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Abstract

Background: Fluctuating hearing loss is characteristic of Ménière’s disease (MD) during acute episodes. However, no reliable audiometric hallmarks are available for counselling the hearing recovery possibility.

Aims/objectives: To find parameters for predicting MD hearing outcomes.

Material and methods: We applied machine learning techniques to analyse transient-evoked otoacoustic emission (TEOAE) signals recorded from patients with MD. Thirty unilateral MD patients were recruited prospectively after onset of acute cochleo-vestibular symptoms. Serial TEOAE and pure-tone audiogram (PTA) data were recorded longitudinally. Denoised TEOAE signals were projected onto the three most prominent principal directions through a linear transformation. Binary classification was performed using a support vector machine (SVM). TEOAE signal parameters, including signal energy and group delay, were compared between improved (PTA improvement: ≥15?dB) and nonimproved groups using Welch’s t-test.

Results: Signal energy did not differ (p?=?.64) but a significant difference in 1-kHz (p?=?.045) group delay was recorded between improved and nonimproved groups. The SVM achieved a cross-validated accuracy of >80% in predicting hearing outcomes.

Conclusions and significance: This study revealed that baseline TEOAE parameters obtained during acute MD episodes, when processed through machine learning technology, may provide information on outer hair cell function to predict hearing recovery.  相似文献   
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Introduction

Malignant pleural mesothelioma (MPM) is an uncommon cancer with a poor prognosis and heterogeneous survival. Surgery for MPM is offered in some specialist centers to highly selected patients. A previously described classification and regression tree (CART) model stratified survival in unselected MPM patients using routinely collected clinical data. This study aimed to examine the performance of this CART model on a highly selected surgical population.

Methods

Data were collected from subjects undergoing cytoreductive surgery for MPM from specialist centers in Hyõgo, Japan, and Sydney, Australia, between 1991 and 2016. The CART model was applied using the combination of clinical variables to stratify subjects into risk groups (1 through 4); survival characteristics were then compared.

Results

Two hundred eighty-nine cases were included (205 from Australia, 84 from Japan). Overall median survival was 34.6 (interquartile range: 17.5–56.1) months; median age was 63.0 (interquartile range: 57.0–67.8) years, and 83.0% (n = 240) were male. There were no clinically meaningful differences between the two cohorts. Survival across the four risk groups was significantly different (p < 0.0001); the model stratified survival well with a Harrell's concordance statistic of 0.62 (95% confidence interval: 0.57–0.66) at 36 months. The group with the longest survival (median, 82.5 months) had: no weight loss, hemoglobin > 153 g/L and serum albumin > 43 g/L at time of referral to the surgical center.

Conclusions

Using routinely available clinical variables, the CART model was able to stratify surgical patients into risk groups with statistically different survival characteristics with fair to good performance. Presence of weight loss, anemia, and low albumin should confer caution when considering surgical therapy for MPM.  相似文献   
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BACKGROUND

Our objective was to examine the association between school wellness committees and implementation of nutrition wellness policies and children's weight status and obesity‐related dietary outcomes.

METHODS

A cross‐sectional study was conducted of 4790 children aged 4‐15 years recruited from 130 communities in the Healthy Communities Study. Multilevel statistical models assessed associations between school wellness policies and anthropometric (body mass index z‐score [BMIz]) and nutrition measures, adjusting for child and community‐level covariates.

RESULTS

Children had lower BMI z‐scores (?0.11, 95% confidence interval [CI]: ?0.19, ?0.03) and ate breakfast more frequently (0.14 days/week, 95% CI: 0.02‐0.25) if attending a school with a wellness committee that met once or more in the past year compared to attending a school with a wellness committee that did not meet/did not exist. Children had lower added sugar (p < .0001), lower energy‐dense foods (p = .0004), lower sugar intake from sugar‐sweetened beverages (p = .0002), and lower dairy consumption (p = .001) if attending a school with similar or stronger implementation of the nutrition components of the school wellness policies compared to other schools in the district.

CONCLUSIONS

A more active wellness committee was associated with lower BMI z‐scores in US schoolchildren. Active school engagement in wellness policy implementation appears to play a positive role in efforts to reduce childhood obesity.
  相似文献   
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