Distribution-free exponentially weighted moving average control charts for monitoring unknown location

Distribution-free (nonparametric) control charts provide a robust alternative to a data analyst when there is lack of knowledge about the underlying distribution. A two-sided nonparametric Phase II exponentially weighted moving average (EWMA) control chart, based on the exceedance statistics (EWMA-EX), is proposed for detecting a shift in the location parameter of a continuous distribution. The nonparametric EWMA chart combines the advantages of a nonparametric control chart (known and robust in-control performance) with the better shift detection properties of an EWMA chart. Guidance and recommendations are provided for practical implementation of the chart along with illustrative examples. A performance comparison is made with the traditional (normal theory) EWMA chart for subgroup averages and a recently proposed nonparametric EWMA chart based on the Wilcoxon-Mann- Whitney statistics. A summary and some concluding remarks are given.http://www.elsevier.com/locate/csdanf201

Distribution-free exceedance CUSUM control charts for location

Distribution-free (nonparametric) control charts can be useful to the quality practitioner when the underlying distribution is not known. A Phase II nonparametric CUSUM chart based on the exceedance statistics, called the exceedance CUSUM chart, is proposed here for detecting a shift in the unknown location parameter of a continuous distribution. The exceedance statistics can be more efficient than rank-based methods when the underlying distribution is heavy-tailed and/or right-skewed, which may be the case in some applications, particularly with certain lifetime data. Moreover, exceedance statistics can save testing time and resources as they can be applied as soon as a certain order statistic of the reference sample is available. Guidelines and recommendations are provided for the chart’s design parameters along with an illustrative example. The inand out-of-control performance of the chart are studied through extensive simulations on the basis of the average run-length (ARL), the standard deviation of run-length (SDRL), the median run-length (MDRL) and some percentiles of run-length. Further, a comparison with a number of existing control charts, including the parametric CUSUM X chart and a recent nonparametric CUSUM chart based on the Wilcoxon rank-sum statistic, called the rank-sum CUSUM chart, is made. It is seen that the exceedance CUSUM chart performs well in many cases and thus can be a useful alternative chart in practice. A summary and some concluding remarks are given.http://www.tandfonline.com/loi/lssp20hb201

The significance of feeling safe for resilience of adolescents in sub-Saharan Africa

IntroductionAdolescents in sub-Saharan Africa (SSA) are exposed to several challenges and risk factors, linked to historical legacies. Sub-Saharan Africa has one of the highest rates of poverty and inequality in the world, is one of the regions most negatively affected by climate change, performs poorly on many health measures, and has high rates of different forms of violence, especially gender-based violence. These contextual challenges impact adolescent mental health outcomes, preventing them to access resilience-enabling pathways that support positive outcomes despite adversity. This study aimed to contribute to knowledge generation on resilience of young people in the understudied SSA region by investigating which variables directly (or indirectly) affect the resilience of adolescents.MethodsPurposive sampling was used to collect quantitative survey data from 3,312 adolescents (females = 1,818; males = 1,494) between the ages of 12 and 20 years, participating in interventions implemented by a non-governmental organization, the Regional Psychosocial Support Initiative. Data were collected in Angola (385, 11.6%), Eswatini (128, 3.9%), Kenya (390, 11.8%), Lesotho (349, 10.5%), Mozambique (478, 14.4%), Namibia (296, 8.9%), South Africa (771, 23.3%), Uganda (201, 6.1%), and Zambia (314, 9.5%). The survey collected data on socio-demographic status, resilience (CYRM-R), depression (PHQ-9), self-esteem (Rosenberg Self-Esteem Scale) and feelings of safety (self-developed scale). Mental health was defined as lower levels of depression, higher levels of self-esteem and higher levels of feeling safe. A mediation analysis was conducted to investigate the relationship between the predictors (the socio-demographic variables) and the output (resilience), with the mediators being depression, self-esteem and feeling safe (which all link to mental health).ResultsThis study contributes to a gap in knowledge on country-level comparative evidence on significant predictors that impact resilience outcomes (directly or indirectly) for adolescents in sub-Saharan African countries. The results indicate that, when considering all countries collectively, feeling safe is the only predictor that has a significant direct effect on overall resilience and personal resilience, but not on caregiver resilience. When considering each country separately, feeling safe has a direct effect on overall, personal and caregiver resilience for all countries; but not for South Africa and Mozambique.DiscussionThe results provide evidence on which to craft youth development interventions by measuring mediators (depression, self-esteem and feeling safe) and resilience for adolescents in sub-Saharan Africa. The overall results of the present paper point toward a contextually relevant pathway to supporting their resilience, namely, the need to systemically target the creation and/or strengthening of structures that enable adolescents to feel safe

Grade 4 learners with reading and writing difficulties in Mauritius: Oral reading and spelling characteristics

Background: Learners with reading and writing difficulties (RWD) are accommodated in Mauritian government schools without formal curriculum adjustment and teacher support. Little is known about their RWD. The aim was to describe the characteristics of Grade 4 learners with RWD. Aim: To describe the characteristics of Grade 4 learners with RWD. Setting: Government primary schools in Mauritius, in urban and rural areas. Methods: Grade 4 learners with RWD from 20 randomly selected schools were identified with the Screening Tool for Learning Disorders (STLD). A comparative design was used. Parents of 67 learners with RWD (research group [RG]) gave consent. Forty-nine learners without RWD were selected as a control group (CG) based on academic performance and consent. Hearing loss and visual impairment were excluded. The Clinical Evaluation of Language Function Observation Rating Scale (CELF-5 ORS), the Schonell Spelling Test and the Gray Oral Reading Test were used. Results: The CELF-5 ORS showed a wide range of difficulties of the RG with speaking, listening, oral reading and writing. There were significant differences between the RG and CG with reading and spelling. Despite being in Grade 4 (mean age 9.0 years), the mean spelling age for the RG was 5.5 years, corresponding to a Grade 1 level. Positive correlations were found between the STLD and listening, speaking and reading on the CELF-5 ORS for the RG. The more likely it was that participants had specific learning disorders on the STLD, the worse the spelling. Those with a history of speech and language delay performed more poorly with reading and spelling. Conclusion: Difficulties were confirmed by all the measures. Diagnostic assessments for specific learning disorders are required to exclude intellectual disability and other comorbidities. There is a dire need for intervention programs for learners with RWD in mainstream government schools in Mauritius. Programs should include speech-language therapists and aim at prevention, identification, diagnosis and intervention. Contribution: The study is important for speech–language therapists working in the education system and primary school teachers. There is a dire need to implement intervention programs for learners with RWD in mainstream government schools in Mauritius

Satisfaction with hearing assessment feedback using the My Hearing Explained tool : client and audiologist perceptions

OBJECTIVE : To determine the perceived satisfaction and understanding of hearing assessment feedback, using the Ida My Hearing Explained Tool (IMHET), compared to the standard audiogram reported by adult clients and audiologists. DESIGN : This study is a mixed-method design comparing clients and audiologists’ perceptions through a single-blinded, randomised control trial and focus group discussions. After using either the audiogram or IMHET for feedback, clients and audiologists completed the adapted Patient Satisfaction Questionnaire (PSQ). STUDY SAMPLE : During client’s initial audiological consultations, audiologists provided hearing assessment feedback (Total = 51) using the IMHET or audiogram. Twenty-seven clients and seven audiologists participated in focus groups, and/or open-ended questions. RESULTS : Satisfaction was not significantly different (p > 0.05) between the IMHET (76.18; SD: 2.66) or audiogram (75.63; SD: 4.73) for the overall PSQ scores reported by clients and audiologists. Two shared main themes, understanding and satisfaction, were identified for both tools from the focus groups and open-ended questions. A third main theme, recommendations, was identified only for the IMHET. CONCLUSIONS : The IMHET is a valuable resource for clients during hearing assessment feedback. Audiologists recommend that the audiogram be used as a supplement when using the IMHET to provide feedback.https://www.tandfonline.com/loi/iija20hj2023Science, Mathematics and Technology EducationSpeech-Language Pathology and Audiolog

2019 ARIA Care pathways for allergen immunotherapy

Allergen immunotherapy (AIT) is a proven therapeutic option for the treatment of allergic rhinitis and/or asthma. Many guidelines or national practice guidelines have been produced but the evidence-based method varies, many are complex and none propose care pathways. This paper reviews care pathways for AIT using strict criteria and provides simple recommendations that can be used by all stakeholders including healthcare professionals. The decision to prescribe AIT for the patient should be individualized and based on the relevance of the allergens, the persistence of symptoms despite appropriate medications according to guidelines as well as the availability of good-quality and efficacious extracts. Allergen extracts cannot be regarded as generics. Immunotherapy is selected by specialists for stratified patients. There are no currently available validated biomarkers that can predict AIT success. In adolescents and adults, AIT should be reserved for patients with moderate/severe rhinitis or for those with moderate asthma who, despite appropriate pharmacotherapy and adherence, continue to exhibit exacerbations that appear to be related to allergen exposure, except in some specific cases. Immunotherapy may be even more advantageous in patients with multimorbidity. In children, AIT may prevent asthma onset in patients with rhinitis. mHealth tools are promising for the stratification and follow-up of patients.Peer reviewe

Genomic investigations of unexplained acute hepatitis in children

Since its first identification in Scotland, over 1,000 cases of unexplained paediatric hepatitis in children have been reported worldwide, including 278 cases in the UK1. Here we report an investigation of 38 cases, 66 age-matched immunocompetent controls and 21 immunocompromised comparator participants, using a combination of genomic, transcriptomic, proteomic and immunohistochemical methods. We detected high levels of adeno-associated virus 2 (AAV2) DNA in the liver, blood, plasma or stool from 27 of 28 cases. We found low levels of adenovirus (HAdV) and human herpesvirus 6B (HHV-6B) in 23 of 31 and 16 of 23, respectively, of the cases tested. By contrast, AAV2 was infrequently detected and at low titre in the blood or the liver from control children with HAdV, even when profoundly immunosuppressed. AAV2, HAdV and HHV-6 phylogeny excluded the emergence of novel strains in cases. Histological analyses of explanted livers showed enrichment for T cells and B lineage cells. Proteomic comparison of liver tissue from cases and healthy controls identified increased expression of HLA class 2, immunoglobulin variable regions and complement proteins. HAdV and AAV2 proteins were not detected in the livers. Instead, we identified AAV2 DNA complexes reflecting both HAdV-mediated and HHV-6B-mediated replication. We hypothesize that high levels of abnormal AAV2 replication products aided by HAdV and, in severe cases, HHV-6B may have triggered immune-mediated hepatic disease in genetically and immunologically predisposed children

Distribution-free precedence schemes with a generalized runs-rule for monitoring unknown location

Nonparametric statistical process monitoring schemes are robust alternatives to traditional parametric process monitoring schemes, especially when the assumption of normality is invalid or when we do not have enough information about the underlying process distribution. In this paper, we propose to improve the well-known precedence scheme using the 2-of-(h + 1) supplementary runs-rules (where h is a nonzero positive integer). The in-control and out-of-control performances of the proposed control schemes are thoroughly investigated using both Markov chain and simulation based approaches. We find that the proposed schemes outperform their competitors in many cases. A real-life example is given to illustrate the design and implementation of the proposed schemes.https://www.tandfonline.com/loi/lsta202020-05-25hj2019Science, Mathematics and Technology Educatio

Prevalence and associated prenatal and perinatal risk factors for oropharyngeal dysphagia in high-risk neonates in a South African hospital

BACKGROUND: The prevalence of neonatal oropharyngeal dysphagia (OPD) in high-risk infants in lower-middle-income countries is unknown. Objectives: To determine the prevalence and associated risks for OPD in high-risk neonates in order to allow timely intervention for OPD, minimising negative outcomes. METHOD: A prospective cross-sectional observational study was conducted in an urban hospital in South Africa. Clinical feeding assessments were conducted using the Neonatal Feeding Assessment Scale with all available neonates in neonatal care. RESULTS: The sample of 81 high-risk neonates (mean chronological age = 11.7 days; standard deviation = 15.6 days) had been feeding orally for 2 days and were approaching discharge. Fifty-two participants (64.2%) had OPD. Risks likely associated with OPD included breech presentation, septicaemia and other infections, spending more than 1 day on a warm table or incubator, neurological conditions, prenatal exposure to maternal smoking, siblings withmental or neurological disability, participants with congenital disorders, preterm birth (<37 weeks), low birth weight (< 2500 g), or retinopathy of prematurity. CONCLUSION: An unexpected high prevalence of OPD was found in neonates already deemed ready for oral feeding and approaching discharge. Timely early involvement of the Speech-Language Therapists (SLTs) in decision-making about feeding readiness may prevent serious complications of neonatal OPD. Findings may inform South African neonatal clinicians. The study provides motivation for early intervention from SLTs before the infant and mother are discharged from high care and dispersed to communities where intervention services may be scarce.https://sajcd.org.zapm2020Speech-Language Pathology and AudiologyScience, Mathematics and Technology Educatio