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Background: The effects of hypoxia conditioning, which involves recurrent exposure to hypoxia combined with exercise training, on improving body composition in the ageing population have not been extensively investigated. Objective: This meta-analysis aimed to determine if hypoxia conditioning, compared to similar training near sea level, maximizes body composition benefits in middle-aged and older adults. Methods: A literature search of PubMed, EMBASE, Web of Science, Scopus and CNKI (China National Knowledge Infrastructure) databases (up to 27th November 2022) was performed, including the reference lists of relevant papers. Three independent reviewers extracted study characteristics and health outcome measures. Search results were limited to original studies of the effects of hypoxia conditioning on body composition in middle-aged and older adults. Results: Twelve studies with a total of 335 participants were included. Hypoxia conditioning induced greater reductions in body mass index (MD = -0.92, 95%CI: -1.28 to -0.55, I2 = 0%, p < 0.00001) and body fat (SMD = -0.38, 95%CI: -0.68 to -0.07, I2 = 49%, p = 0.01) in middle-aged and older adults compared with normoxic conditioning. Hypoxia conditioning improved lean mass with this effect not being larger than equivalent normoxic interventions in either middle-aged or older adults (SMD = 0.07, 95%CI -0.12 to 0.25, I2 = 0%, p = 0.48). Subgroup analysis showed that exercise in moderate hypoxia (FiO2 > 15%) had larger effects than more severe hypoxia (FiO2 ≤ 15%) for improving body mass index in middle-aged and older adults. Hypoxia exposure of at least 60 min per session resulted in larger benefits for both body mass index and body fat. Conclusion: Hypoxia conditioning, compared to equivalent training in normoxia, induced greater body fat and body mass index improvements in middle-aged and older adults. Adding hypoxia exposure to exercise interventions is a viable therapeutic solution to effectively manage body composition in ageing population. Key Points: A meta-analysis was conducted to evaluate the effects of hypoxia conditioning on body composition in middle-aged and older adults. Compared to normoxic equivalent, hypoxia conditioning provides greater reductions in body fat and body mass index. However, the magnitude of improvement in lean mass was not greater in hypoxic than normoxic conditions. Hypoxia conditioning of at least 60 minutes per session in moderate hypoxia (FiO2 > 15%) is a promising intervention to improve body composition in middle-aged and older adults. [ABSTRACT FROM AUTHOR]

Background: Compared with conventional top down costing, micro-costing may provide a more accurate method of resource-use assessment in economic analyses of surgical interventions, but little is known about its current use. The aim of this study was to systematically-review the use of micro-costing in surgery. Methods: Comprehensive searches identified complete papers, published in English reporting micro-costing of surgical interventions up to and including 22nd June 2018. Studies were critically appraised using a modified version of the Consensus on Health Economic Criteria (CHEC) Checklist. Study demographics and details of resources identified; methods for measuring and valuing identified resources and any cost-drivers identified in each study were summarised. Results: A total of 85 papers were identified. Included studies were mainly observational comparative studies (n = 42, 49.4%) with few conducted in the context of a randomised trial (n = 5, 5.9%). The majority of studies were single-centre (n = 66, 77.6%) and almost half (n = 40, 47.1%) collected data retrospectively. Only half (n = 46, 54.1%) self-identified as being 'micro-costing' studies. Rationale for the use of micro-costing was most commonly to compare procedures/techniques/processes but over a third were conducted specifically to accurately assess costs and/or identify cost-drivers. The most commonly included resources were personnel costs (n = 76, 89.4%); materials/disposables (n = 76, 89.4%) and operating-room costs (n = 62,72.9%). No single resource was included in all studies. Most studies (n = 72, 84.7%) identified key cost-drivers for their interventions. Conclusions: There is lack of consistency regarding the current use of micro-costing in surgery. Standardising terminology and focusing on identifying and accurately costing key cost-drivers may improve the quality and value of micro-costing in future studies. Trial registration: PROSPERO registration CRD42018099604. [ABSTRACT FROM AUTHOR]

Background: In order to close the gap between discoveries that could improve health, and widespread impact on routine health care practice, there is a need for greater attention to the factors that influence dissemination and implementation of evidence-based practices. Evidence synthesis projects (e.g., systematic reviews) could contribute to this effort by collecting and synthesizing data relevant to dissemination and implementation. Such an advance would facilitate the spread of high-value, effective, and sustainable interventions.Objective: The objective of this paper is to evaluate the feasibility of extracting factors related to implementation during evidence synthesis in order to enhance the replicability of successes of studies of interventions in health care settings.Design: Drawing on the implementation science literature, we suggest 10 established implementation measures that should be considered when conducting evidence synthesis projects. We describe opportunities to assess these constructs in current literature and illustrate these methods through an example of a systematic review.Subjects: Twenty-nine studies of interventions aimed at improving clinician-patient communication in clinical settings.Key Results: We identified acceptability, adoption, appropriateness, feasibility, fidelity, implementation cost, intervention complexity, penetration, reach, and sustainability as factors that are feasible and appropriate to extract during an evidence synthesis project.Conclusions: To fully understand the potential value of a health care innovation, it is important to consider not only its effectiveness, but also the process, demands, and resource requirements involved in downstream implementation. While there is variation in the degree to which intervention studies currently report implementation factors, there is a growing demand for this information. Abstracting information about these factors may enhance the value of systematic reviews and other evidence synthesis efforts, improving the dissemination and adoption of interventions that are effective, feasible, and sustainable across different contexts. [ABSTRACT FROM AUTHOR]

Global initiatives have raised awareness of the need for cross-departmental and cross-sectoral activities to support urban health, sustainability, and equity, with respective indicators routinely used as a way to catalyze and monitor action toward pre-defined goals. Despite the existence of at least 145 urban health indicator (UHI) tools globally, there has been very little research on the use of indicators by policy- and decision-makers; more attention has been devoted to their development and validation. This paper describes the second part of a two-part systematic review of the characteristics (part A) and use (part B, this part) of UHI tools by municipal built environment policy- and decision-makers. Part B is a narrative synthesis of studies on the use of UHI tools. This PRISMA-P compliant review follows a mixed methods sequential explanatory design. The search was conducted using seven bibliographic databases, grey literature searches, and key journal hand searches. Ten studies describing the use of ten UHI tools in seven countries were included in the narrative synthesis, resulting in development of a theory of change (ToC). We found that both expert-led and participatory indicator projects can be underpinned by research evidence and residents' knowledge. Our findings contradict the dominant view of indicator use in policy-making as a linear process, highlighting a number of technical, organizational, political, knowledge, and contextual factors that affect their use. Participatory UHI tools with community involvement were generally more effective at supporting "health in all policies" and "whole-of-society" approaches to governing healthy cities than expert-led processes. UHI tool producers proposed a range of techniques to address urban health complexity characteristics. Finally, in combining data from both parts of the review, we found that potentially important UHI tool features, such as neighbourhood-scale data, were influential in the use of indicators by built environment policy- and decision-makers. [ABSTRACT FROM AUTHOR]

Over the past three decades, a variety of meta-reasoning systems which support reasoning about higher-order abstract specifications have been designed and developed. In this paper, we survey and compare four meta-reasoning systems, Twelf, Beluga, Abella and Hybrid, using several benchmarks from the open repository ORBI that describes challenge problems for reasoning with higher-order abstract syntax representations. In particular, we investigate how these systems mechanize and support reasoning using a context of assumptions. This highlights commonalities and differences in these systems and is a first step towards translating between them. [ABSTRACT FROM AUTHOR]

Case studies are largely used for investigating software engineering practices. They are characterized by their flexible nature, multiple forms of data collection, and are mostly informed by qualitative data. Synthesis of case studies is necessary to build a body of knowledge from individual cases. There are many methods for such synthesis, but they are yet not well explored in software engineering. The objective of this research is to demonstrate the similarities and differences of the results and conclusions when applying three different methods of synthesis, and to discuss the challenges of synthesizing evidence from reported case studies in SE. We describe a worked example of three such methods where three independent teams synthesized two studies that investigated critical factors of trust in outsourced projects through thematic synthesis and cross-case analysis, and compared these to each other and also to an already published narrative synthesis. In addition, despite that the primary studies were well presented for synthesis, we identified challenges in the use of case studies synthesis methods related to the goals and research questions of the synthesis, the types and number of case studies, variations in context, limited access to raw data, and quality of the case studies. Thus, we recommend that the analysts should be aware of these challenges and try to account for them during the execution of the synthesis. We also recommend that analysts consider using more than one method of synthesis for sake of reliability of the results and conclusions. [ABSTRACT FROM AUTHOR]

Background: This study aims to assess the rate at which screening colonoscopy is performed on patients younger or older than the age range specified in national guidelines, or at shorter intervals than recommended. Such non-indicated use of the procedure is considered low-value care, or overuse. This study is the first systematic review of the rate of non-indicated completed screening colonoscopy in the USA.Methods: PubMed and Embase were queried for relevant studies on overuse of screening colonoscopy published from January 1, 2002, until January 23, 2019. English-language studies that were conducted for screening colonoscopy after 2001 for average-risk patients were included. Studies must have followed national guidelines for detecting rates of overuse. We followed methods outlined in the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) and the reporting recommendations of the Meta-analysis of Observational Studies in Epidemiology group (MOOSE).Results: A total of 772 papers were reviewed for inclusion; 42 were reviewed in full text. Of those reviewed, six studies met eligibility criteria, including a total of 459,503 colonoscopies of which 242,756 were screening colonoscopies. The rate of overuse ranged credibly from 17 to 25.7%.Discussion: This study demonstrates that screening colonoscopy is regularly performed in the USA more often, and in populations older or younger, than recommended by national guidelines. Such overuse wastes resources and places patients at unnecessary risk of harm. Efforts to reduce non-indicated screening colonoscopy are needed. [ABSTRACT FROM AUTHOR]

Purpose: The prevalence of hyperdynamic left ventricular (LV) systolic function in septic patients and its impact on mortality remain controversial. In this systematic review and meta-analysis, we investigated the prevalence and association of hyperdynamic LV systolic function with mortality in patients with sepsis. Methods: We searched MEDLINE, Cochrane Central Register of Controlled Trials, and Embase. Primary outcomes were the prevalence of hyperdynamic LV systolic function in adult septic patients and the associated short-term mortality as compared to normal LV systolic function. Hyperdynamic LV systolic function was defined using LV ejection fraction (LVEF) of 70% as cutoff. Secondary outcomes were heart rate, LV end-diastolic diameter (LVEDD), and E/e' ratio. Results: Four studies were included, and the pooled prevalence of hyperdynamic LV systolic function was 18.2% ([95% confidence interval (CI) 12.5, 25.8]; I2 = 7.0%, P < 0.0001). Hyperdynamic LV systolic function was associated with higher mortality: odds ratio of 2.37 [95%CI 1.47, 3.80]; I2 = 79%, P < 0.01. No difference was found in E/e' (P = 0.43) between normal and hyperdynamic LV systolic function, while higher values of heart rate (mean difference: 6.14 beats/min [95%CI 3.59, 8.69]; I2 = 51%, P < 0.0001) and LVEDD (mean difference: − 0.21 cm [95%CI − 0.33, − 0.09]; I2 = 73%, P < 0.001) were detected in patients with hyperdynamic LV systolic function. Conclusion: The prevalence of hyperdynamic LV systolic function is not negligible in septic patients. Such a finding is associated with significantly higher short-term mortality as compared to normal LV systolic function. [ABSTRACT FROM AUTHOR]

Background: The surgical management of multinodular goiter is the treatment of choice for the majority of cases. There is controversy between radical resection with the lifelong thyroxine substitution and function-preserving resection with the risk for recurrence, and the complications associated with total thyroidectomy. Objective: The aim of the present study was to compare the outcome of total thyroidectomy (TT) in comparison with subtotal thyroidectomy (ST) as regards hypocalcemia, transient nerve injury, and recurrence rate. Patients and methods: This study included published English medical articles in the last 20 years, concerning the treatment of multinodular goiter. Results: Meta-analysis was for the evaluation of surgical outcomes after surgical management of multinodular goiter including total thyroidectomy versus subtotal thyroidectomy by comparing the TT versus ST in our study including 23 studies included of the total number of patients (4485) who underwent subtotal thyroidectomy versus the total number of patients (7116) who underwent total thyroidectomy; a comparison was done as regards postoperative complications including RLN injury (transient or permanent), rate of recurrence, need for reoperation, and incidence of postoperative hypocalcemia. The incidence of RLN injury is lower in ST compared to TT, and its recurrence is much lower in TT than in ST. Conclusion: This meta-analysis showed that the advantages of total thyroidectomy include adequate eradication of the disease, prevention of recurrent goiter, and avoidance of the need for completion surgery in case of occult malignancy, but it is associated with higher morbidity (postoperative thyroidectomy complications: RLN palsy and hypoparathyroidism) and the need for lifelong replacement therapy (L-thyroxin supplementation). [ABSTRACT FROM AUTHOR]

Lung cancer is the most prevalent cancer in the world, and the main treatment for advanced non-small cell lung cancer is immunotherapy combined with chemotherapy. In recent years, bTMB has received increasing attention as an emerging metric for monitoring the efficacy of tumour immunotherapy in terms of its operability, accessibility and real-time nature. We envisaged whether immunotherapy alone could be used to reduce the side effects of chemotherapy in patients with high bTMB lung cancer. We thus did a meta-analysis in order to show that immunotherapy alone is feasible in patients with high bTMB NSCLC. Methods This study aims to compare the efficacy of PD- 1/PD-L1 inhibitors (namely, atezolizumab, pembrolizumab, nivolumab, or tislelizumab) versus chemotherapy in NSCLC patients. The search for relevant studies was conducted in three major databases (i.e., PubMed, Embase, and Medline) up until January 2023. Specifically, we identified studies that reported risk ratios (HRs) for reporting progression-free survival (PFS) or overall survival (OS), or objective remission rates (ORs) for immunotherapy alone versus chemotherapy in high bTMB and low bTMB patient groups. Given that NSCLC represents the predominant type of lung cancer, we exclusively focused on this subtype. Our analysis encompassed a meta-analysis of the identified literature, incorporating heterogeneity analysis and sensitivity analysis. The quality of the evidence is evaluated using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach to ascertain the reliability and robustness of the findings. Result-We conducted a meta-analysis of seven randomised controlled trials including 4,755 patients with advanced non-small cell lung cancer (NSCLC) evaluated the efficacy of PD- 1 or PD-L1 monotherapy compared to chemotherapy alone. All patients were randomized to receive either PD- 1/PD-L1 treatment alone or chemotherapy alone as a control. In the high bTMB patient group, PD- 1/PD-L1 monotherapy resulted in significant improvements in overall survival (HR = 0.55, 95% CI 0.49–0.61, p = 0.77) and progression-free survival (HR = 0.74, 95% CI 0.68–0.81, p = 0.78) compared to chemotherapy alone. Conversely, in the low bTMB patient group, PD- 1 monotherapy or PD-L1 monotherapy failed to demonstrate significant improvements in overall survival (HR = 0.82, 95% CI 0.73–0.92, p = 0. 13) and progression-free survival (HR = 1.22, 95% CI 1.22- 1.45, p = 0.003) in advanced NSCLC. Conclusion Our analysis suggests that monotherapy with immunotherapy is a feasible option for patients with advanced NSCLC and high bTMB. However, the results have to be construed with caution because of the small sample size and the potential bias in the studies included. Therefore, further research with larger sample sizes and rigorous study designs is necessary to confirm the observed benefits of immunotherapy in this patient population. [ABSTRACT FROM AUTHOR]

Objective: To determine the overall surgical outcomes of infranotch T4b oral cancers and compare them with T4a oral cancers. Methods: PubMed, EMBASE and Cochrane databases from 2000 to 2022 were systematically searched. Clinical studies reporting at least one outcome following curative surgery and adjuvant therapy for comparison of patients with either infranotch T4b (IN–T4b) or T4a tumour. The heterogeneity of the included studies was determined using Tau-squared, Chi-squared, and the Higgins I2 test. The random effects model was used to determine the log odds ratio (logOR). Results: The systematic review comprised 11,790 patients from 16 included studies. Seven studies were included in the meta-analysis (n = 11,381). For IN–T4b patients, the pooled 2 and 5 year overall survival (OS) were 59.3% and 53.2%, 2 and 5 year disease-free survival (DFS) 57.9% and 48.4%, 2 and 5 year disease-specific survival (DSS) 72% and 68%, and 2 and 5 year local control (LC), 47% and 56%, respectively. There was no statistically significant difference in 2 year OS [logOR = 0.28 (−0.47, 1.03), p = 0.46, confidence interval (CI) = 95%], 5 year OS [logOR = 0.7 (−0.4, 1.8), p = 0.54, CI = 95%], 2 year DFS [logOR = 0.22 (−0.35, 0.79), p = 0.45, CI = 95%], 5 year DFS [logOR = 0.17 (−0.42, 0.77), p = 0.57, CI = 95%], 2 year LC [logOR = 0.47 (−0.33, 1.26), p = 0.25, CI = 95%] and 5 year LC [logOR = 0.34 (−0.31, 0.99), p = 0.31, CI = 95%] between IN–T4b and T4a oral cancers. Conclusion: Results of this meta-analysis suggest that IN–T4b oral cancers have similar outcomes to T4a oral cancers, which supports down-staging IN–T4b cancers to T4a cancers. [ABSTRACT FROM AUTHOR]

Background: Menstrual migraine is a subtype of migraine disease that is typically more disabling, longer-lasting, and more challenging to treat. The purpose of this network meta-analysis (NMA) is to compare the relative efficacy of treatments for menstrual migraine. Methods: We systematically searched databases, including PubMed, EMBASE, and Cochrane, and included all eligible randomized controlled trials in the study. We conducted the statistical analysis using Stata version 14.0, based on the frequentist framework. We used the Cochrane Risk of Bias tool for randomized trials version 2 (RoB2) to assess the risk of bias of the included studies. Results: This network meta-analysis included 14 randomized controlled trials with 4601 patients. For short-term prophylaxis, frovatriptan 2.5 mg twice daily had the highest probability of effectiveness [OR = 1.87 (95% CI: 1.48 to 2.38)] compared to placebo. For acute treatment, the results showed that sumatriptan 100 mg [OR = 4.32 (95% CI: 2.95 to 6.34)] was the most effective treatment compared to placebo. Conclusions: These findings suggest that frovatriptan 2.5 mg twice daily was best for short-term prevention, sumatriptan 100 mg were best for acute treatment. More high-quality randomized trials are required to determine the most effective treatment. [ABSTRACT FROM AUTHOR]

Background: While chronic exercise training has been demonstrated to be an effective non-pharmacological treatment for chronic low back pain (CLBP), there has been a relative lack of evidence or clinical guidelines for whether a posterior chain resistance training programme provides any benefits over general exercise (GE). Objectives: To determine if chronic posterior chain resistance training (PCRT), defined as exercise programmes of ≥6 weeks duration focused on the thoracic, lumbar and hip extensor musculature, is more effective than GE in improving pain, level of disability, muscular strength and the number of adverse events in recreationally active and sedentary individuals with CLBP. Methods: Four electronic databases were systematically searched from 25 September 2019 until 30 August 2020. Using the Joanna Briggs Institute (JBI) Critical Appraisal Tools checklist for randomized controlled trials (RCTs), articles were critically appraised and compared against the inclusion/exclusion criteria. Standardized mean difference (SMD), risk difference (RD) and confidence interval (CI) were calculated using Review Manager 5.3. Results: Eight articles were included, with a total of 408 participants (203 PCRT, 205 GE). Both PCRT and GE were effective in improving a number of CLBP-related outcomes, but these effects were often significantly greater in PCRT than GE, especially with greater training durations (i.e. 12–16 weeks compared to 6–8 weeks). Specifically, when compared to GE, PCRT demonstrated a greater reduction in pain (SMD = − 0.61 (95% CI − 1.21 to 0.00), p = 0.05; I2 = 74%) and level of disability (SMD = − 0.53 (95% CI − 0.97 to − 0.09), p = 0.02; I2 = 52%), as well as a greater increase in muscle strength (SMD = 0.67 (95% CI 0.21 to 1.13), p = 0.004; I2 = 0%). No differences in the number of adverse events were reported between PCRT and GE (RD = − 0.02 (95% CI − 0.10 to 0.05), p = 0.57; I2 = 72%). Conclusion: Results of the meta-analysis indicated that 12–16 weeks of PCRT had a statistically significantly greater effect than GE on pain, level of disability and muscular strength, with no significant difference in the number of adverse events for recreationally active and sedentary patients with CLBP. Clinicians should strongly consider utilizing PCRT interventions for 12–16 weeks with patients with CLBP to maximize their improvements in pain, disability and muscle strength. Future research should focus on comparing the efficacy and adverse events associated with specific PCRT exercise training and movement patterns (i.e. deadlift, hip lift) in treating this population. Trial registration: PROSPERO CRD42020155700. [ABSTRACT FROM AUTHOR]

Background: Over the past decade, nearly half of internal medicine residencies have implemented block clinic scheduling; however, the effects on residency-related outcomes are unknown. The authors systematically reviewed the impact of block versus traditional ambulatory scheduling on residency-related outcomes, including (1) resident satisfaction, (2) resident-perceived conflict between inpatient and outpatient responsibilities, (3) ambulatory training time, (4) continuity of care, (5) patient satisfaction, and (6) patient health outcomes.Method: The authors reviewed the following databases: Ovid MEDLINE, Ovid MEDLINE InProcess, EBSCO CINAHL, EBSCO ERIC, and the Cochrane Library from inception through March 2017 and included studies of residency programs comparing block to traditional scheduling with at least one outcome of interest. Two authors independently extracted data on setting, participants, schedule design, and the outcomes of interest.Results: Of 8139 studies, 11 studies of fair to moderate methodologic quality were included in the final analysis. Overall, block scheduling was associated with marked improvements in resident satisfaction (n = 7 studies, effect size range - 0.3 to + 0.9), resident-perceived conflict between inpatient and outpatient responsibilities (n = 5, effect size range + 0.3 to + 2.6), and available ambulatory training time (n = 5). Larger improvements occurred in programs implementing short (1 week) ambulatory blocks. However, block scheduling may result in worse physician continuity (n = 4). Block scheduling had inconsistent effects on patient continuity (n = 4), satisfaction (n = 3), and health outcomes (n = 3).Discussion: Although block scheduling improves resident satisfaction, conflict between inpatient and outpatient responsibilities, and ambulatory training time, there may be important tradeoffs with worse care continuity. [ABSTRACT FROM AUTHOR]

Purpose: The purpose of the study is to explore testicular sperm cryopreservation in patients with nonobstructive azoospermia (NOA) whether affect the outcome of subsequent intracytoplasmic sperm injection (ICSI).Methods: A systematic review and meta-analysis was conducted by searching the MEDLINE and EMBASE databases for relevant published studies in English language (1997-2017). Studies were eligible if they included the comparison of using fresh and frozen-thawed testicular sperm followed by ICSI. Two reviewers independently performed data extraction, quality assessment and assessed the risk of bias. The overall summary risk estimated the number of events. A meta-analysis was conducted using a random effects or fixed effects model analysis according to the test of heterogeneity.Results: A total of 17 studies with 1,261 ICSI cycles were identified. Analysis of the present data showed no difference in the fertilization outcome when comparing fresh versus frozen-thawed spermatozoa (RR = 1.02, 95% CI 0.86-1.09). Similarly, no difference in CR (RR = 1.01, 95% CI 0.96-1.05), good embryo rate (RR = 1.01, 95% CI 0.95-1.09), and IR (RR = 0.93, 95% CI 0.66-1.30) was observed if the spermatozoa was fresh or frozen-thawed. Finally, no difference in CPR or LBR was noted when using fresh or frozen-thawed cycles were analyzed separately (RR = 1.03, 95% CI 0.86-1.24; RR 1.11, 95% CI 0.88-1.41, respectively).Conclusions: In men with NOA, the ICSI outcome is not affected by whether the retrieved testicular sperm is fresh or frozen. Sperm cryopreservation ought to be considered in every surgical sperm retrieval case, which remain feasible even in patients with few testicular sperm retrieved. [ABSTRACT FROM AUTHOR]

Background: Despite the increasing awareness and interests about the importance of crime concentration at places, scholars have not comprehensively synthesized the body of evidence related to this thesis. We conduct a systematic review and meta-analysis of the evidence that crime is concentrated among places. Methods: We identified 44 studies that empirically examined crime concentration at place and provided quantitative information sufficient for analysis. We organized data using visual binning and fitted logarithmic curves to the median values of the bins. We examine concentration in two conditions: when all places are studied (prevalence), and when only places with at least one crime are studied (frequency). Results: We find that crime is concentrated at a relatively few places in both conditions. We also compared concentration for calls for services to reported crime incidents. Calls for services appear more concentrated than crime at places. Because there are several ways place is defined, we compared different units of analysis. Crime is more concentrated at addresses than other units, including street segments. We compared crime concentration over time and found less concentration in 2000s compared to 1980s and 1990s. We also compared crime concentration between U.S. and non-U.S. countries and found more concentration in U.S. Finally, violent crime is more concentrated than property crime. Conclusions: Though we systematically reviewed a comprehensive list of studies, summarizing this literature is problematic. Not only should more systematic reviews be conducted as more research becomes available, but future inquiries should examine other ways of summarizing these studies that could challenge our findings. [ABSTRACT FROM AUTHOR]

Background: Laparoscopic gastrectomy (LG) has been used as an alternative to open gastrectomy (OG) to treat early gastric cancer. However, the use of LG for advanced gastric cancer (AGC) has been in debate. Methods: Literature retrieval was performed by searching PubMed, EMBASE, and the Cochrane library up to July 2014. Potential studies comparing the surgical effects between LG with OG were evaluated and data were extracted accordingly. Meta-analysis was carried out using RevMan. The pooled risk ratio and weighted mean difference (WMD) with 95 % confidence interval (95 % CI) were calculated. Results: Overall, 26 studies were included in this meta-analysis. LG had some advantages over OG, including shorter hospitalization (WMD, −3.63, 95 % CI, −4.66 to −2.60; P < 0.01), less blood loss (WMD, −161.37, 95 % CI, −192.55 to −130.18; P < 0.01), faster bowel recovery (WMD, −0.78, 95 % CI, −1.05 to −0.50; P < 0.01), and earlier ambulation (WMD, −0.95, 95 % CI, −1.47 to −0.44; P < 0.01). In terms of surgical and oncological safety, LG could achieve similar lymph nodes (WMD, −0.49, 95 % CI, −1.78 to 0.81; P = 0.46), a lower complication rate [odds ratio (OR), 0.71, 95 % CI, 0.59 to 0.87; P < 0.01], and overall survival (OS) and disease-free survival (DFS) comparable to OG. Conclusions: For AGCs, LG appeared comparable with OG in short- and long-term results. Although more time was needed to perform LG, it had some advantages over OG in achieving faster postoperative recovery. Ongoing trials and future studies could help to clarify this controversial issue. [ABSTRACT FROM AUTHOR]