is the potential for strong precision, as well as the ability to collect a wide range of variables in very large groups of patients otherwise not captured in traditional clinical trials. This approach contributes to the improved understanding of the accessibility, quality, and cost of care for those with orthopaedic conditions. CONCLUSION: The MDR provides a robust pool of longitudinal healthcare data at the person-level. The benefits of using the MDR database appear to outweigh the limitations.