Detection and Diagnosis of Breast Cancer Using an Ensemble Statistical Learning Method

Breast cancer is a malignant tumor that originates in the cells of the breast. It is  the second leading cause of women’s death, after lung cancer. Moreover, the  availability of medical data facilitates the development of related Artificial Intelligence Systems (AIS). The diagnosis (or classification) of breast cancer is a delicate task, which requires efficient and robust classifiers. However,  classical classification methods (in which  a single basic classifier  ( estimator )) are generally confronted with the “bias-variance” dilemma. This, very often, affects seriously their efficiency and robustness. In this article, to mitigate this problem, we propose a new learning model called Triple-Stacking. This technique is composed of three (3) methods of statistical learning (Logistic Regression, Voting and Stacking) and a meta-learner (Decision Stump). The proposed model outperformed the existing ones on two different databases: Breast Cancer Wisconsin Original Data Set and Breast Cancer Wisconsin Diagnostic Data Set, with accuracies of  99.57% and 99.64%, respectively

Short-term forecasting of the prevalence of clinical trachoma: utility of including delayed recovery and tests for infection.

BACKGROUND: The World Health Organization aims to control blinding trachoma by 2020. Decisions on whether to start and stop mass treatments and when to declare that control has been achieved are currently based on clinical examination data generated in population-based surveys. Thresholds are based on the district-level prevalence of trachomatous inflammation-follicular (TF) in children aged 1-9 years. Forecasts of which districts may and may not meet TF control goals by the 2020 target date could affect resource allocation in the next few years. METHODS: We constructed a hidden Markov model fit to the prevalence of two clinical signs of trachoma and PCR data in 24 communities from the recent PRET-Niger trial. The prevalence of TF in children in each community at 36 months was forecast given data from earlier time points. Forecasts were scored by the likelihood of the observed results. We assessed whether use of TF with additional TI and PCR data rather than just the use of TF alone improves forecasts, and separately whether incorporating a delay in TF recovery is beneficial. RESULTS: Including TI and PCR data did not significantly improve forecasts of TF. Forecasts of TF prevalence at 36 months by the model with the delay in TF recovery were significantly better than forecasts by the model without the delay in TF recovery (p = 0.003). A zero-inflated truncated normal observation model was better than a truncated normal observation model, and better than a sensitivity-specificity observation model. CONCLUSION: The results in this study suggest that future studies could consider using just TF data for forecasting, and should include a delay in TF recovery. TRIAL REGISTRATION: Clinicaltrials.gov NCT00792922

A Cluster-Randomized Trial to Assess the Efficacy of Targeting Trachoma Treatment to Children.

Background: The World Health Organization recommends annual treatment of entire trachoma-endemic communities, although children typically have a higher load, longer duration, and greater likelihood of infection. Methods: Forty-eight communities in Matameye, Niger, were randomized to annual oral azithromycin treatment of the entire community or biannual treatment of children aged 0-12 years only. Both children and adults were monitored for ocular chlamydial infection by polymerase chain reaction. Results: The prevalence of childhood infection was reduced in the annually treated arm from 21.2% (95% confidence interval [CI], 15.2%-28.0%) at baseline to 5.8% (95% CI, 3.2%-9.0%) at 36 months (P < .001) and in the biannual arm from 20.2% (95% CI, 15.5%-25.3%) to 3.8% (95% CI, 2.2%-6.0%; P < .001). Adult infection in the annual arm was reduced from 1.7% (95% CI, .9%-2.7%) to 0.3% (95% CI, .0%-.7%) and in the biannual arm from 1.2% (95% CI, .5%-2.2%) to 0.0% (95% CI, .0%-.7%; P = .005). The effect of biannual treatment of children compared with annual treatment of the entire community in both children (95% CI, -.04% to .02%) and adults (95% CI, .9%-2.7%) excluded the prespecified noninferiority threshold of 6% (P = .003 and P < .001, respectively). Conclusions: Periodic distribution of antibiotics to children in trachoma-endemic communities reduces chlamydial infection in both children and untreated adults, suggesting a form of herd protection. Biannual treatment of children was comparable to (specifically, noninferior to) annual treatment of the entire community, and may offer lower antibiotic use and other logistical advantages. Clinical Trials Registration: NCT00792922

Mass Azithromycin and Malaria Parasitemia in Niger: Results from a Community-Randomized Trial.

Studies designed to determine the effects of mass administration of azithromycin on trachoma have suggested that mass azithromycin distributions may also reduce the prevalence of malaria. These studies have typically examined the impact of a small number of treatments over short durations. In this prespecified substudy of a cluster-randomized trial for trachoma, we compared malaria parasitemia prevalence in 24 communities in Niger randomized to receive either annual or biannual mass azithromycin distributions over 3 years. The 12 communities randomized to annual azithromycin received three treatments during the high-transmission season, and the 12 communities randomized to biannual azithromycin received a total of six treatments: three during the high-transmission season and three during the low-transmission season. Blood samples were taken to assess malariometric indices among children in all study communities at a single time point during the high-transmission season after 3 years of the intervention. No significant differences were identified in malaria parasitemia, parasite density, or hemoglobin concentration between the annual and biannual treatment arms. When compared with annual mass azithromycin alone, additional mass azithromycin distributions given during the low-transmission season did not significantly reduce the subsequent prevalence of malaria parasitemia or parasite density after 3 years, as measured during the high-transmission season

Biannual versus annual mass azithromycin distribution and malaria seroepidemiology among preschool children in Niger: a sub-study of a cluster randomized trial.

BACKGROUND: Biannual mass azithromycin administration to preschool children reduces all-cause mortality, but the mechanism for the effect is not understood. Azithromycin has activity against malaria parasites, and malaria is a leading cause of child mortality in the Sahel. The effect of biannual versus annual azithromycin distribution for trachoma control on serological response to merozoite surface protein 1 (MSP-119), a surrogate for malaria incidence, was evaluated among children in Niger. METHODS: Markers of malaria exposure were measured in two arms of a factorial randomized controlled trial designed to evaluate targeted biannual azithromycin distribution to children under 12 years of age compared to annual azithromycin to the entire community for trachoma control (N = 12 communities per arm). Communities were treated for 36 months (6 versus 3 distributions). Dried blood spots were collected at 36 months among children ages 1-5 years, and MSP-119 antibody levels were assessed using a bead-based multiplex assay to measure malaria seroprevalence. RESULTS: Antibody results were available for 991 children. MSP-119 seropositivity was 62.7% in the biannual distribution arm compared to 68.7% in the annual arm (prevalence ratio 0.91, 95% CI 0.83 to 1.00). Mean semi-quantitative antibody levels were lower in the biannual distribution arm compared to the annual arm (mean difference - 0.39, 95% CI - 0.05 to - 0.72). CONCLUSIONS: Targeted biannual azithromycin distribution was associated with lower malaria seroprevalence compared to that in a population that received annual distribution. Trial Registration Clinicaltrials.gov NCT00792922

Childhood Mortality After Mass Distribution of Azithromycin: A Secondary Analysis of the PRET Cluster-randomized Trial in Niger.

BACKGROUND: Mass distributions of azithromycin for trachoma have been associated with secondary benefits, including reductions in child mortality. METHODS: In the Partnership for the Rapid Elimination of Trachoma cluster-randomized trial in Niger, 24 communities were randomized to annual treatment of everyone and 24 communities were randomized to biannual treatment of children under 12 for 3 years (clinicaltrials.gov, NCT00792922). Treatment was a single dose of directly observed oral azithromycin (20 mg/kg up to 1 g in adults). Vital status was assessed during annual census and monitoring visits. In this prespecified secondary analysis, we compared the mortality rate among children 6 months to less than 5 years of age by treatment arm using negative binomial regression. RESULTS: Among children 6 months to less than 5 years of age, 404 deaths occurred during the study period. The mortality rate was 35.6 deaths per 1000 person-years (231 deaths, 95% CI: 30.9-40.9) in the annual arm and 29.0 deaths per 1000 person-years (173 deaths, 95% CI: 24.8-33.8) in the biannual arm. The mortality rate ratio comparing children in the biannual arm to the annual arm was 0.81 (95% CI: 0.66-1.00, P = 0.07; primary outcome). The mortality rate ratio comparing children who died from infectious causes in the biannual arm to the annual arm was 0.73 (95% CI: 0.57-0.94; P = 0.02). No adverse events were reported. CONCLUSIONS: This secondary analysis of a cluster-randomized trial found a nonsignificant 19% decrease in mortality among children 6 months to less than 5 years of age who received biannual azithromycin compared with children who received annual azithromycin. This study was conducted in a high mortality, trachoma-endemic area; thus, results may be specific to this environment only. In addition, the trial was neither designed nor powered to detect a mortality effect, and we cannot rule out the possibility that mortality differences resulted from bias

Comparison of anthropometric indicators to predict mortality in a population-based prospective study of children under 5 years in Niger.

OBJECTIVE: In the present study, we aimed to compare anthropometric indicators as predictors of mortality in a community-based setting. DESIGN: We conducted a population-based longitudinal study nested in a cluster-randomized trial. We assessed weight, height and mid-upper arm circumference (MUAC) on children 12 months after the trial began and used the trial's annual census and monitoring visits to assess mortality over 2 years. SETTING: Niger. PARTICIPANTS: Children aged 6-60 months during the study. RESULTS: Of 1023 children included in the study at baseline, height-for-age Z-score, weight-for-age Z-score, weight-for-height Z-score and MUAC classified 777 (76·0 %), 630 (61·6 %), 131 (12·9 %) and eighty (7·8 %) children as moderately to severely malnourished, respectively. Over the 2-year study period, fifty-eight children (5·7 %) died. MUAC had the greatest AUC (0·68, 95 % CI 0·61, 0·75) and had the strongest association with mortality in this sample (hazard ratio = 2·21, 95 % CI 1·26, 3·89, P = 0·006). CONCLUSIONS: MUAC appears to be a better predictor of mortality than other anthropometric indicators in this community-based, high-malnutrition setting in Niger

Comparison of Mass Azithromycin Coverage Targets of Children in Niger: A Cluster-Randomized Trachoma Trial.

Repeated oral azithromycin distribution targeted only to children has proven effective in reducing the ocular Chlamydia that causes trachoma. Here, we assess whether an enhanced coverage target of at least 90% of children is superior to the World Health Organization recommendation of at least 80%. Twenty-four trachoma-endemic communities in Matamèye, Niger, were randomized to a single day of azithromycin distribution aiming for at least 80% coverage or up to 4 days of treatment and > 90% coverage of children under age 12. All distributions were biannual. Children 15 years were monitored for ocular Chlamydia infection by polymerase chain reaction every 6 months for 36 months in children and at baseline and 36 months in adults. Ocular Chlamydia prevalence in children decreased from 24.9% (95% confidence interval [CI] 15.9-33.8%) to 4.4% (95% CI 0.6-8.2%, P < 0.001) at 36 months in the standard coverage arm and from 15.6% (95% CI 10.0-21.2%) to 3.3% (95% CI 1.0-5.5%; P < 0.001) in the enhanced coverage arm. Enhanced coverage reduced ocular Chlamydia prevalence in children more quickly over time compared with standard (P = 0.04). There was no difference between arms at 36 months in children (2.4% lower with enhanced coverage, 95% CI 7.7-12.5%; P = 0.60). No infection was detected in adults at 36 months. Increasing antibiotic coverage among children from 80% to 90% may yield only short term improvements for trachoma control programs. Targeting treatment to children alone may be sufficient for trachoma control in this setting