Terracotta: A tool for conducting experimental research on student learning.

For researchers seeking to improve education, a common goal is to identify teaching practices that have causal benefits in classroom settings. To test whether an instructional practice exerts a causal influence on an outcome measure, the most straightforward and compelling method is to conduct an experiment. While experimentation is common in laboratory studies of learning, experimentation is increasingly rare in classroom settings, and to date, researchers have argued it is prohibitively expensive and difficult to conduct experiments on education in situ. To address this challenge, we present Terracotta (Tool for Education Research with RAndomized COnTrolled TriAls), an open-source web application that integrates with a learning management system to provide a comprehensive experimental research platform within an online class site. Terracotta automates randomization, informed consent, experimental manipulation of different versions of learning activities, and export of de-identified research data. Here we describe these features, and the results of a live classroom demonstration study using Terracotta, a preregistered replication of McDaniel et al. (Journal of Applied Research in Memory and Cognition, 1(1), 18-26, 2012). Using Terracotta, we experimentally manipulated online review assignments so that consenting students alternated, on a weekly basis, between taking multiple-choice quizzes (retrieval practice) and reading answers to these quizzes (restudy). Students' performance on subsequent exams was significantly improved for items that had been in retrieval practice review assignments. This successful replication demonstrates that Terracotta can be used to experimentally manipulate consequential aspects of students' experiences in education settings.

External validation of the Japanese difficulty score for laparoscopic hepatectomy in patients undergoing robotic-assisted hepatectomy.

INTRODUCTION: The Japanese difficulty score (JDS) categorizes laparoscopic hepatectomy into low, intermediate, and high complexity procedures, and correlates with operative and postoperative outcomes. We sought to perform a validation study to determine if the JDS correlates with operative and postoperative indicators of surgical complexity for patients undergoing robotic-assisted hepatectomy. METHODS: Retrospective review of 657 minimally invasive hepatectomy procedures was performed between January 2008 through March 2019. Outcomes included operative time, estimated blood loss (EBL), blood transfusion, complications, post-hepatectomy liver failure (PHLF), length of stay, 30-day readmission, and 30-day and 90-day mortality. Patients were grouped based on JDS defined as: low (< 4), intermediate (4-6), and high (7 +) complexity procedures. Statistical comparisons were analyzed by ANOVA or χ2 test. RESULTS: 241 of 657 patients underwent robotic-assisted resection. Of these patients, 137 were included in the analysis based on JDS: 25 low, 58 intermediate, and 54 high. High JDS was associated with more major resections (≥ 4 contiguous segments) versus minor resections (median JDS 8 vs. 5, P < 0.0001). High JDS was associated with significantly longer operative times, higher EBL, and more blood transfusions. High JDS was associated with higher rates of PHLF at 16.7%, compared with 5.2% intermediate and 0.0% low, (P = 0.018). Complication rates, 30-day readmissions, and mortality rates were similar between groups. Median LOS was longer in patients with high JDS compared with intermediate and low (4 days vs. 3 days vs. 2 days; P = 0.0005). DISCUSSION: Higher JDS was associated with multiple indicators of operative complexity, including greater extent of resection, increased operative time, EBL, blood transfusion, PHLF, and LOS. This validation study supports the ability of the JDS to categorize patients undergoing robotic-assisted hepatectomy by complexity.

Major hepatectomy in elderly patients: possible benefit from robotic platform utilization.

INTRODUCTION: Robotic surgery has been increasingly utilized, yet its application for hepato-pancreato-biliary (HPB) procedures remains low due to technical complexity, perceived financial burden, and unproven clinical benefits. We hypothesized that the robotic approach would be associated with improved clinical outcomes following major hepatectomy compared with the laparoscopic approach among elderly patients who would benefit from the advantages of minimally invasive surgery. METHODS: A retrospective review of consecutive patients who underwent major hepatectomy between January 2010 and December 2021 at Carolinas Medical Center was performed. Inclusion criteria were age ≥ 65 years and major hepatectomy of three segments or more. Patients who underwent multiple liver resections, vascular/biliary reconstruction, or concomitant extrahepatic procedures (except cholecystectomy) were excluded. Categorical variables were compared using Chi-square or Fisher's exact test when more than 20% of cells had expected frequencies less than five, and Wilcoxon two-sample or Kruskal-Wallis tests were used for continuous or ordinal variables. Results are described as median and interquartile range (IQR). Multivariate analyses were used on postoperative admission days. RESULTS: There were 399 major hepatectomies performed during this time period, of which 125 met the criteria and were included. There were no differences in perioperative demographics among patients who underwent robotic hepatectomy (RH, n = 39) and laparoscopic hepatectomy (LH, n = 32). There was no difference in operative time, blood loss, or major complication rates. However, RH had lower rates of conversion to an open procedure (2.6% versus 31.3%, p = 0.002), shorter length of hospital stay [LOS, 4 (3-7) versus 6 (4-8.5) days, p ≤ 0.0001], cumulative LOS [4 (3-7) versus 6 (4.5-9) days, p ≤ 0.0001], and lower rates of intensive care unit (ICU) admission (7.7% versus 75%, p ≤ 0.001), with a trend toward fewer rehabilitation requirements. CONCLUSIONS: Robot major hepatectomy shows clinical advantages in elderly patients, including shorter hospital and ICU stays. These advantages, as well as reduced rehabilitation requirements associated with minimally invasive surgery, could overcome the current perceived financial disadvantages of robotic hepatectomy.

Irreversible Electroporation-Assisted Resection for Locally Advanced Pancreas Cancer.

BACKGROUND: A significant number of patients with advanced pancreatic cancer are unable to undergo resection due to vascular involvement. Irreversible electroporation (IRE) has shown promise in improving survival. This study sought to assess a novel IRE application whereby IRE was performed pre-resection to alter tissue plasticity and assist tumor removal from underlying vasculature when surgical excision was otherwise precluded. METHODS: After multidisciplinary evaluation appropriate patients were consented for IRE therapy. All IRE cases were tracked prospectively using an institutional review board-approved database that was retrospectively queried for patients undergoing IRE-assisted resection (IRE-AR) for pancreatic adenocarcinoma located in the head/uncinate process. Patients who underwent other IRE therapy or had disease location elsewhere were excluded. RESULTS: 5 patients met the study inclusion criteria with a mean tumor size of 3.2 cm (range 2.4-4.1 cm). Using IRE-AR median recurrence free survival was 10.6 months, with 21.6 month overall survival. The average comprehensive complication index score was 23.23. One patient had grade 3 [or higher] complications and there were no 90 day mortalities. DISCUSSION: Employing a high-starting voltage for ablation along resection margins allows for resection when margins are anticipated to be positive. Patients with locally advanced pancreatic adenocarcinoma who underwent IRE-AR had promising outcomes. CONCLUSION: This study reports IRE-AR as a novel approach for resecting locally advanced pancreatic adenocarcinoma. A prospective trial of IRE-AR for inoperable pancreatic adenocarcinoma will provide additional data for the long-term application of this approach.

Wild brooms and learning analytics.

In this commentary we present an analogy between Johann Wolfgang Von Goethe's classic poem, The Sorcerer's Apprentice, and institutional learning analytics. In doing so, we hope to provoke institutions with a simple heuristic when considering their learning analytics initiatives. They might ask themselves, "Are we behaving like the sorcerer's apprentice?" This would be characterized by initiatives lacking faculty involvement, and we argue that when initiatives fit this pattern, they also lack consideration of their potential hazards, and are likely to fail. We join others in advocating for institutions to, instead, create ecosystems that enable faculty leadership in institutional learning analytics efforts.

Robotic Resection of Gallbladder Cancer: A Single-Center Retrospective Comparative Study to Open Resection.

BACKGROUND: Minimally invasive surgery is gaining support for resection of gallbladder cancer (GBC). This study aims to compare operative and early outcomes of robotic resection (RR) to open resection (OR) from a single institution performing a high volume of robotic HPB surgery. METHODS: Twenty patients with GBC underwent RR from January 2013 to August 2019. Outcomes were compared to a historical control of 23 patients with OR. Radical cholecystectomy for suspected GBC and completion operations for incidental GBC after routine cholecystectomy were both included. RESULTS: Robotic resection had lower blood loss compared to OR (150 vs 350 mL, P = .002) and shorter postoperative length of stay (2.5 vs 6 days, P < .001), while median operative time was similar (193 vs 208 min, P = .604). There were no statistical differences in 30-day major complications or readmissions. No 30-day mortalities occurred. There was no statistical difference in survival trend (P = .438) or median lymph node harvest (5 vs 3, P = .189) for RR compared to OR. CONCLUSION: Robotic resection of GBC is safe and efficient, with lower length of hospital stay and blood loss compared to OR. Technical benefits of robotic-assisted surgery may prove advantageous though larger studies are still needed.

Hepatolithiasis caused by right hepatic artery branches forming an arterial ring compressing the common hepatic duct.

Anatomic variations of the hepatic artery do not usually cause biliary obstruction. We present a 51-year-old male who developed biliary obstruction and hepatolithiasis due to extrinsic compression of the common hepatic duct (CHD) by an arterial ring formed by the anterior and posterior branches of the right hepatic artery. We performed a surgical bile duct exploration and used intraoperative direct cholangioscopy to guide clearance of hepatolithiasis. Herein, we review the existing literature on CHD compression caused by topographical variants of the hepatic artery and discuss diagnostic and treatment strategies.

Generalizability, transferability, and the practice-to-practice gap.

Emphasizing the predictive success and practical utility of psychological science is an admirable goal but it will require a substantive shift in how we design research. Applied research often assumes that findings are transferable to all practices, insensitive to variation between implementations. We describe efforts to quantify and close this practice-to-practice gap in education research.

Long-Term Clinical Outcomes of an Antibiotic-Coated Non-Cross-linked Porcine Acellular Dermal Graft for Abdominal Wall Reconstruction for High-Risk and Contaminated Wounds.

BACKGROUND: Abdominal wall reconstruction in high-risk and contaminated cases remains a challenging surgical dilemma. We report long-term clinical outcomes for a rifampin-/minocycline-coated acellular dermal graft (XenMatrix™ AB) in complex abdominal wall reconstruction for patients with a prior open abdomen or contaminated wounds. METHODS: Patients undergoing abdominal wall reconstruction at our institution at high risk for surgical site occurrence and reconstructed with XenMatrix™ AB with intent-to-treat between 2014 and 2017 were included. Demographics, operative characteristics, and outcomes were collected. The primary outcome was hernia recurrence. The secondary outcomes included length of stay, surgical site occurrence, readmission, morbidity, and mortality. RESULTS: Twenty-two patients underwent abdominal wall reconstruction using XenMatrix™ AB during the study period. Two patients died while inpatient from progression of their comorbid diseases and were excluded. Sixty percent of patients had an open abdomen at the time of repair. All patients were from modified Ventral Hernia Working Group class 2 or 3. There were a total of four 30-day infectious complications including superficial cellulitis/fat necrosis (15%) and one intraperitoneal abscess (5%). No patients required reoperation or graft excision. Median clinical follow-up was 38.2 months with a mean of 35.2 +/- 18.5 months. Two asymptomatic recurrences and one symptomatic recurrence were noted during this period with one planning for elective repair of an eventration. Follow-up was extended by phone interview which identified no additional recurrences at a median of 45.5 and mean of 50.5 +/-12.7 months. CONCLUSION: We present long-term outcomes for patients with high-risk and contaminated wounds who underwent abdominal wall reconstruction reinforced with XenMatrix™ AB to achieve early, permanent abdominal closure. Acceptable outcomes were noted.

Visual Search Asymmetry Due to the Relative Magnitude Represented by Number Symbols.

In visual search tasks, physically large target stimuli are more easily identified among small distractors than are small targets among large distractors. The present study extends this finding by presenting preliminary evidence of a new search asymmetry: stimuli that symbolically represent larger magnitude are identified more easily among featurally equivalent distractors that represent smaller magnitude. Participants performed a visual search task using line-segment digits representing the numbers 2 and 5, and the numbers 6 and 9, as well as comparable non-numeric control stimuli. In three experiments, we found that search times are faster when the target is a digit that represents a larger magnitude than the distractor, although this pattern was not evident in one additional experiment. The results provide suggestive evidence that the magnitude of a number symbol can affect perceptual comparisons between number symbols, and that the semantic meaning of a target stimulus can systematically affect visual search.

Mitigating clinical waste in the trauma intensive care unit: Limited clinical utility of cardiac troponin testing for trauma patients with atrial fibrillation.

BACKGROUND: The clinical significance of obtaining cardiac troponin (cTn) levels among trauma patients with new onset arrhythmias is unknown. We aimed to assess whether cTn levels actually influence clinical decision making or represent an inappropriate use of resources. METHODS: Trauma patients admitted from 2013 to 2014 diagnosed with atrial fibrillation (AF) were retrospectively reviewed using the institutional trauma database. Demographics, cTn levels, and myocardial infarction (MI) diagnosis data were recorded. Standard univariate tests were used to compare data between patients with and without cTn. RESULTS: There were 258 patients included of which 126 patients had cTn levels obtained (48.8%, TEST group). The remaining 132 patients (51.2%) were untested (noTEST group). Among TEST patients, use of echocardiography nearly doubled and cardiology consultations increased (all p < 0.05). No TEST patients suffered MI or PE. CONCLUSIONS: Obtaining cTn values in trauma patients with new-onset AF resulted in increased resource utilization without clinical utility.

Frequency of unplanned surgery in patients with stage IV colorectal cancer receiving palliative chemotherapy with an intact primary: An analysis of SEER-Medicare.

BACKGROUND AND OBJECTIVES: Stage IV colorectal cancer is often treated with palliative chemotherapy with the primary tumor in place. Low rates of unplanned surgical intervention (due to obstruction or perforation) have been reported. We examined a large national dataset to determine the rate of unplanned surgical intervention in these patients. METHODS: Surveillance Epidemiology and End Results-Medicare were queried for patients with metastatic colorectal cancer receiving chemotherapy (1998-2013). Patient who underwent planned surgery to the primary or metastasectomy were excluded. The primary outcome was the need for nonelective surgery. Time to surgery or death was measured. Conditional analyses were performed to determine the risk of surgical intervention at 6-month, 1-, and 2-year after diagnosis. RESULTS: The analytic cohort consisted of 4692 patients (median age = 75). At 24 months, 80% of the patients had died. The overall unplanned intervention rate was 12%. The probability of requiring unplanned surgery between 6 and 12 months was 8.1%; 12 and 24 months = 6.7%, and >24 months = 5.3%. Males, those with right-sided tumors, and older patients were less likely to require surgery. CONCLUSIONS: Patients treated with palliative chemotherapy who are not resected upfront are unlikely to require unplanned surgery. Prophylactic surgery to reduce the risk of perforation or obstruction may not be necessary.

Enteral Feeding Access Has an Impact on Outcomes for Patients with Esophageal Cancer Undergoing Esophagectomy: An Analysis of SEER-Medicare.

BACKGROUND: Optimal nutrition after esophagectomy is challenging due to alterations in eating, both from the tumor and during surgical recovery. Enteral nutrition via feeding tube is commonly used. The impact of feeding tubes on post-esophagectomy outcomes was examined in a large national data set. METHODS: Patients with esophageal cancer (1998-2013) undergoing esophagectomy were extracted from the Surveillance Epidemiology and End Results-Medicare database. Chi-square and t tests were used to compare categorical and continuous variables. Time trend analyses were performed with Cochran-Armitage survival using log-rank and multivariable analysis with generalized linear modeling. RESULTS: The study examined 2495 patients. The majority had enteral feeding access (71%, n = 1794) during the perioperative period. Mortality among the patients with feeding tubes was lower at 30 days (5.4% vs 8.4%), 60 days (9.0% vs 13.0%), and 90 days (12.2% vs 15.8%). In the multivariable analysis, the patients with feeding tubes had improved short-term survival at 30 days (odds ratio [OR], 0.65, 95% confidence interval [CI], 0.46-0.93), 60 days (OR, 0.64; 95% CI, 0.49-0.85), and 90 days (OR, 0.70; 95% CI, 0.54-0.90). The hospital stay was shorter for the patients undergoing enteral feeding tube placement (17.9 vs 19.5 days; p = 0.04). Discharge destination (home vs health care facility) showed no difference. CONCLUSIONS: Feeding tubes in patients undergoing esophagectomy were associated with an increase in short-term survival up to 90 days after surgery. Feeding tube placement was not associated with higher rates of non-home discharges and did not prolong the hospital stay.

Minimally Invasive Ivor Lewis Esophagectomy Without Patient Repositioning.

INTRODUCTION: The standard technique for Ivor Lewis minimally invasive esophagectomy involves a two-stage approach necessitating repositioning mid-procedure. TECHNIQUE: We describe our technique for a one-stage hand-assisted minimally invasive esophagectomy that allows sequential access to the chest and abdomen within the same surgical field, eliminating the need for repositioning. The patient is positioned in a "corkscrew" configuration with the abdomen supine and the chest rotated to the left to allow access to the right chest. The abdomen and chest are prepped into a single operative field. This technique allows sequential access to the abdomen for gastric mobilization, chest for division of the esophagus, abdomen for construction of the gastric conduit, and chest for intrathoracic anastomosis. CONCLUSION: This approach enables extracorporeal construction of the conduit, which helps ensure a clear distal margin on the specimen and facilitates conduit length by placing the stomach on stretch during stapling.

Quality Improvement in Minimally Invasive Esophagectomy: Outcome Improvement Through Data Review.

BACKGROUND: Esophagectomy is a complex operation in which outcomes are profoundly influenced by operative experience and volume. We report the effects of experience and innovation on outcomes in minimally invasive esophagectomy. METHODS: Esophageal resections for cancer from 2007 to 2016 at Levine Cancer Institute at Carolinas Medical Center (Charlotte, NC) were reviewed. During this time, three changes in technique were made to improve outcomes: vascular evaluation of the gastric conduit to improve anastomotic healing (beginning at case #63), one-stage approach to permit access to abdomen and chest through one draped surgical field (case #82), and adoption of a lung-protective anesthetic protocol (case #101). Mortality, operative time, complications, and length of stay were analyzed relative to these interventions using GLM regression. RESULTS: 200 patients underwent minimally invasive esophagectomy. There were no mortalities at 30 days, and no change in mortality rate at 60 and 90 days. Anastomotic leak decreased significantly after the introduction of intraoperative vascular evaluation of the gastric conduit (3.6 vs 19.4%). Operative time decreased with adoption of a one-stage approach (416 vs 536 min). Pulmonary complications decreased coincident with a change in anesthetic technique (pneumonia 6 vs 28%). Lymph node harvest increased over time. Length of stay was driven primarily by complications and decreased with operative experience. CONCLUSIONS: Postoperative complications, operative time, and length of stay decreased with case experience and alterations in surgical and anesthetic technique. We believe that adoption of the techniques and technology described herein can reduce complications, reduce hospital stay, and improve patient outcomes.

Chemical Components Separation: Concepts, Evidence, and Outcomes.

Ventral hernias with loss of domain pose a significant challenge to the hernia surgeon. Techniques such as advancement flaps, component separation, progressive pneumoperitoneum, and preoperative injection of botulinum toxin A (BTA) aim to alter the abdominal wall length or form to achieve tension-free primary fascial repair in abdominal wall reconstruction (AWR). Here, we review the current literature on BTA injection as an adjunct to AWR. A literature review identified 22 articles discussing the use of BTA associated with ventral hernia repair. Six primary studies reported preoperative use of BTA. Treatment regimens are not standardized, varying from 300 to 500 u injection on 3-5 sites per laterality, from 4 weeks before the day of surgery. After injection, computed tomography scans demonstrate elongated and thinned abdominal wall muscles with decreased mean defect size and hernia size. Primary fascial closure is usually achieved. Postoperative pain control may be improved with perioperative administration of BTA, and no adverse events associated with BTA injection were reported. Preoperative BTA injection is a promising adjunct to AWR, creating abdominal wall laxity and enabling primary fascial repair. Further investigation will be needed to determine the ideal dosage, timing, and patient population.

Optimal Lymphadenectomy in Small Bowel Neuroendocrine Tumors: Analysis of the NCDB.

BACKGROUND: Current National Comprehensive Cancer Network guidelines for resectable small bowel neuroendocrine tumors (NETs) recommend regional lymphadenectomy. However, no consensus exists on the optimal nodal harvest. METHODS: The National Cancer Database was queried for patients with resectable small bowel NETs (1998-2013). Patients with metastatic disease and missing lymph node harvest data were excluded. We performed logistic regression of factors determining nodal positivity and multivariable survival analyses. RESULTS: Of 11,852 patients, 81.8% underwent lymphadenectomy. 79.3% were node positive (N+) and 46.9% of patients had tumors < 1 cm. Independent predictors of N+ were large tumor size, ileal location, and neuroendocrine carcinoma histology. Logistic regression found no difference between observed and expected proportions of N+ patients with lymphadenectomy greater than or equal to eight nodes. Lower metastatic node ratio predicted improved survival on multivariable analysis and is associated with high-volume institutions. CONCLUSION: Small bowel NETs have high rates of nodal metastasis, even in patients with small tumors, and many patients do not undergo lymphadenectomy despite the clear benefit. Lymphadenectomy of eight nodes is optimal to identify N+ patients. Additionally, minimizing metastatic node ratio with complete regional lymphadenectomy is associated with improved survival in these patients.

A dissociation between engagement and learning: Enthusiastic instructions fail to reliably improve performance on a memory task.

Despite widespread assertions that enthusiasm is an important quality of effective teaching, empirical research on the effect of enthusiasm on learning and memory is mixed and largely inconclusive. To help resolve these inconsistencies, we conducted a carefully-controlled laboratory experiment, investigating whether enthusiastic instructions for a memory task would improve recall accuracy. Scripted videos, either enthusiastic or neutral, were used to manipulate the delivery of task instructions. We also manipulated the sequence of learning items, replicating the spacing effect, a known cognitive technique for memory improvement. Although spaced study reliably improved test performance, we found no reliable effect of enthusiasm on memory performance across two experiments. We did, however, find that enthusiastic instructions caused participants to respond to more item prompts, leaving fewer test questions blank, an outcome typically associated with increased task motivation. We find no support for the popular claim that enthusiastic instruction will improve learning, although it may still improve engagement. This dissociation between motivation and learning is discussed, as well as its implications for education and future research on student learning.

Pathologic Complete Response Rates After Neoadjuvant Treatment in Rectal Cancer: An Analysis of the National Cancer Database.

BACKGROUND: Pathologic complete response (pCR) of rectal cancer following neoadjuvant therapy is associated with decreased local recurrence and increased overall survival. This study utilizes a national dataset to identify predictors of pCR in patients with rectal cancer. METHODS: The National Cancer Database was queried for patients with nonmetastatic rectal cancer (2004-2014) who underwent neoadjuvant therapy and surgical resection. Unadjusted associations were assessed using rank-sum tests and χ 2 tests where appropriate. Backward elimination and forward selection multivariable logistic regression models were created to determine the relationship of annual surgical volume with pCR rate, adjusting for preoperative characteristics and radiation-surgery interval. Statistical tests were two-sided, with a significance level of p ≤ 0.05. Analyses were performed using SAS version 9.4. RESULTS: A total of 27,532 patients from 1179 participating hospitals met the inclusion criteria. Generalized linear mixed models demonstrated that the odds of achieving pCR was independently associated with more recent diagnosis, female sex, private insurance, lower grade, lower clinical T classification, lower clinical N classification, increasing interval between the end of radiation and surgery, and treatment at higher-volume institutions. CONCLUSIONS: pCR was associated with favorable tumor factors, insurance status, time between radiation and surgery, and institutional volume. It is not clear what is driving the higher rates of pCR at high-volume institutions. Research targeted at understanding processes that are associated with pCR in high-volume institutions is needed so that similar results can be achieved across the spectrum of facilities caring for patients in this population.

An In Vivo Study of Self-Regulated Study Sequencing in Introductory Psychology Courses.

Study sequence can have a profound influence on learning. In this study we investigated how students decide to sequence their study in a naturalistic context and whether their choices result in improved learning. In the study reported here, 2061 undergraduate students enrolled in an Introductory Psychology course completed an online homework tutorial on measures of central tendency, a topic relevant to an exam that counted towards their grades. One group of students was enabled to choose their own study sequence during the tutorial (Self-Regulated group), while the other group of students studied the same materials in sequences chosen by other students (Yoked group). Students who chose their sequence of study showed a clear tendency to block their study by concept, and this tendency was positively associated with subsequent exam performance. In the Yoked group, study sequence had no effect on exam performance. These results suggest that despite findings that blocked study is maladaptive when assigned by an experimenter, it may actually be adaptive when chosen by the learner in a naturalistic context.