Category: Statistics

BMJ Open. 2021 Nov 1;11(11):e054777. doi: 10.1136/bmjopen-2021-054777.

ABSTRACT

INTRODUCTION: Major depressive disorder (MDD or depression) is prevalent among adults aged 65 years and older. The effectiveness and safety of interventions used to treat depression is often assessed through randomised controlled trials (RCTs). However, heterogeneity in the selection, measurement and reporting of outcomes in RCTs renders comparisons between trial results, interpretability and generalisability of findings challenging. There is presently no core outcome set (COS) for use in RCTs that assess interventions for older adults with MDD. We will conduct a methodological review of the literature for outcomes reported in trials for adults 65 years and older with depression to assess the heterogeneity of outcome measures.

METHODS AND ANALYSIS: RCTs evaluating pharmacotherapy, psychotherapy, or any other treatment intervention for older adults with MDD published in the last 10 years will be located using electronic database searches (MEDLINE, Embase, PsycINFO and the Cochrane Central Register of Controlled Trials). Reviewers will conduct title and abstract screening, full-text screening and data extraction of trials eligible for inclusion independently and in duplicate. Outcomes will be synthesised and mapped to core outcome-domain frameworks. We will summarise characteristics associated with trials and outcomes.

ETHICS AND DISSEMINATION: We hope that findings from our methodological review will reduce variability in outcome selection, measurement and reporting and facilitate the development of a COS for older adults with MDD. Our review will also inform evidence synthesis efforts in identifying the best treatment practices for this clinical population. Ethics approval is not required, as this study is a literature review.

PROSPERO REGISTRATION NUMBER: CRD42021244753.

PMID:34725082 | DOI:10.1136/bmjopen-2021-054777

Proc Natl Acad Sci U S A. 2021 Nov 9;118(45):e2108551118. doi: 10.1073/pnas.2108551118.

ABSTRACT

Fluids in natural systems, like the cytoplasm of a cell, often contain thousands of molecular species that are organized into multiple coexisting phases that enable diverse and specific functions. How interactions between numerous molecular species encode for various emergent phases is not well understood. Here, we leverage approaches from random-matrix theory and statistical physics to describe the emergent phase behavior of fluid mixtures with many species whose interactions are drawn randomly from an underlying distribution. Through numerical simulation and stability analyses, we show that these mixtures exhibit staged phase-separation kinetics and are characterized by multiple coexisting phases at steady state with distinct compositions. Random-matrix theory predicts the number of coexisting phases, validated by simulations with diverse component numbers and interaction parameters. Surprisingly, this model predicts an upper bound on the number of phases, derived from dynamical considerations, that is much lower than the limit from the Gibbs phase rule, which is obtained from equilibrium thermodynamic constraints. We design ensembles that encode either linear or nonmonotonic scaling relationships between the number of components and coexisting phases, which we validate through simulation and theory. Finally, inspired by parallels in biological systems, we show that including nonequilibrium turnover of components through chemical reactions can tunably modulate the number of coexisting phases at steady state without changing overall fluid composition. Together, our study provides a model framework that describes the emergent dynamical and steady-state phase behavior of liquid-like mixtures with many interacting constituents.

PMID:34725154 | DOI:10.1073/pnas.2108551118

AJNR Am J Neuroradiol. 2021 Nov 1. doi: 10.3174/ajnr.A7324. Online ahead of print.

ABSTRACT

BACKGROUND AND PURPOSE: Compared with BRAF p. V600E wild-type pleomorphic xanthoastrocytoma, BRAF p. V600E-mutant pleomorphic xanthoastrocytoma showed a higher survival rate. In this study, we focused on finding preoperative MR imaging differences between BRAF p. V600E mutant and wild-type in pleomorphic xanthoastrocytoma and anaplastic pleomorphic xanthoastrocytoma.

MATERIALS AND METHODS: Twenty-three patients with pathologically confirmed pleomorphic xanthoastrocytoma or anaplastic pleomorphic xanthoastrocytoma in our hospital were retrospectively analyzed from January 2015 to December 2020. They were divided into a BRAF p. V600E-mutant group (including 6 pleomorphic xanthoastrocytomas and 5 anaplastic pleomorphic xanthoastrocytomas) and a wild-type group (including 8 pleomorphic xanthoastrocytomas and 4 anaplastic pleomorphic xanthoastrocytomas). The preoperative MR imaging characteristics of these groups were statistically compared.

RESULTS: The wild-type pleomorphic xanthoastrocytoma group presented with more aggressive conventional and advanced MR imaging features than the mutant pleomorphic xanthoastrocytoma group, including greater mean maximum tumor diameter (3.1 [SD, 0.9] cm versus 1.7 [SD, 0.4 ] cm, P < .05), more frequent heterogeneous contrast enhancement of solid portions (100% versus 0%, P < .001), more obvious peritumoral edema (mean, [2.1 SD, 0.7] cm versus 0.6 [SD, 0.2] cm, P < .01), and lower mean minimum relative ADC (896 [SD, 86] versus 988 [SD, 73], P < .05) and mean relative ADC (1060 [SD, 159] versus 1248 [SD, 116], P < .05) on DWI. However, there was no significant difference in either conventional or advanced MR imaging features between the wild-type anaplastic pleomorphic xanthoastrocytoma group and the mutant anaplastic pleomorphic xanthoastrocytoma group.

CONCLUSIONS: Neurosurgeons should carefully interpret MR images before an operation and select appropriate surgical strategies according to genotype prediction.

PMID:34725042 | DOI:10.3174/ajnr.A7324

BMJ Open. 2021 Nov 1;11(11):e049884. doi: 10.1136/bmjopen-2021-049884.

ABSTRACT

INTRODUCTION: Activity-based therapy (ABT) is an important aspect of rehabilitation following traumatic spinal cord injury (SCI). Unfortunately, it has never been adapted to acute care despite compelling preclinical evidence showing that it is safe and effective for promoting neurological recovery when started within days after SCI. This article provides the protocol for a study that will determine the feasibility and explore potential benefits of early ABT in the form of in-bed leg cycling initiated within 48 hours after the end of spinal surgery for SCI.

METHODS AND ANALYSIS: PROMPT-SCI (protocol for rapid onset of mobilisation in patients with traumatic SCI) is a single-site single-arm proof-of-concept trial. Forty-five patients aged 18 years or older with a severe traumatic SCI (American Spinal Injury Association Impairment Scale grade A, B or C) from C0 to L2 undergoing spinal surgery within 48 hours of the injury will be included. Participants will receive daily 30 min continuous sessions of in-bed leg cycling for 14 consecutive days, initiated within 48 hours of the end of spinal surgery. The feasibility outcomes are: (1) absence of serious adverse events associated with cycling, (2) completion of 1 full session within 48 hours of spinal surgery for 90% of participants and (3) completion of 11 sessions for 80% of participants. Patient outcomes 6 weeks and 6 months after the injury will be measured using neurofunctional assessments, quality of life questionnaires and inpatient length of stay. Feasibility and patient outcomes will be analysed with descriptive statistics. Patient outcomes will also be compared with a matched historical cohort that has not undergone in-bed cycling using McNemar and Student’s t-tests for binary and continuous outcomes, respectively.

ETHICS AND DISSEMINATION: PROMPT-SCI is approved by the Research Ethics Board of the CIUSSS NIM. Recruitment began in April 2021. Dissemination strategies include publications in scientific journals and presentations at conferences.

TRIAL REGISTRATION NUMBER: NCT04699474.

PMID:34725077 | DOI:10.1136/bmjopen-2021-049884

Rev Gastroenterol Peru. 2021 Apr-Jun;41(2):94-102.

ABSTRACT

INTRODUCTION: Bile duct stones constitutes 20% of symptomatic gallbladder disease and difficult stones are one third of this. Endoscopic papillary large balloon dilation (EPLBD) with or without prior endoscopic sphincterotomy (EST) produces excellent outcomes for the treatment of complex or difficult common bile duct (CBD) stones, alone or combined with previous therapeutic options as mechanical lithotripsy (ML) and temporary or definitive stenting.

OBJECTIVES: Show success rate, complications and adverse events. Show that higher success rates are obtained combining ERCP techniques with no increase in complications.

MATERIALS AND METHODS: We evaluated the safety and therapeutic outcomes of EPLBD with vs. without EST and other combinations for the removal of difficult bile duct stones. We described our procedures for a decade and compare them with the previous decade without balloon dilation. Of 865 patients and procedures, 223 (25.78%) had difficult stones. Treatments where EPLBD with EST (n=183), EPLBD alone group (n=40). Additional modalities where required in 15.25% (n=34). These two groups were compared with respect to overall procedure-related adverse events, overall stone removal success rate, number of sessions required for complete stone removal, need for mechanical lithotripsy, temporal or definite stenting and total procedure time. Results Safety removal of stones was achieved in one session on 84.75% of cases with EPLBD. The incidence of adverse events was not significantly different between the groups (EPLBD alone vs. EPLBD with EST: overall adverse events 12.5% vs. 10.38% (including pain); pancreatitis 2.7% vs. 2.5%, p=0.62). Overall success similar, initial success similar, and the need for additional techniques were also similar between groups. Median total procedure time tended to be greater in the EPLBD alone group (20.5 minutes) than in the EPLBD with EST group. Conclusion DPBGD in ERCP allows bile duct stone extraction rates close to 99.65% (90% in previous decade) according to other reports of literature. Adverse events of EPLBD alone or with EST are similar between them and with classic ERCP without statistical difference and similar to other world series.

PMID:34724690

Anesth Analg. 2021 Sep 13. doi: 10.1213/ANE.0000000000005745. Online ahead of print.

ABSTRACT

At the outbreak of World War II (WWII), anesthesiology was struggling to establish itself as a medical specialty. The battlefield abruptly exposed this young specialty to the formidable challenge of mass casualties, with an urgent need to provide proper fluid resuscitation, airway management, mechanical ventilation, and analgesia to thousands. But while Europe was suffering under the Nazi boot, anesthesia was preparing to rise to the challenge posed by the impending war. While war brings death and destruction, it also opens the way to medical advances. The aim of this study is to measure the evolution of anesthesia owing to WWII. We conducted a retrospective observational bibliometric study involving a quantitative and statistical analysis of publications. The following 7 journals were selected to cover European and North American anesthesia-related publications: Anesthesia & Analgesia, the British Journal of Anaesthesia, Anesthesiology, Schmerz-Narkose-Anaesthesie, Surgery, La Presse Médicale, and The Military Surgeon (later Military Medicine). Attention was focused on journal volumes published between 1920 and 1965. After reviewing the literature, we selected 12 keywords representing important advances in anesthesiology since 1920: “anesthesia,” “balanced anesthesia,” “barbiturates,” “d-tubocurarine,” “endotracheal intubation,” “ether,” “lidocaine,” “morphine,” “spinal anesthesia,” “thiopental,” “transfusion,” and “trichloroethylene.” Titles of original articles from all selected journals editions between 1920 and 1965 were screened for the occurrence of 1 of the 12 keywords. A total of 26,132 original article titles were screened for the occurrence of the keywords. A total of 1815 keywords were found. Whereas Anesthesia & Analgesia had the highest keyword occurrence (493 citations), Schmerz-Narkose-Anaesthesie had the lowest (38 citations). The number of publications of the 12 keywords was significantly higher in the postwar than in the prewar period (65% and 35%, respectively; P < .001). Not surprisingly, the anesthesiology journals have a higher occurrence of keywords than those journals covering other specialties. The overall occurrence of keywords also showed peaks during other major conflicts, namely the Spanish Civil War (1936-1939), the Korean War (1950-1953), and the Vietnam War (1955-1975). For the first time, this study demonstrates statistically the impact of WWII on the progress of anesthesiology. It also offers an objective record of the chronology of the major advances in anesthesiology before and after the conflict. While the war arguably helped to enhance anesthesiology as a specialty, in return anesthesiology helped to heal the wounds of war.

PMID:34724677 | DOI:10.1213/ANE.0000000000005745

Anesth Analg. 2021 Sep 13. doi: 10.1213/ANE.0000000000005753. Online ahead of print.

ABSTRACT

BACKGROUND: Utilization of extracorporeal membrane oxygenation (ECMO) for adult critically ill patients is increasing, but data in obstetric cohorts are scant. This study analyzed ECMO utilization and maternal outcomes in obstetric patients in the United States.

METHODS: Data were abstracted from the 1999-2014 National Inpatient Sample (NIS), a 20% US national representative sample. ECMO hospitalizations (International Classification of Diseases, Ninth Revision, Clinical Modification [ICD-9-CM] code 39.65) in patients ≥15 years of age were categorized into obstetric ECMO and nonobstetric ECMO. Obstetric patients included 4 categories: (1) loss or termination of pregnancy, (2) delivery (term or preterm), (3) postdelivery hospitalization, and (4) pregnancy without an obstetrical outcome. Possible underlying causes for obstetric ECMO were identified by analysis of ICD-9-CM codes in individual records. In-hospital death was abstracted from the NIS, and ECMO complications were identified using ICD-9-CM algorithms. Statistical significance in time-effect was assessed using weighted regression models.

RESULTS: During the 16-year study period, 20,454 adult ECMO cases were identified, of which 331 occurred in obstetric patients (1.6%; 95% confidence interval [CI], 1.4-1.8). Obstetric ECMO utilization rate was 4.7 per million obstetric discharges (95% CI, 4.2-5.2). The top 3 possible indications were sepsis (22.1%), cardiomyopathy (16.6%), and aspiration pneumonia (9.7%). Obstetric ECMO utilization rate increased significantly during the study period from 1.1 per million obstetric discharges in 1999-2002 (95% CI, 0.6-1.7) to 11.2 in 2011-2014 (95% CI, 9.6-12.9), corresponding to a 144.7% increase per 4-year period (95% CI, 115.3-178.1). Compared with nonobstetric ECMO, obstetric ECMO was associated with decreased in-hospital all-cause mortality (adjusted odds ratio [aOR] 0.78; 95% CI, 0.66-0.93). In-hospital all-cause mortality for obstetric ECMO decreased from 73.7% in 1999-2002 (95% CI, 48.8-90.8) to 31.9% in 2011-2014 (95% CI, 25.2-39.1), corresponding to a 26.1% decrease per 4-year period (95% CI, 10.1-39.3). Compared with nonobstetric ECMO, obstetric ECMO was associated with significantly increased risk of both venous thromboembolism without associated pulmonary embolism (aOR 1.83; 95% CI, 1.06-3.15) and of nontraumatic hemoperitoneum (aOR 4.32; 95% CI, 2.41-7.74).

CONCLUSIONS: During the study period, obstetric ECMO utilization has increased significantly and maternal prognosis improved.

PMID:34724684 | DOI:10.1213/ANE.0000000000005753

Obes Facts. 2021 Nov 1:1-8. doi: 10.1159/000519946. Online ahead of print.

ABSTRACT

INTRODUCTION: Lockdown due to the COVID-19 pandemic has caused gym closures and adjustments to ongoing weight loss programs were needed in order to keep the programs running. Little is known whether adjustments affected the success of weight reduction. Weight reduction of at least 5% is related to improved fertility and better pregnancy outcomes in obese women. This study compared success of the weight loss program in infertile polycystic ovary syndrome women with obesity who attended the program before and during lockdown due to COVID-19 pandemic. Furthermore, we checked whether there were any differences in spontaneous pregnancy rates between both groups at the end of the program.

METHODS: Altogether, 27 women were prospectively included to the weight loss program. Twelve women attended the 8 – week program before COVID-19 pandemic. Fifteen women began the program before the lockdown and ended it during lockdown. Due to lockdown, the program was prolonged for 4 weeks and taken online.

RESULTS: On average, prior to lockdown women achieved a BMI reduction of 6.8% whereas women that attended the program during the lockdown reduced their BMI for 3.7%. This difference was not statistically significant. No significant differences were seen in other measured anthropometric and endocrine parameters between both groups. Furthermore, there were no differences in spontaneous pregnancy rates between both groups. In women who reduced their BMI for 5% or more, spontaneous pregnancy rate was 29.4%.

DISCUSSION/CONCLUSIONS: Although statistical significance has not been reached in the present study, we have shown that lockdown due to COVID-19 pandemic has led to almost half lower BMI reduction despite adaptations and longer duration of the weight loss program. On average, BMI in the group of women that attended the program during lockdown was 3.7% lower after the end of the weight loss program. This means they did not reach the wanted 5% reduction which is known to improve fertility. We have also shown that weight reduction is the correct approach for treating infertile women with obesity, as almost 30% of those who reduced their body weight by 5% or more conceived spontaneously.

PMID:34724671 | DOI:10.1159/000519946

Eur Surg Res. 2021 Nov 1. doi: 10.1159/000520386. Online ahead of print.

ABSTRACT

OBJECTIVES: The disruption to surgical training and medical education caused by the global COVID-19 pandemic highlighted the need for realistic, reliable, and engaging educational opportunities available outside of the operating theatre and accessible for trainees of all levels. This paper presents the design and development of a virtual reality curriculum which simulates the surgical mentorship experience outside of the operating theatre, with a focus on surgical anatomy and surgical decision making.

METHOD: This was a multi-institutional study between London’s King’s College and Imperial College. The index procedure selected for the module was robotic radical prostatectomy. For each stage of the surgical procedure, subject-matter experts (N=3) at King’s College London, identified: (1) the critical surgical-decision making points, (2) critical anatomical landmarks and (3) tips and techniques for overcoming intraoperative challenges. Content validity was determined by an independent panel of subject-matter experts (N=8) at Imperial College, London using Fleiss’ Kappa statistic. The experts’ teaching points were combined with operative footage and illustrative animations and projected onto a virtual reality headset. The module was piloted to Surgical Science students (N=15). Quantitative analysis compared participants’ confidence regarding their anatomical knowledge before and after taking the module. Qualitative data was gathered from students regarding their views on using the virtual reality model.

RESULTS: Multi-rater agreement between experts was above the 70.0% threshold for all steps of the procedure. 73% of pilot study participants ‘agreed’ or ‘strongly agreed’ that they achieved a better understanding of surgical anatomy and the rationale behind each procedural step. This was reflected in an increase in the median knowledge score after trialing the curriculum (p<0.001). 100% of subject-matter experts and 93.3% of participants ‘agreed’ or ‘strongly agreed’ that virtual mentorship would be useful for future surgical training.

CONCLUSIONS: This study demonstrated that virtual surgical mentorship could be a feasible and cost-effective alternative to traditional training methods with the potential to improve technical skills, such as operative proficiency and non-technical skills such as decision-making and situational judgement. .

PMID:34724676 | DOI:10.1159/000520386

Neurosurg Focus. 2021 Nov;51(5):E10. doi: 10.3171/2021.8.FOCUS20892.

ABSTRACT

OBJECTIVE: Microsurgery plays an essential role in managing unruptured intracranial aneurysms (UIAs). The Clavien-Dindo classification is a therapy-oriented grading system that rates any deviation from the normal postoperative course in five grades. In this study, the authors aimed to test the applicability of the Clavien-Dindo grade (CDG) in patients who underwent microsurgical treatment of UIAs.

METHODS: The records of patients who underwent microsurgery for UIAs (January 2013-November 2018) were retrieved from a prospective database. Complications at discharge and at short-term follow-up (3 months) were rated according to the Clavien-Dindo system. Patient outcomes were graded using the modified Rankin Scale (mRS) and the National Institutes of Health Stroke Scale (NIHSS). A descriptive statistic was used for data analysis.

RESULTS: Overall, 156 patients underwent 157 surgeries for 201 UIAs (size range 4-42 mm). Thirty-nine patients (25%) had complex UIAs. An adverse event (CDG ≥ I) occurred in 21 patients (13.5%) by the time of discharge. Among these, 10 patients (6.4%) presented with a new neurological deficit. Significant correlations existed between a CDG ≥ I and an increase in mRS and NIHSS scores (p < 0.001). Patients treated for complex aneurysms had a significantly higher risk of developing new neurological deficits (20.5% vs 1.7%, p = 0.007). At the 3-month follow-up, a CDG ≥ I was registered in 16 patients (10.3%); none presented with a new neurological deficit. A CDG ≥ I was associated with a longer hospital length of stay (LOS) (no complication vs CDG ≥ I, 6.2 ± 3.5 days vs 9.3 ± 7.7 days, p = 0.02).

CONCLUSIONS: The CDG was applicable to patients who received microsurgery of UIAs. A significant correlation existed between CDG and outcome scales, as well as LOS. The aneurysm complexity was significantly associated with a higher risk for new neurological deficit.

PMID:34724644 | DOI:10.3171/2021.8.FOCUS20892