Self-stigma, religiosity, and perceived social support in people with recent-onset psychosis in the Islamic Republic of Iran: Associations with symptom severity and psychosocial functioning.

AIMS: Most evidence on psychosocial factors in recent-onset psychosis comes from high-income countries in Europe, Australia, Canada and the USA, while these factors are likely to differ under varying sociocultural and economic circumstances. In this study, we aimed to investigate associations of self-stigma, religiosity and perceived social support with symptom severity and psychosocial functioning in an Iranian cohort of people with recent-onset psychosis (i.e. illness duration of <2 years). METHODS: We used baseline data of 361 participants (N = 286 [74%] male, mean age = 34 years [Standard Deviation = 10.0]) from the Iranian Azeri Recent-onset Acute Phase Psychosis Survey (ARAS). We included assessments of self-stigma (Internalized Stigma of Mental Illness, ISMI), religiosity (based on Stark & Glock), perceived social support (Multidimensional Scale of Perceived Social Support, MSPSS), symptom severity (Positive And Negative Syndrome Scale, PANSS) and psychosocial functioning (clinician-rated Global Assessment of Functioning Scale, GAF, and self-reported World Health Organization Disability Assessment Schedule 2.0, WHODAS 2.0). Descriptive analyses were employed to characterize the study sample. Covariate-adjusted ordinal and multivariable linear regression analyses were performed to investigate cross-sectional associations of baseline ISMI, religiosity and MSPSS with concurrent PANSS, GAF and WHODAS 2.0. RESULTS: Higher self-stigma was associated with poorer self-reported functioning (B = 0.375 [95% Confidence Interval (CI): 0.186, 0.564]) and more severe concurrent symptoms (B = 0.436 [95% CI: 0.275, 0.597]). Being more religious was associated with poorer clinician-rated functioning (OR = 0.967 [95% CI: 0.944, 0.991]), but with less severe symptoms (B = -0.258 [95% CI: -0.427, -0.088]). Stronger social support was associated with poorer clinician-rated (OR = 0.956 [95% CI: 0.935, 0.978]) and self-reported functioning (B = 0.337 [95% CI: 0.168, 0.507]). CONCLUSION: This study shows that self-stigma, religiosity and perceived social support were associated with symptom severity and clinician-rated as well as self-reported psychosocial functioning in an Iranian cohort of people with recent-onset psychosis. The findings extend previous evidence on these psychosocial factors to one of the largest countries in the Middle East, and suggest that it may be worthwhile to develop strategies aimed at tackling stigma around psychosis and integrate the role of religiosity and social support in mental ill-health prevention and therapy.

The prevalence of probable overactive bladder and associated risk factors among medical students in Jordan: a cross-sectional study.

BACKGROUND: To discuss the impact of overactive bladder (OAB) on medical students. overactive bladder. is a chronic condition that causes sudden and intense urges to urinate, which can have significant physical and psychological effects on patients' lives. The prevalence of OAB among medical students is relatively high, with some studies reporting rates as high as 35.4%. This research aims to shed light on the prevalence rates and risk factors associated with OAB among medical students in Jordan. METHODS: A cross-sectional study was conducted using an online self-reported questionnaire as the study tool. The questionnaire collected the sociodemographic, health, and academic characteristics of medical students, as well as the new 7-item OABSS score. RESULTS: Out of the total sample of medical students surveyed (n = 525), 44.5% reported experiencing symptoms of OAB. Furthermore, the analysis also revealed that there was a significant difference in the prevalence of OAB between the ages of medical students. In addition, the study also found that there was a significant association between OAB symptoms and basic years, positive history of diagnostic UTI, positive history of recent trauma, high stress, and taking certain medications. CONCLUSIONS: The study highlights the need for further research in this area and emphasizes the possible implications of OAB for medical students, including the need for additional support and resources to manage the condition.

Prevention of Post-Hepatectomy Liver Failure in Cirrhotic Patients Undergoing Minimally Invasive Liver Surgery for HCC: Has the Round Ligament to Be Preserved?

Post-hepatectomy liver failure (PHLF) represents a major cause of morbidity and mortality after liver resection. The factors related to PHLF are represented not only by the volume and function of the future liver remnant but also by the severity of portal hypertension. The aim of this study was to assess whether the preservation of the round ligament (RL) may mitigate portal hypertension, thus decreasing the risk of PHLF and ascites in cirrhotic patients while undergoing minimally invasive liver surgery (MILS). All the cirrhotic patients who underwent MILS for HCC from 2016 to 2021 in two international tertiary referral centers were retrospectively analyzed, comparing cases with the RL preserved vs. those with the RL divided. Only patients with cirrhosis ≥ Child A6, portal hypertension, and ICG-R15 > 10% were included. Main postoperative outcomes were compared, and the risk factors for postoperative ascites (severe PHLF, grade B/C) were investigated through a logistic regression. After the application of the selection criteria, a total of 130 MILS patients were identified, with 86 patients with the RL preserved and 44 with the RL divided. The RL-preserved group showed lower incidences of severe PHLF (7.0% vs. 20.5%, p = 0.023) and ascites (5.8% vs. 18.2%, p = 0.026) in comparison with the RL-divided group. After uni/multivariate analysis, the risk factors related to postoperative ascites were RL division and platelets < 92 × 103/µL, calculated with ROC analysis. The preservation of the round ligament during MILS may mitigate portal hypertension, preventing PHLF and ascites in cirrhotic patients with borderline liver function.

Prognostic accuracy of qSOFA score, SIRS criteria, and EWSs for in-hospital mortality among adult patients presenting with suspected infection to the emergency department (PASSEM) Multicenter prospective external validation cohort study protocol.

BACKGROUND: Early identification of a patient with infection who may develop sepsis is of utmost importance. Unfortunately, this remains elusive because no single clinical measure or test can reflect complex pathophysiological changes in patients with sepsis. However, multiple clinical and laboratory parameters indicate impending sepsis and organ dysfunction. Screening tools using these parameters can help identify the condition, such as SIRS, quick SOFA (qSOFA), National Early Warning Score (NEWS), or Modified Early Warning Score (MEWS). We aim to externally validate qSOFA, SIRS, and NEWS/NEWS2/MEWS for in-hospital mortality among adult patients with suspected infection who presenting to the emergency department. METHODS AND ANALYSIS: PASSEM study is an international prospective external validation cohort study. For 9 months, each participating center will recruit consecutive adult patients who visited the emergency departments with suspected infection and are planned for hospitalization. We will collect patients' demographics, vital signs measured in the triage, initial white blood cell count, and variables required to calculate Charlson Comorbidities Index; and follow patients for 90 days since their inclusion in the study. The primary outcome will be 30-days in-hospital mortality. The secondary outcome will be intensive care unit (ICU) admission, prolonged stay in the ICU (i.e., ≥72 hours), and 30- as well as 90-days all-cause mortality. The study started in December 2021 and planned to enroll 2851 patients to reach 200 in-hospital death. The sample size is adaptive and will be adjusted based on prespecified consecutive interim analyses. DISCUSSION: PASSEM study will be the first international multicenter prospective cohort study that designated to externally validate qSOFA score, SIRS criteria, and EWSs for in-hospital mortality among adult patients with suspected infection presenting to the ED in the Middle East region. STUDY REGISTRATION: The study is registered at ClinicalTrials.gov (NCT05172479).

Differential miRNA expression of hypoxic MCF7 and PANC-1 cells.

Background: Hypoxia plays a critical role in the tumor microenvironment by affecting cellular proliferation, metabolism, apoptosis, DNA repair, and chemoresistance. Since hypoxia provokes a distinct shift of microRNA, it is important to illustrate the relative contribution of each hypoxamiR to cancer progression. Aims: The present study aims to shed light on the hypoxamiRs that are involved in pancreatic and breast cancer progression to highlight novel targets for the development of new therapies. Methods: For 20 cycles, MCF7 breast cancer cells and PANC-1 pancreatic cancer cells were subjected to chronic cyclic hypoxia, which consisted of 72 hours of hypoxia followed by 24 hours of reoxygenation. After 10 and 20 cycles of hypoxia, miRNA expression alterations were profiled using RT-PCR array and further analyzed using a visual analytics platform. The MTT cell proliferation assay was used to determine hypoxic cells' chemoresistance to doxorubicin. Results: Under chronic cyclic hypoxia, hypoxic PANC-1 cells have a comparable doubling time with their normoxic counterparts, whereas hypoxic MCF7 cells show a massive increase in doubling time when compared to their normoxic counterparts. Both hypoxic cell lines developed EMT-like phenotypes as well as doxorubicin resistance. According to the findings of miRNet, 6 and 10 miRNAs were shown to play an important role in enriching six hallmarks of pancreatic cancer in the 10th and 20th cycles of hypoxia, respectively, while 7 and 11 miRNAs were shown to play an important role in enriching the four hallmarks of breast cancer in the 10th and 20th cycles of hypoxia, respectively. Conclusions: miR-221, miR-21, miR-155, and miR-34 were found to be involved in the potentiation of hypoxic PANC-1 hallmarks at both the 10th and 20th cycles, while miR-93, miR-20a, miR-15, and miR-17 were found to be involved in the potentiation of hypoxic MCF7 hallmarks at both the 10th and 20th cycles. This variation in miRNA expression was also connected to the emergence of an EMT-like phenotype, alterations in proliferation rates, and doxorubicin resistance. The chemosensitivity results revealed that chronic cyclic hypoxia is critical in the formation of chemoresistant phenotypes in pancreatic and breast cancer cells. miR-181a and let-7e expression disparities in PANC1, as well as miR-93, miR-34, and miR-27 expression disparities in MCF7, may be associated with the formation of chemoresistant MCF7 and PANC-1 cells following 20 cycles of chronic cyclic hypoxia. Indeed, further research is needed since the particular mechanisms that govern these processes are unknown.

Latest Findings on Minimally Invasive Anatomical Liver Resection.

Minimally invasive liver resection (MILR) is being widely utilized owing to recent advancements in laparoscopic and robot-assisted surgery. There are two main types of liver resection: anatomical (minimally invasive anatomical liver resection (MIALR)) and nonanatomical. MIALR is defined as a minimally invasive liver resection along the respective portal territory. Optimization of the safety and precision of MIALR is the next challenge for hepatobiliary surgeons, and intraoperative indocyanine green (ICG) staining is considered to be of considerable importance in this field. In this article, we present the latest findings on MIALR and laparoscopic anatomical liver resection using ICG at our hospital.

The Association of Corticosteroid Therapy With Mortality and Length of Stay Among Children With Septic Shock: A Retrospective Cohort Study.

Introduction Septic shock remains a leading cause of mortality in pediatric patients. Corticosteroids have been used in the management of sepsis and septic shock, but there is conflicting evidence on the potential benefit of corticosteroid therapy. This study assessed the risk of mortality and length of stay in the pediatric intensive care unit (PICU) among pediatric patients admitted with a septic shock diagnosis. Method A retrospective cohort study was conducted among pediatric patients (up to 14 years old) admitted with a septic shock diagnosis to the PICU of King Abdullah Specialist Children's Hospital in Riyadh from January 2016 to December 2021. The clinical outcomes of patients receiving corticosteroid therapy were compared to those of control patients who were not given corticosteroids. Electronic medical records provided clinical data, severity scores, and the management given for each patient. The patients were followed up from the date of sepsis diagnosis to hospital discharge. Proportional hazard ratios (HRs) were calculated to compare the risk of mortality, length of PICU stay, and length of hospital stay. Results A total of 182 pediatric patients were included in the study, and 86 (47%) received corticosteroid therapy. The median age of the study population was 15 months (interquartile range [IQR]: 2-72 months). Compared to the controls, the patients who received corticosteroids had a higher total Sequential Organ Failure Assessment (SOFA) score (mean±SD: 5.5±3 vs. 7.1±3.3, respectively; p <0.01) and required more ventilation support (72% vs. 28%, respectively) and the use of inotropes and vasopressors (74% vs. 34% and 32% vs. 6%, respectively). In-hospital mortality did not significantly differ between the groups (adjusted HR: 2.66; 95% confidence interval [CI]: 0.66-10.28). Those patients who received corticosteroids had 42% less risk of staying in the PICU for over six days than those not receiving steroids (HR: 0.35; 95% CI: 0.13-0.98) Conclusion After adjusting for baseline characteristics, severity scores, and medical intervention, no association was found between receiving corticosteroids and mortality (p=0.492). Furthermore, patients who received corticosteroids had less risk of a prolonged stay in the PICU than those who did not.

Prenatal maternal stress and the severity of autism spectrum disorder: A cross-sectional study.

Autism spectrum disorder (ASD) is a neurodevelopmental disorder linked to several genetic and environmental factors including antenatal stress. Hence, we aimed to examine whether a mother's stress during pregnancy is associated with the severity of autism spectrum disorder in children. The study was conducted with 459 mothers of children with autism (aged 2-14 years) who were attending rehabilitation and educational centers in the two major cities of Makkah and Jeddah in Saudi Arabia. Environmental factors, consanguinity, and ASD family history were assessed using a validated questionnaire. The Prenatal Life Events Scale questionnaire was used to assess whether the mothers were exposed to stress during pregnancy. Two models of ordinal regression analysis were conducted including gender, child age maternal age, parental age, maternal education, parental education, income nicotine exposure, mother taking medication during pregnancy, family history of ASD, gestation, consanguinity, exposure of prenatal life events (in model 1), and severity of prenatal life events (in model 2). Family history of ASD showed a statistically significant association with the severity of ASD in both regression models (p = .015, odds ratio [OR]: 4.261 in Model 1, and p = .014, OR: 4.901 in model 2). In model 2, the moderate severity prenatal life events showed higher statistically significant adjusted odds ratio for ASD severity compared to no stress (p = .031; OR: 3.82). Within the limitations of this study, prenatal stressors showed some potential contribution to ASD severity. Family history of ASD was the only factor that showed a persistent association with ASD severity. A study that assesses the effect of COVID-19 stress on ASD prevalence and severity is recommended.

Recommendations for Early and Comprehensive Management of Type 2 Diabetes and Its Related Cardio-Renal Complications.

Type 2 diabetes (T2D) is a global health problem accompanied by an elevated risk of complications, the most common being cardiac and renal diseases. In Lebanon, the prevalence of T2D is estimated at 8-13%. Local medical practice generally suffers from clinical inertia, with gaps in the yearly assessment of clinical manifestations and suboptimal screening for major complications. The joint statement presented here, endorsed by five Lebanese scientific medical societies, aims at providing physicians in Lebanon with a tool for early, effective, and comprehensive care of patients with T2D. Findings from major randomized clinical trials of antidiabetic medications with cardio-renal benefits are presented, together with recommendations from international medical societies. Optimal care should be multidisciplinary and should include a multifactorial risk assessment, lifestyle modifications, and a regular evaluation of risks, including the risks for cardiovascular (CV) and renal complications. With international guidelines supporting a shift in T2D management from glucose-lowering agents to disease-modifying drugs, the present statement recommends treatment initiation with metformin, followed by the addition of sodium-glucose cotransporter 2 inhibitors or glucagon-like peptide-1 receptor agonists due to their CV and renal protection properties, whenever possible. In addition to the selection of the most appropriate pharmacological therapy, efforts should be made to provide continuous education to patients about their disease, with the aim to achieve a patient-centered approach and to foster self-management and adherence to the medical plan. Increasing the level of patient engagement is expected to be associated with favorable health outcomes. Finally, this statement recommends setting an achievable individualized management plan and conducting regular follow-ups to monitor the patients' glycemic status and assess their risks every 3-6 months.

Preoperative blood circulation modification prior to pancreaticoduodenectomy in patients with celiac trunk occlusion: Two case reports.

BACKGROUND: Celiac trunk stenosis or occlusion is a common condition observed in patients undergoing pancreaticoduodenectomy (PD). The risk of upper abdominal organ ischemia or failure increases if the blood circulation in the celiac arterial system is not maintained after the surgery. CASE SUMMARY: We present two cases of elderly patients with distal cholangiocarcinoma and celiac trunk occlusion who underwent PD. We performed blood circulation modification preoperatively with transcatheter coil embolization of the arterial arcades of the pancreatic head via the superior mesenteric artery to develop collateral communication between the superior mesenteric artery and the common hepatic or splenic arteries to ensure arterial blood flow to the upper abdominal organs. The postoperative course was marked by delayed gastric emptying, but no major surgical complications, such as biliary or pancreatic fistula, or clinical, biochemical, or radiological evidence of ischemic disease, was observed. CONCLUSION: Preoperative blood circulation modification may be a valid alternative procedure for elderly patients with celiac trunk occlusion who are ineligible for interventional or surgical revascularization.

Is there a therapeutic potential in combining bupropion and naltrexone in schizophrenia?

INTRODUCTION: A sustained-release tablet composed of a combination of the dopamine and norepinephrine reuptake inhibitor bupropion (BUP) and the µ-opioid receptor antagonist naltrexone (NAT) is marketed under the brand name Contrave by Orexigen Therapeutics for appetite control. Minimal literature is available regarding the use of combination bupropion and naltrexone (BUPNAT) in individuals with schizophrenia. AREAS COVERED: In this review, we propose a theoretical model where BUPNAT may have a therapeutic effect in the treatment of schizophrenia. We explore the pathways targeted by the constituent drugs BUP and NAT and summarize the literature on their efficacy and possible adverse effects. We then look at the potential use of BUPNAT in schizophrenia. EXPERT OPINION: Research has hinted that BUP's dopaminergic properties affect the same striatal pathways involved in schizophrenia. NAT, via opioid receptor antagonism, indirectly increases striatal dopamine release by disinhibiting nicotinic acetylcholine receptors. As such, we hypothesize that BUPNAT can have a therapeutic effect in schizophrenia, particularly on negative symptoms. We also suggest that it may ameliorate comorbidities frequently seen in this group of patients, including obesity, smoking, and substance use. Further research and clinical data are needed to elucidate the potential clinical benefits of BUPNAT in the treatment of schizophrenia.

Effects of cyclic acute and chronic hypoxia on the expression levels of metabolism related genes in a pancreatic cancer cell line.

The aim of this study was to characterize cycling hypoxia-induced changes in the expression of metabolism-related genes in the pancreatic cancer cell line PANC1. PANC1 cells were exposed to either 7 h cycles of hypoxia every other day for 20 cycles (cyclic acute hypoxia), or for 72 h cycles of hypoxia once a week for 5 cycles (cyclic chronic hypoxia). Changes in gene expression were profiled using reverse transcription-quantitative PCR and compared to cells cultured under normoxic conditions. Western blotting analysis confirmed upregulation of HIF1-α, glucose-6-phosphate isomerase, and ribokinase at the mRNA level. Upregulation in genes encoding enzymes involved in glycolysis was greater in cells cultured under cyclic acute hypoxia compared with cells cultured under chronic hypoxia including hexokinase2 and phosphoglycerate kinase 1. Genes encoding the pentose phosphate pathway (PPP) enzymes (transketolase and transaldolase) were upregulated to a similar degree. The expression of genes encoding pyruvate dehydrogenases that block pyruvate flow to the TCA cycle was significantly upregulated. Thus, exposure of PANC1 cells to acute hypoxia resulted in the upregulation of genes that shift the metabolism of cells towards glycolysis and the pentose phosphate pathway (PPP) in adaptation to hypoxic stress.

Virtual planning of the anterolateral thigh free flap for heel reconstruction.

PURPOSE: three dimensional (3-D) virtual planning is an example of computer assisted surgery that improved management of composite tissue defects. However, converting the 3-D construct into two dimensional format is challenging. The purpose of this study was to assess 3-D virtual planning of complex heel defects for better optimized reconstruction. PATIENTS AND METHODS: a prospective analysis of 10 patients [9 male and 1 female; mean age = 27.9 years] with post-traumatic heel defects was performed. Heel defects comprised types II (three patients) or III (seven patients) according to Hidalgo and Shaw and were managed using anterolateral thigh (ALT) free flap adopting 3-D virtual planning of the actual defect which was converted into a silicone two dimensional mold. The mean definitive size of the defects was 63.4 cm3 . Functional, aesthetic, and sensory evaluations of both donor and recipient sites were performed 1 year after surgery. RESULTS: Six patients received thinned ALT (mean size = 139 cm3 ) while four patients received musculofasciocutaneous ALT flap (mean size = 199 cm3 ). One flap exhibited partial skin flap necrosis. Another flap was salvaged after re-exploration secondary to venous congestion. The mean follow-up was 20.2 months. The Maryland foot score showed 4 excellent, 5 good, and 1 fair cases. The mean American Orthopedic Foot and Ankle hind foot scoring was 76.3 (range: 69-86). All patients regained their walking capability. CONCLUSIONS: 3-D virtual planning of complex heel defects facilitates covering non-elliptical defects while harvesting a conventional elliptical flap with providing satisfactory functional outcomes and near-normal contour, volume, and sensibility.

Development of a polymeric biomedical device platform with controlled disassembly and in vivo testing in a swine intestinal model.

The aim of this study was to create a surgical guide platform that maintains its integrity while the surgeon performs an intestinal anastomosis or another similar procedure, which then breaks apart and is eliminated from the body in a controlled manner. The device contains mixed polymeric structures that give it a controlled rate of disassembly that could meet the requirements of a specific surgical purpose. The intraluminal anastomotic guide was manufactured as a hollow cylinder composed of layers of porous polyurethane/PCL with polyvinylpyrrolidone as the binding agent similar to a "brick-mortar" architecture. This combination of polymeric structures is a promising manufacturing method from which a variety of tunable devices can be fabricated for specific medical procedures and site-specific indications. The guide was designed to rapidly disassemble within the intestinal lumen after use, reliably degrading while maintaining sufficient mechanical rigidity and stability to support manipulation during complex surgical procedures. The nature of the device's disassembly makes it suitable for use in hollow structures that discharge their contents, resulting in their elimination from the body. A swine model of intestinal anastomosis was utilized to validate the use and function of the device.

High Throughput Study for Molecular Mechanism of Metformin Pre-Diabetic Protection via Microarray Approach.

BACKGROUND: Metformin is a biguanide that exhibits antidiabetic, anticarcinogenic, and anti-inflammatory properties. Despite well-known pancreatic protective effects, metformin's influence on pancreatic islet ß-cell is yet considerably unknown. Protecting the functional insulin-producing ß-cells in the pancreas is a key therapeutic challenge in patients with type 1 (T1DM) or type 2 diabetes mellitus (T2DM). OBJECTIVE: The current study aimed to analyze the protective effects of metformin on streptozocin- induced diabetic rats in T1DM in hepatic tissues. METHODS: In the present study, male Wistar rats (n=24) were randomly assigned into 2 groups (n=12 for each control and test), and metformin (100 mg/kg/day) was given for 7 weeks. Afterward, diabetes was induced by streptozocin (STZ) at a single dose of 150 mg/kg. Blood glucose was examined daily before and after STZ induction. The animals were euthanized by cervical dislocation 5 days after streptozocin injection, after which liver and pancreas were harvested from each rat. RESULTS: The biochemical analyses revealed that metformin resulted in significantly reduced plasma glucose levels and higher pancreatic insulin levels in the test group. Using a restrictive cut-off of at least 2-FC and an adjusted p-value (q-value) of ≤0.05, a sum of 747 genes for the metformin group were shown to be differentially regulated compared to controls (320 Down and 427 Up), by which they were obtained from the liver. Furthermore, the evidence is attained that metformin may hinder the loss of critical ß-cells by reducing inflammatory and apoptosis signaling, promoting fatty acid ß-oxidation, and inducing metabolism. CONCLUSION: Collectively, this study has demonstrated a decrease in blood glucose levels and a rise in insulin-levels and thus consequent prophylactic effects in metformin-given STZ-induced diabetic rats.

Tardive Dyskinesia Following Low-Dose Risperidone.

Tardive dyskinesia is an involuntary athetoid or choreiform movement lasting a minimum of a few weeks. It is associated with the use of neuroleptic medication for at least three months and persists beyond four to eight weeks. Tardive dyskinesia usually occurs as a result of the long-term use of dopamine receptor-blocking agents, mainly first-generation antipsychotics or a high-dose, second-generation antipsychotic. We present a case of a 28-year-old female with osteogenesis imperfecta presented later with major depressive disorder with psychotic features. She was given a low-dose second-generation antipsychotic, namely, risperidone (2 mg) for psychosis for a cumulative duration of three months. As a result, she developed extrapyramidal symptoms in the form of akathisia, axial dystonia, involuntary movement of the right hand, and smacking movement of the lips. Symptoms persisted for more than eight weeks despite discontinuing risperidone and switching to quetiapine. After the exclusion of other differential diagnoses, she was labeled as a case of tardive dyskinesia. More studies are needed to assess whether undiscovered contributing factors to tardive dyskinesia exist and to understand how second-generation antipsychotics (SGAs) contribute to the development of tardive dyskinesia.

A Novel Rank Aggregation-Based Hybrid Multifilter Wrapper Feature Selection Method in Software Defect Prediction.

The high dimensionality of software metric features has long been noted as a data quality problem that affects the performance of software defect prediction (SDP) models. This drawback makes it necessary to apply feature selection (FS) algorithm(s) in SDP processes. FS approaches can be categorized into three types, namely, filter FS (FFS), wrapper FS (WFS), and hybrid FS (HFS). HFS has been established as superior because it combines the strength of both FFS and WFS methods. However, selecting the most appropriate FFS (filter rank selection problem) for HFS is a challenge because the performance of FFS methods depends on the choice of datasets and classifiers. In addition, the local optima stagnation and high computational costs of WFS due to large search spaces are inherited by the HFS method. Therefore, as a solution, this study proposes a novel rank aggregation-based hybrid multifilter wrapper feature selection (RAHMFWFS) method for the selection of relevant and irredundant features from software defect datasets. The proposed RAHMFWFS is divided into two stepwise stages. The first stage involves a rank aggregation-based multifilter feature selection (RMFFS) method that addresses the filter rank selection problem by aggregating individual rank lists from multiple filter methods, using a novel rank aggregation method to generate a single, robust, and non-disjoint rank list. In the second stage, the aggregated ranked features are further preprocessed by an enhanced wrapper feature selection (EWFS) method based on a dynamic reranking strategy that is used to guide the feature subset selection process of the HFS method. This, in turn, reduces the number of evaluation cycles while amplifying or maintaining its prediction performance. The feasibility of the proposed RAHMFWFS was demonstrated on benchmarked software defect datasets with Naïve Bayes and Decision Tree classifiers, based on accuracy, the area under the curve (AUC), and F-measure values. The experimental results showed the effectiveness of RAHMFWFS in addressing filter rank selection and local optima stagnation problems in HFS, as well as the ability to select optimal features from SDP datasets while maintaining or enhancing the performance of SDP models. To conclude, the proposed RAHMFWFS achieved good performance by improving the prediction performances of SDP models across the selected datasets, compared to existing state-of-the-arts HFS methods.

An Adaptive Rank Aggregation-Based Ensemble Multi-Filter Feature Selection Method in Software Defect Prediction.

Feature selection is known to be an applicable solution to address the problem of high dimensionality in software defect prediction (SDP). However, choosing an appropriate filter feature selection (FFS) method that will generate and guarantee optimal features in SDP is an open research issue, known as the filter rank selection problem. As a solution, the combination of multiple filter methods can alleviate the filter rank selection problem. In this study, a novel adaptive rank aggregation-based ensemble multi-filter feature selection (AREMFFS) method is proposed to resolve high dimensionality and filter rank selection problems in SDP. Specifically, the proposed AREMFFS method is based on assessing and combining the strengths of individual FFS methods by aggregating multiple rank lists in the generation and subsequent selection of top-ranked features to be used in the SDP process. The efficacy of the proposed AREMFFS method is evaluated with decision tree (DT) and naïve Bayes (NB) models on defect datasets from different repositories with diverse defect granularities. Findings from the experimental results indicated the superiority of AREMFFS over other baseline FFS methods that were evaluated, existing rank aggregation based multi-filter FS methods, and variants of AREMFFS as developed in this study. That is, the proposed AREMFFS method not only had a superior effect on prediction performances of SDP models but also outperformed baseline FS methods and existing rank aggregation based multi-filter FS methods. Therefore, this study recommends the combination of multiple FFS methods to utilize the strength of respective FFS methods and take advantage of filter-filter relationships in selecting optimal features for SDP processes.