A guide to interpreting systematic reviews and meta-analyses in neurosurgery and surgery.

INTRODUCTION: Systematic reviews (SRs) and meta-analyses (MAs) are methods of data analysis used to synthesize information presented in multiple publications on the same topic. A thorough understanding of the steps involved in conducting this type of research and approaches to data analysis is critical for appropriate understanding, interpretation, and application of the findings of these reviews. METHODS: We reviewed reference texts in clinical neuroepidemiology, neurostatistics and research methods and other previously related articles on meta-analyses (MAs) in surgery. Based on existing theories and models and our cumulative years of expertise in conducting MAs, we have synthesized and presented a detailed pragmatic approach to interpreting MAs in Neurosurgery. RESULTS: Herein we have briefly defined SRs sand MAs and related terminologies, succinctly outlined the essential steps to conduct and critically appraise SRs and MAs. A practical approach to interpreting MAs for neurosurgeons is described in details. Based on summary outcome measures, we have used hypothetical examples to illustrate the Interpretation of the three commonest types of MAs in neurosurgery: MAs of Binary Outcome Measures (Pairwise MAs), MAs of proportions and MAs of Continuous Variables. Furthermore, we have elucidated on the concepts of heterogeneity, modeling, certainty, and bias essential for the robust and transparent interpretation of MAs. The basics for the Interpretation of Forest plots, the preferred graphical display of data in MAs are summarized. Additionally, a condensation of the assessment of the overall quality of methodology and reporting of MA and the applicability of evidence to patient care is presented. CONCLUSION: There is a paucity of pragmatic guides to appraise MAs for surgeons who are non-statisticians. This article serves as a detailed guide for the interpretation of systematic reviews and meta-analyses with examples of applications for clinical neurosurgeons.

Global Neurosurgery: Progress and Resolutions at the 75th World Health Assembly.

Neurosurgical advocates for global surgery/neurosurgery at the 75th World Health Assembly gathered in person for the first time after the COVID-19 pandemic in Geneva, Switzerland, in May 2022. This article reviews the significant progress in the global health landscape targeting neglected neurosurgical patients, emphasizing high-level policy advocacy and international efforts to support a new World Health Assembly resolution in mandatory folic acid fortification to prevent neural tube defects. The process of developing global resolutions through the World Health Organization and its member states is summarized. Two new global initiatives focused on the surgical patients among the most vulnerable member states are discussed, the Global Surgery Foundation and the Global Action Plan on Epilepsy and other Neurological Disorders. Progress toward a neurosurgery-inspired resolution on mandatory folic acid fortification to prevent spina bifida-folate is described. In addition, priorities for moving the global health agenda forward for the neurosurgical patient as it relates to the global burden of neurological disease are reviewed after the COVID-19 pandemic.

Current Neurosurgical Care in Ethiopia Using the Lens of the Lancet Global Health Commission on High-Quality Health Systems.

BACKGROUND: Neurosurgery is a rapidly developing specialty in Ethiopia. Previous global neurosurgery studies have highlighted the need for synchronizing workforce increase with improving quality, access, and capacity to provide neurosurgical care. OBJECTIVE: To evaluate Ethiopia's neurosurgical system and highlight the critical interventions required for the sustained development of Ethiopian neurosurgery as part of a high-quality health system (HQHS). METHODS: A comprehensive survey was sent to all practicing neurosurgeons. Public databases on Ethiopian census reports and current road infrastructure were used for spatial analysis of neurosurgical access. RESULTS: The survey response rate was 90% (45/50). Most respondents were men (95.6%), aged 30 to 40 years (82%), who worked at national referral hospitals (71%). The reported annual caseload per practicing neurosurgeon was >150 cases for 40% of urban and 20% of rural neurosurgeons. Head and spine neurotrauma and tumors were the most common neurosurgical indications. Computed tomography scanner was the most widely available diagnostic equipment (62%). 76% of respondents indicated the presence of postoperative rehabilitation care at their institutions. Thirteen percent and 27% of the nation lived within a 2-hour and 4-hour driving distance from a neurosurgical center, respectively. CONCLUSION: The results highlight the need for vital improvements in neurosurgical capacity to sustain progress toward HQHS. Promoting sustained development in all components of HQHS can be achieved by diversifying the workforce and training residency candidates committed to practicing in underserved regions. Additional strategies might include establishing a national registry for neurosurgical data and implementing policy changes conducive to improving perihospital care and other health system components.

Future Directions for Global Clinical Neurosurgical Training: Challenges and Opportunities.

OBJECTIVE: Expanded access to training opportunities is necessary to address 5 million essential neurosurgical cases not performed annually, nearly all in low- and middle-income countries. To target this critical neurosurgical workforce issue and advance positive collaborations, a summit (Global Neurosurgery 2019: A Practical Symposium) was designed to assemble stakeholders in global neurosurgical clinical education to discuss innovative platforms for clinical neurosurgery fellowships. METHODS: The Global Neurosurgery Education Summit was held in November 2021, with 30 presentations from directors and trainees in existing global neurosurgical clinical fellowships. Presenters were selected based on chain referral sampling from suggestions made primarily from young neurosurgeons in low- and middle-income countries. Presentations focused on the perspectives of hosts, local champions, and trainees on clinical global neurosurgery fellowships and virtual learning resources. This conference sought to identify factors for success in overcoming barriers to improving access, equity, throughput, and quality of clinical global neurosurgery fellowships. A preconference survey was disseminated to attendees. RESULTS: Presentations included in-country training courses, twinning programs, provision of surgical laboratories and resources, existing virtual educational resources, and virtual teaching technologies, with reference to their applicability to hybrid training fellowships. Virtual learning resources developed during the coronavirus disease 2019 pandemic and high-fidelity surgical simulators were presented, some for the first time to this audience. CONCLUSIONS: The summit provided a forum for discussion of challenges and opportunities for developing a collaborative consortium capable of designing a pilot program for efficient, sustainable, accessible, and affordable clinical neurosurgery fellowship models for the future.

Racial and Ethnical Diversity Within the Neurosurgery Resident and Faculty Workforce in the United States.

BACKGROUND: Promoting workplace diversity leads to a variety of benefits related to a broader range of perspectives and insights. Underrepresented in medicine (URiM), including African Americans, Latinx, and Natives (Americans/Alaskan/Hawaiians/Pacific Islanders), are currently accounting for approximately 40% of the US population. OBJECTIVE: To establish a snapshot of current URiM representation within academic neurosurgery (NS) programs and trends within NS residency. METHODS: All 115 NS residencies and academic programs accredited by the Accreditation Council for Graduate Medical Education in 2020 were included in this study. The National Residency Matching Program database was reviewed from 2011 to 2020 to analyze URiM representation trends over time within the NS resident workforce. The academic rank, academic and clinical title(s), subspecialty, sex, and race of URiM NS faculty (NSF) were obtained from publicly available data. RESULTS: The Black and Latinx NS resident workforce currently accounts for 4.8% and 5.8% of the total workforce, respectively. URiM NSF are present in 71% of the Accreditation Council for Graduate Medical Education-accredited NS programs and account for 8% (148 of 1776) of the workforce. Black and Latinx women comprise 10% of URiM NSF. Latinx NSFs are the majority within the URiM cohort for both men and women. URiM comprise 5% of all department chairs. All are men. Spine (26%), tumor (26%), and trauma (17%) were the top 3 subspecialties among URiM NSF. CONCLUSION: NS has evolved, expanded, and diversified in numerous directions, including race and gender representation. Our data show that ample opportunities remain to improve URiM representation within NS.

Barriers to neurotrauma care in low- to middle-income countries: an international survey of neurotrauma providers.

OBJECTIVE: Delays along the neurosurgical care continuum are associated with poor outcomes and are significantly greater in low- to middle-income countries (LMICs), with timely access to neurotrauma care remaining one of the most significant unmet neurosurgical needs worldwide. Using Lancet Global Surgery metrics and the Three Delays framework, the authors of this study aimed to identify and characterize the most significant barriers to the delivery of neurotrauma care in LMICs from the perspective of local neurotrauma providers. METHODS: The authors conducted a cross-sectional study through the dissemination of a web-based survey to neurotrauma providers across all World Health Organization geographic regions. Responses were analyzed with descriptive statistics and Kruskal-Wallis testing, using World Bank data to provide estimates of populations at risk. RESULTS: Eighty-two (36.9%) of 222 neurosurgeons representing 47 countries participated in the survey. It was estimated that 3.9 billion people lack access to neurotrauma care within 2 hours. Nearly 3.4 billion were estimated to be at risk for impoverishing expenditure and 2.9 billion were at risk of catastrophic expenditure as a result of paying for care for neurotrauma injuries. Delays in seeking care were rated as slightly common (p < 0.001), those in reaching care were very common (p < 0.001), and those in receiving care were slightly common (p < 0.05). The most significant causes for delays were associated with reaching care, including geographic distance from a facility, lack of ambulance service, and lack of finances for travel. All three delays were correlated to income classification and geographic region. CONCLUSIONS: While expanding the global neurosurgical workforce is of the utmost importance, the study data suggested that it may not be entirely sufficient in gaining access to care for the emergent neurosurgical patient. Significant income and region-specific variability exists with regard to barriers to accessing neurotrauma care. Highlighting these barriers and quantifying worldwide access to neurotrauma care using metrics from the Lancet Commission on Global Surgery provides essential insight for future initiatives aiming to strengthen global neurotrauma systems.

The Current State of Neurosurgery in Somaliland.

BACKGROUND: Surgical conditions account for as much as one third of the global burden of disease, yet 5 billion people worldwide do not have access to timely, affordable surgical care. These disparities in access to timely surgical care are most pronounced in low- and middle-income countries, where the availability of specialty surgical services such as neurosurgery are severely limited or completely absent. The African autonomous region of Somaliland, in the Horn of Africa, is one such region. METHODS: Discussions were conducted with key individuals in Somaliland to ascertain the current state of neurosurgery in Somaliland. RESULTS: The current state of neurosurgery in Somaliland was characterized. First, a background on the recent history of the republic and the surrounding region was furnished, which provides context for the challenging socioeconomic conditions in Somaliland. Brief biographical sketches were presented of local leaders and general surgeons who are actively working to improve economic and health conditions and who welcome opportunities to improve all health services, including neurosurgery. In addition, an overview was presented of new initiatives in capacity building in neurosurgery and sources of directed training and care in neurosurgery. CONCLUSIONS: This article provides the first-ever assessment of current neurosurgery-related activity in Somaliland. The article provides recommendations to guide the international neurosurgery community in future contributions.

Neurosurgery in Ethiopia: A New Chapter and Future Prospects.

BACKGROUND: Inequitable access to surgical care is most conspicuous in low-income countries (LICs), such as Ethiopia, where infectious diseases, malnutrition, and other maladies consume the lion's share of the available health resources. The aim of this article was to provide an update on the current state of neurosurgery in Ethiopia and identify targets for future development of surgical capacity as a universal health coverage component in this East African nation. METHODS: Publicly available data included in this report were gathered from resources published by international organizations. A PubMed search was used for a preliminary bibliometric analysis of scholarly output of neurosurgeons in Ethiopia and other low-income countries. Statistical analysis was used to determine the correlation between the number of neurosurgeons and academic productivity. RESULTS: Neurosurgeon density has increased >20-fold from 0.0022 to 0.045 neurosurgeons per 100,000 population between 2006 and 2020. The increase in neurosurgeons was strongly correlated with an increase in total publications (P < 0.001) and the number of new publications per year (P = 0.003). Despite recent progress, the availability of neuroimaging equipment remains inadequate, with 38 computed tomography scanners and 11 magnetic resonance imaging machines for a population of 112.07 million. The geographic distribution of neurosurgical facilities is limited to 12 urban centers. CONCLUSIONS: Ethiopian neurosurgery exemplifies the profound effect of international partnerships for training local surgeons on progress in low-income countries toward improved neurosurgical capacity. Collaborations that focus on increasing the neurosurgical workforce should synchronize with efforts to enhance the availability of diagnostic and surgical equipment necessary for basic neurosurgical care.

Decentralization and Regionalization of Surgical Care: A Review of Evidence for the Optimal Distribution of Surgical Services in Low- and Middle-Income Countries.

BACKGROUND: While recommendations for the optimal distribution of surgical services in high-income countries (HICs) exist, it is unclear how these translate to resource-limited settings. Given the significant shortage and maldistribution of surgical workforce and infrastructure in many low- and middle-income countries (LMICs), the optimal role of decentralization versus regionalization (centralization) of surgical care is unknown. The aim of this study is to review evidence around interventions aimed at redistributing surgical services in LMICs, to guide recommendations for the ideal organization of surgical services. METHODS: A narrative-based literature review was conducted to answer this question. Studies published in English between 1997 and 2017 in PubMed, describing interventions to decentralize or regionalize a surgical procedure in a LMIC, were included. Procedures were selected using the Disease Control Priorities' (DCP3) Essential Surgery Package list. Intervention themes and outcomes were analyzed using a narrative, thematic synthesis approach. Primary outcomes included mortality, complications, and patient satisfaction. Secondary outcomes included input measures: workforce and infrastructure, and process measures: facility-based care, surgical volume, and referral rates. RESULTS: Thirty-five studies were included. Nine (33%) of the 27 studies describing decentralization showed an improvement in primary outcomes. The procedures associated with improved outcomes after decentralization included most obstetric, gynecological, and family planning services as well as some minor general surgery procedures. Out of 8 studies on regionalization (centralization), improved outcomes were shown for trauma care in one study and cataract extraction in one study. CONCLUSION: Interventions aimed at decentralizing obstetric care to the district hospital and health center levels have resulted in mortality benefits in several countries. However, more evidence is needed to link service distribution to patient outcomes in order to provide recommendations for the optimal organization of other surgical procedures in LMICs. Considerations for the optimal distribution of surgical procedures should include the acuity of the condition for which the procedure is indicated, anticipated case volume, and required level of technical skills, resources, and infrastructure. These attributes should be considered within the context of each country.

Injury-to-Admission Delay Beyond 4 Hours Is Associated with Worsening Outcomes for Traumatic Brain Injury in Cambodia.

BACKGROUND: In Cambodia, the most common victims of traumatic brain injury (TBI) are men 20-30 years of age involved in motor vehicle collision. Secondary injury sustained by these patients occurs during the time period between initial insult and hospital admission. Strengthening prehospital systems for TBI in low- and middle-income countries (LMICs) such as Cambodia is therefore a key element of the development agenda for universal health equity. We report a retrospective analysis of the relationship between prehospital delays and TBI outcomes among patients from a large government hospital in Cambodia. METHODS: Data were collected from 3476 patients with TBI admitted to a major government hospital in Phnom Penh, Cambodia, from June 2013 to June 2018. Patients with missing data or those admitted >8 hours postinjury were excluded. Statistical analyses examined associations between injury-to-admission delay (IAD) and outcomes such as Glasgow Outcome Scale (GOS) score and length of stay (LOS). RESULTS: A total of 2125 patients with TBI (76.85% men) were included. The median age was 27 years (interquartile range, 22-37 years). Injury severity at presentation included 1406 mild (66%), 464 moderate (22%), and 240 severe cases (11%). No Glasgow Coma Scale (GCS) data were available for 15 patients (1%). We found an inverse relationship between IAD and GOS score, most evidently for mild and moderate TBI (n = 1870; 88%). Regression analysis revealed a marked decrease in GOS score at the IAD >4-hour threshold. Each 30-minute delay in IAD was correlated with >2-hour increase in LOS for mild (P < 0.001) and moderate TBI (P < 0.001). CONCLUSIONS: In a retrospective cohort of >2000 patients with TBI from Cambodia, we found that increasing IAD was associated with worsening outcome, especially beyond the 4-hour threshold. These data should inform development of prehospital guidelines for TBI care in LMICs.

The Current State of Neurosurgery in Haiti.

BACKGROUND: Even though surgical conditions account for as much as 32% of the global burden of disease, 5 billion people worldwide do not have access to timely, affordable surgical and anesthetic care. Access to surgical care is separated along socioeconomic divides, and these disparities are most pronounced in low-and middle-income countries, such as the Caribbean nation of Haiti, where the availability of specialty surgical services like neurosurgery are scant, or completely absent. METHODS: This paper provides a narrative account of current neurosurgery-related activity in Haiti, a nation whose social, political, and economic context is unique in the Americas. RESULTS: After some background information and a bibliometric analysis of recent research efforts, we provide brief biographical sketches of Haiti's local neurosurgical leaders and an overview of recent initiatives in Haitian neurosurgical capacity building. CONCLUSIONS: The paper concludes with recommendations to guide the international neurosurgery community in future contributions.

Neurosurgery and Sustainable Development Goals.

BACKGROUND: On September 25, 2015, the United Nations General Assembly adopted a 17-goal action plan to transform the world by the year 2030, ushering in the Era of Sustainable Development. These Sustainable Development Goals (SDGs) were designed to continue where the preceding Millennium Development Goals left off, expanding on the Millennium Development Goal successes, and facing the challenges encountered during the previous decade and a half. The current Era of Sustainable Development and its impact on a breadth of neurosurgical concerns provide several unprecedented opportunities to enhance political prioritization of neurosurgical care equity. Neurosurgeons could therefore be well positioned to participate in the leadership of these global health development and policy reform efforts. METHODS: Each of the 17 SDGs was reviewed and analyzed for its relevance to the public health aspects of neurosurgery. The analysis was guided by a review of the literature performed in PubMed, Google Scholar, and the databases of the World Health Organization. RESULTS: Among the 17 SDGs, 14 were found to be of direct or indirect relevance to neurosurgeons and neurosurgical care delivery. Results of this analysis are presented and discussed, and recommendations are provided for using this knowledge to inform the emerging discipline of global neurosurgery. CONCLUSIONS: This article contributes to the global neurosurgery movement by providing the socially and globally conscious neurosurgeon with a compass for directing the place of neurosurgery in the international agenda for sustainable development.

Patterns of Hydrocephalus in Rural Haiti: A Computed Tomography-Based Study.

INTRODUCTION/OBJECTIVE: Hydrocephalus is a common neurosurgical disorder that can lead to significant disability or death if not promptly identified and treated. Data on the burden of hydrocephalus in low-income countries are limited, given a lack of radiologic resources for the diagnosis of this condition. Here, we present an analysis of patterns of hydrocephalus from a large sample of computed tomography (CT) scans of the head performed at a public hospital in rural Haiti, a low-income country in the Caribbean. METHODS: We analyzed reports from 3614 CT scans of the head performed between July 2013 and January 2016 for findings that were consistent with a diagnosis of hydrocephalus (report indicating "hydrocephalus," "ventriculomegaly," or "enlargement of the ventricles"). Extracted data included demographics, study indication, radiologic findings, and reported etiology of hydrocephalus. RESULTS: In total, 119 scans had findings concerning for hydrocephalus (3.5% of all scans, 6.3% of abnormal scans; age range 0-90 years; median age 35.5 years; 49.6% male). Pediatric patients (<18 years of age) accounted for 39% of cases. In total, 113 of 119 (95%) scans had indications for possible neurosurgical intervention. Among these 113 scans, 36 (30%) scans demonstrated communicating hydrocephalus, 66 (55%) scans demonstrated noncommunicating hydrocephalus (primarily due to intraventricular hemorrhage [27 scans, 23%] or brain tumors [24, 20%]), and 11 (9%) scans were indeterminate regarding whether the hydrocephalus was communicating versus noncommunicating. CONCLUSIONS: In a large sample of CTs performed in a rural low-income setting, hydrocephalus was common, predominantly noncommunicating, and often associated with potentially operable intracranial lesions. Data of this nature can inform research, policy, and clinical collaborations that strengthen the neurosurgical capacity of low-income countries.