Charles R. Newton’s research while affiliated with KEMRI-Wellcome Trust Research Programme and other places

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Publications (99)


Modeling the determinants of attrition in a two-stage epilepsy prevalence survey in Nairobi using machine learning
  • Article
  • Full-text available

June 2025

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175 Reads

Global Epidemiology

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Background Attrition is a challenge in parameter estimation in both longitudinal and multi-stage cross-sectional studies. Here, we examine utility of machine learning to predict attrition and identify associated factors in a two-stage population-based epilepsy prevalence study in Nairobi. Methods All individuals in the Nairobi Urban Health and Demographic Surveillance System (NUHDSS) (Korogocho and Viwandani) were screened for epilepsy in two stages. Attrition was defined as probable epilepsy cases identified at stage-I but who did not attend stage-II (neurologist assessment). Categorical variables were one-hot encoded, class imbalance was addressed using synthetic minority over-sampling technique (SMOTE) and numeric variables were scaled and centered. The dataset was split into training and testing sets (7:3 ratio), and seven machine learning models, including the ensemble Super Learner, were trained. Hyperparameters were tuned using 10-fold cross-validation, and model performance evaluated using metrics like Area under the curve (AUC), accuracy, Brier score and F1 score over 500 bootstrap samples of the test data. Results Random forest (AUC = 0.98, accuracy = 0.95, Brier score = 0.06, and F1 = 0.94), extreme gradient boost (XGB) (AUC = 0.96, accuracy = 0.91, Brier score = 0.08, F1 = 0.90) and support vector machine (SVM) (AUC = 0.93, accuracy = 0.93, Brier score = 0.07, F1 = 0.92) were the best performing models (base learners). Ensemble Super Learner had similarly high performance. Important predictors of attrition included proximity to industrial areas, male gender, employment, education, smaller households, and a history of complex partial seizures. Conclusion These findings can aid researchers plan targeted mobilization for scheduled clinical appointments to improve follow-up rates. These findings will inform development of a web-based algorithm to predict attrition risk and aid in targeted follow-up efforts in similar studies.

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Correction: Evaluating the generalisability of region-naïve machine learning algorithms for the identification of epilepsy in low-resource settings

April 2025

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27 Reads




Figure 2: Achievement of the co-primary outcomes of syndromic diagnosis and microbiological diagnosis (A) Percentage of patients achieving a syndromic diagnosis, per month, pooled across all centres. (B) Percentage of patients achieving a microbiological diagnosis, per month, pooled across all centres. Dots represent percentages of patients achieving a diagnosis in each month of recruitment. The blue line represents the observed trend across these points. The shaded blue around this line represents the 95% CI around these percentages. The dashed red line represents the counterfactual situation: a predicted trend assuming no intervention was delivered, based on pre-intervention data. The shaded red around this line represents the 95% CI around these percentages. The vertical dashed black line represents the timepoint at which the intervention was implemented.
A multifaceted intervention to improve diagnosis and early management of hospitalised patients with suspected acute brain infections in Brazil, India, and Malawi: an international multicentre intervention study

March 2025

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328 Reads

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1 Citation

The Lancet

Background: Brain infections pose substantial challenges in diagnosis and management and carry high mortality and morbidity, especially in low-income and middle-income countries. We aimed to improve the diagnosis and early management of patients admitted to hospital (adults aged 16 years and older and children aged >28 days) with suspected acute brain infections at 13 hospitals in Brazil, India, and Malawi. Methods: With hospital stakeholders, policy makers, and patient and public representatives, we co-designed a multifaceted clinical and laboratory intervention, informed by an evaluation of routine practice. The intervention, tailored for each setting, included a diagnostic and management algorithm, a lumbar puncture pack, a testing panel, and staff training. We used multivariable logistic regression and interrupted time series analysis to compare the coprimary outcomes-the percentage of patients achieving a syndromic diagnosis and the percentage achieving a microbiological diagnosis before and after the intervention. The study was registered at ClinicalTrials.gov (NCT04190303) and is complete. Findings: Between Jan 5, 2021, and Nov 30, 2022, we screened 10 462 patients and enrolled a total of 2233 patients at 13 hospital sites connected to the four study centres in Brazil, India, and Malawi. 1376 (62%) were recruited before the intervention and 857 (38%) were recruited after the intervention. 2154 patients (96%) had assessment of the primary outcome (1330 [62%] patients recruited pre-intervention and 824 [38%] recruited post-intervention). The median age across centres was 23 years (IQR 6-44), with 1276 (59%) being adults aged 16 years or older and 888 (41%) children aged between 29 days and 15 years; 1264 (59%) patients were male and 890 (41%) were female. Data on race and ethnicity were not recorded. 1020 (77%) of 1320 patients received a syndromic diagnosis before the intervention, rising to 701 (86%) of 813 after the intervention (adjusted odds ratio [aOR] 1·81 [95% CI 1·40-2·34]; p<0·0001). A microbiological diagnosis was made in 294 (22%) of 1330 patients pre-intervention, increasing to 250 (30%) of 824 patients post-intervention (aOR 1·46 [95% CI 1·18-1·79]; p=0·00040). Interrupted time series analysis confirmed that these increases exceeded a modest underlying trend of improvement over time. The percentage receiving a lumbar puncture, time to appropriate therapy, and functional outcome also improved. Interpretation: Diagnosis and management of patients with suspected acute brain infections improved following introduction of a simple intervention package across a diverse range of hospitals on three continents. The intervention is now being implemented in other settings as part of the WHO Meningitis Roadmap and encephalitis control initiatives. Funding: UK National Institute for Health and Care Research.


Conceptual model.
Structural equation model of end line quality of life regressed onto the latent constructs of baseline stigma, CMD symptoms and social support.
Structural equation model of end-line functional disability regressed on the latent construct of baseline stigma, CMD symptoms and social support.
Characteristics of participants at T0 (n = 237) and T1 (n = 219; 6 months)
Univariable and multivariable regression analysis of factors associated with a change in quality of life score/change in functional disability between T1 and T0 (6 months)
Impact of co-morbid common mental disorder symptoms in people with epilepsy in Ethiopia on quality of life and functional disability: a cohort study

February 2025

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15 Reads

The objective of this study was to investigate the impact of common mental disorder (CMD; depression/anxiety) symptoms and risky substance use in people with epilepsy in Ethiopia (four districts) on quality of life (QoL) and functioning over 6 months. A prospective cohort study was carried out. Multivariable linear regression followed by structural equation modelling (SEM) was employed. In the multivariable regression model, neither CMD symptoms (β coef. = −0.37, 95% confidence interval [CI] −1.30, +0.55) nor moderate to high risk of alcohol use (β coef. = −0.70, 95% CI −9.20, +7.81) were significantly associated with a change in QoL. In SEM, the summative effect of CMD on QoL was significant (B = −0.27, 95% CI −0.48, −0.056). Change in functional disability was not significantly associated with common mental disorder (CMD) symptoms (β coef. = −0.03, 95% CI −0.48, +0.54) or with moderate to high risk of alcohol use (β coef. = −1.31, 95% CI −5.89, 3.26). In the SEM model, functional disability was predicted by both CMD symptoms (B = 0.24, 95% CI 0.06, 0.41) and seizure frequency (B = 0.67, 95% CI 0.46, 0.87). In this rural Ethiopian setting, co-morbid CMD symptoms and seizure frequency independently predicted functional disability in people with epilepsy.


Evaluating the generalisability of region-naïve machine learning algorithms for the identification of epilepsy in low-resource settings

February 2025

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54 Reads

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2 Citations

Objectives Approximately 80% of people with epilepsy live in low- and middle-income countries (LMICs), where limited resources and stigma hinder accurate diagnosis and treatment. Clinical machine learning models have demonstrated substantial promise in supporting the diagnostic process in LMICs by aiding in preliminary screening and detection of possible epilepsy cases without relying on specialised or trained personnel. How well these models generalise to naïve regions is, however, underexplored. Here, we use a novel approach to assess the suitability and applicability of such clinical tools to aid screening and diagnosis of active convulsive epilepsy in settings beyond their original training contexts. Methods We sourced data from the Study of Epidemiology of Epilepsy in Demographic Sites dataset, which includes demographic information and clinical variables related to diagnosing epilepsy across five sub-Saharan African sites. For each site, we developed a region-specific (single-site) predictive model for epilepsy and assessed its performance at other sites. We then iteratively added sites to a multi-site model and evaluated model performance on the omitted regions. Model performances and parameters were then compared across every permutation of sites. We used a leave-one-site-out cross-validation analysis to assess the impact of incorporating individual site data in the model. Results Single-site clinical models performed well within their own regions, but generally worse when evaluated in other regions (p<0.05). Model weights and optimal thresholds varied markedly across sites. When the models were trained using data from an increasing number of sites, mean internal performance decreased while external performance improved. Conclusions Clinical models for epilepsy diagnosis in LMICs demonstrate characteristic traits of ML models, such as limited generalisability and a trade-off between internal and external performance. The relationship between predictors and model outcomes also varies across sites, suggesting the need to update specific model aspects with local data before broader implementation. Variations are likely to be particular to the cultural context of diagnosis. We recommend developing models adapted to the cultures and contexts of their intended deployment and caution against deploying region- and culture-naïve models without thorough prior evaluation.


Epilepsy in low- to middle-income countries

February 2025

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18 Reads

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2 Citations

Current Opinion in Neurology

Purpose of review Epilepsy disproportionately affects those in low- and middle-income countries (LMICs) where diagnostic and treatment gaps persist. We highlight key recent developments and showcase practical opportunities to improve epilepsy care in resource limited settings. Recent findings In LMICs, cultural, socioeconomic and infrastructural factors drive the epilepsy treatment gap. Robust implementation of the WHO Intersectoral Global Action Plan (WHO IGAP) and Mental Health Gap Action Program (mhGAP), for example, will reduce the epilepsy education gap. Engaging traditional healers and other key community leaders should lessen stigma. The Epilepsy Diagnostic Companion, a culture specific tool that helps identify convulsive seizures, can expedite epilepsy diagnosis at primary care level. Novel, robust 3-D printable EEG headsets prototypes that can be deployed in remote rural communities have been piloted with encouraging results. Levetiracetam has been added to the WHO Essential Medicines List (EML), paving way to safer, less teratogenic antiseizure medications (ASMs). Epilepsy surgery programs in carefully selected patients potentially offer cheap, effective and potentially curative treatments, including in LMICs. Summary Apps, EEG prototypes, better access to ASMs and implementation of WHO iGAP offer current, tangible opportunities to improve epilepsy care in LMICs. Bidirectional learning must be facilitated to also help hard to reach communities in high-income settings.


The ILAE Prioritization Tool development process.
PRISMA‐ScR flow diagram of study selection.
ILAE Prioritization Tool for the development of Clinical Practice Guidelines.
ILAE Prioritization Tool for the development of Consensus‐Based Recommendations.
Prioritizing questions and topics for the development of guidelines and consensus‐based recommendations supported by ILAE: A scoping review and proposal of prioritization criteria

Clinical practice guidelines (CPGs) and consensus‐based recommendations (CBRs) require considerable effort, collaboration, and time—all within the constraints of finite resources. Professional societies, such as the International League Against Epilepsy (ILAE), must prioritize what topics and questions to address. Implementing evidence‐based care remains a crucial challenge in clinical practice. Using rigorous processes to ensure that the best available research evidence informs health care recommendations is of the utmost importance. We aimed to develop a structured and transparent process for prioritizing future CPGs and CBRs supported by the ILAE. A multidisciplinary group of researchers and experts from the ILAE Prioritization Task Force conducted a scoping review to identify prioritization approaches for CPG and CBR development. This scoping review was reported according to the Preferred Reporting Items for Systematic reviews and Meta‐Analyses extension for Scoping Reviews (PRISMA‐ScR) and Cochrane recommendations. A Problem/population, Concept, and Context (PCC) strategy was applied to the literature search and selection of the studies. We searched Medline/PubMed, Embase, Web of Science, and Scopus without time or language limits. The findings were synthesized qualitatively. A consensus‐based process was followed to develop a prioritization scoring tool for CPGs and another for CBRs. Thirty‐nine participants, including clinicians, experts in the field, methodologists, and other relevant stakeholders, contributed to developing the final instrument (based on a 5‐point Likert scale). Of 721 unique citations, 8 papers reporting prioritization approaches for guideline development were included. Based on these, we developed an initial tool with 10 criteria. It was iteratively optimized and revised by the ILAE Standards and Best Practice Council, which unanimously approved the instrument. The ILAE Executive Committee subsequently approved its final version. The ILAE Prioritization Tool is intended to standardize the prioritization processes and optimize the ILAE's use of resources to select CPGs and CBRs for endorsement.


Citations (62)


... stigmatizing views often lead to social rejection, discrimination, and a reluctance among individuals to disclose their diagnosis or seek medical help, thereby hindering timely care and treatment adherence [4,5]. ...

Reference:

Knowledge, Awareness, and Attitudes Toward Epilepsy in Palestine; A Cross-Sectional Study
Epilepsy in low- to middle-income countries
  • Citing Article
  • February 2025

Current Opinion in Neurology

... The use of haram or unclean substances is contrary to Islamic values. Surah Al-An'am verse 145 mentions the prohibition of eating carcasses, blood, and pork, which is also relevant in ensuring the halalness of pharmaceutical ingredients [28]. ...

Understanding the lived experiences of people living with epilepsy: Oral history assessment in the Shai Osudoku and Ningo Prampram districts, Ghana
  • Citing Article
  • December 2024

Epilepsy & Behavior

... In a study on PCMHC in rural Ethiopia, for people living with epilepsy it was recognized through extensive interviews that people's mental health was directly impacted by poverty, stigma, lack of understanding of epilepsy and mental health, family support, religious beliefs and access to care in terms of medication and therapy [10]. In this study, it was clear that by listening to people's stories, involving them in identifying challenges and addressing the interconnected challenges as part of teams involving the person, families, health care providers and communities, better health outcomes could be achieved [18]. ...

Experience and perceptions of mental ill-health in people with epilepsy in rural Ethiopia: A qualitative study

... For example, affective disorders and psychotic symptoms are common in Parkinson's disease, aggravating motor symptoms and complicating treatment [35,36], and post-stroke depression is associated with increased mortality in stroke patients [37]. Also, it was reported that people with epilepsy are significantly more likely to experience psychiatric disorders compared to those without epilepsy [38]. Therefore, there is a stringent need for neurologists to adopt a more holistic approach that incorporates early recognition of psychiatric factors and comprehensive care to their patients [1]. ...

Psychiatric Comorbidities in Persons With Epilepsy Compared With Persons Without Epilepsy: A Systematic Review and Meta-Analysis
  • Citing Article
  • November 2024

JAMA Neurology

... This was explored by Washington-Nortey et al, who found that support groups reduced stress and enhanced empowerment and self-efficacy among carers, as carers could discuss, ask for guidance, and get support from others in these safe spaces. [42] These organizations provided 1 of the few sources of support for many carers, underscoring the need for policies that assist community network establishment and sustainability. ...

Supporting African communities to increase resilience and mental health of kids with developmental disabilities and their caregivers using the World Health Organization’s Caregiver Skills Training Programme (SPARK trial): study protocol for a cluster randomised clinical controlled trial

Trials

... 16 Also, in many clinical studies, the protective effects of ivermectin against OAE were observed. 17,18 Therefore, this study aims to evaluate the efficacy of ivermectin in reducing seizures frequency in patients with OAE undergoing treatment with anti-seizure medications (ASMs). ...

Prevalence of onchocerciasis and epilepsy in a Tanzanian region after a prolonged community-directed treatment with ivermectin

... The pandemic brought new challenges for PWE worldwide, making it harder to access healthcare facilities and ASMs. 11,12 As a result, PWE could have experienced an These patients had lower HADS-A and HADS-D scores, with a statistically significant p-value of 0.0001. ...

The impact of COVID‐19 on people with epilepsy: Global results from the coronavirus and epilepsy study

... Primary care health personnel are often the first point of contact for families seeking help with children's mental health problems. If these professionals hold stigmatizing perceptions, they may underestimate or dismiss symptoms, potentially delaying diagnosis and access to appropriate, quality treatment (Mkubwa et al., 2024). Having this measurement tool meets the need for a clearer understanding of the stigmatization processes children and young people are subjected to by health personnel. ...

Knowledge, attitudes, and practices on child and adolescent mental health among healthcare workers in sub-Saharan Africa: a scoping review

International Journal of Mental Health Systems

... Leave-one-out sensitivity analysis. Depression frequently occurs alongside epilepsy and affects the HRQoL of many patients (49). In this meta-analysis, depression (β = −4.591, ...

Multipsychiatric Comorbidity in People With Epilepsy Compared With People Without Epilepsy: A Systematic Review and Meta-analysis
  • Citing Article
  • July 2024

Neurology

... Notably, approximately one-fifth of the cases exhibited only nonconvulsive seizures [18]. The diagnostic difficulties for nonconvulsive epilepsy have also been reported in a recent study performed in Kenya [19]. ...

Prevalence of all epilepsies in urban informal settlements in Nairobi, Kenya: a two-stage population-based study

The Lancet Global Health