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Enhancing AquaCrop model precision for accurate simulation of sweet potato and taro landraces
Get PDFNeglected and underutilised crop species (NUS) such as orange-fleshed sweet potato (OFSP) and taro are nutrient-dense, climate-resilient crops with high potential to diversify food systems. While the AquaCrop model has been calibrated to simulate canopy cover (CC), biomass, and yield for both crops, independent testing across diverse agro-ecological zones is required to critically assess model robustness. We, therefore, evaluated AquaCrop’s ability to simulate the growth and yield of OFSP and taro at three locations in the KwaZulu-Natal province, South Africa. Critical recalibration adjustments included reducing taro’s maximum rooting depth, modifying soil water depletion thresholds to better reflect water stress, and parameterising phenology based on tuber mass stabilisation. Recalibration improved model performance for CC (R
2
, coefficient of determination, up to 0.954 for OFSP; 0.632 for taro), biomass (NSE, Nash-Sutcliffe efficiency, up to 0.975), and final yield (absolute deviations ≤ 6% under optimal irrigation). Validation across three locations confirmed that AquaCrop reliably simulates growth and yield under non-stressed conditions, although performance declined under water-limited environments. The model was run in growing degree-day mode to account for climate variability, which is recommended for future validations. These results demonstrate that, with high-quality calibration datasets representing multiple landraces, AquaCrop can provide reliable yield predictions for NUS. This enables more accurate water management, operational yield predictions, and climate risk assessments for both smallholder and commercial farmers. By bridging the modelling gap for NUS, this work supports their integration into climate adaptation strategies, strengthens food and nutrition security, and promotes resilient agricultural diversification under variable climatic conditions
Behavioral Interventions for Tobacco Cessation in Low- and Middle-Income Countries: A Systematic Review and Meta-analysis.
Get PDFINTRODUCTION: An estimated 78% of the total deaths attributable to smoking tobacco use occurred in low- and middle-income countries (LMICs) in 2019. In addition, smokeless tobacco increases the risk of all-cause mortality, all cancers, including upper aero-digestive tract cancer, stomach cancer, ischemic heart disease and stroke, with 88% of the mortality burden being borne by the South-East Asian region. Evidence-based interventions from high-income countries (HICs) are not easily transferable to LMICs, as patterns of tobacco use, health beliefs associated with tobacco use, and awareness of specific health risks vary substantially.
METHODS: We synthesized the effectiveness of behavioral interventions for tobacco cessation in LMICs through a systematic review and meta-analysis. Interventional studies which delivered individual behavioral intervention and assessed abstinence from tobacco use were included. We examined the pooled intervention effect at 6 months postintervention follow-up.
RESULTS: For continuous abstinence at 6 months, the intervention was superior to the active comparator (RR 2.32; 95% CI 1.78 to 3.02) and usual care (RR 4.39; 95% CI 2.38 to 8.11). For point prevalence abstinence at six months, the intervention was superior to the active comparator (RR 1.76; 95% CI 1.28 to 2.44), and usual care (RR 2.37; 95% CI 1.47 to 3.81). The statistical heterogeneity was substantial to considerable for all comparisons. Only six studies had an overall low risk of bias. Publication bias was observed for all comparisons except for 6-month continuous outcomes.
CONCLUSIONS: Implementation research is needed to understand factors for programme sustainability and equity of the impact of behavioral interventions in reducing tobacco use in LMICs. IMPLICATIONS: Our review is an important step towards understanding the effectiveness of behavior interventions for tobacco cessation suited for LMICs and which are responsive to the contextual needs of such countries
Deep learning in real-time image-guided surgery: a systematic review of applications, methodologies, and clinical relevance
Get PDFAim: Real-time image guidance using deep learning is being increasingly used in surgery. This systematic review aims to characterize intraoperative systems, mapping applications, performance and latency, validation practices, and the reported effects on workflow and patient-relevant outcomes.
Methods: A systematic review was conducted on PubMed, Embase, Scopus, ScienceDirect, IEEE Xplore, Google Scholar, and Directory of Open Access Journals from December 31, 2024. Eligible English-language, peer-reviewed diagnostic accuracy, cohort, quasi-experimental, or randomized studies (2017-2024) evaluated the learning for real-time intraoperative guidance. Two reviewers screened, applied the Joanna Briggs Institute checklists, and extracted the design, modality, architecture, training, validation, performance, and latency. Heterogeneity precluded the meta-analysis.
Results: Twenty-seven studies spanning laparoscopic, neurosurgical, breast, colorectal, cardiac, and other workflows met the criteria. The modalities included red-green-blue laparoscopy or endoscopy, ultrasound, optical coherence tomography, cone-beam computed tomography, and stimulated Raman histology. The architectures were mainly convolutional neural networks with frequent transfer learning. Reported performance was high, with classification accuracy commonly 90%-97% and segmentation Dice or intersection over union up to 0.95 at operating-room-compatible speeds of about 20-300 frames per second or sub-second per-frame latency; volumetric pipelines sometimes required up to 1 min. Several systems demonstrated intraoperative feasibility and high surgeon acceptance, yet fewer than one quarter reported external validation and only a small subset linked outputs to patient-important outcomes.
Conclusion: Deep-learning systems for real-time image guidance exhibit strong technical performance and emerging workflow benefits. Priorities include multicenter prospective evaluations, standardized reporting of latency and external validation, rigorous human factors assessment, and open benchmarking to demonstrate generalizability and patient impact
Going beyond randomised controlled trials to assess treatment effect heterogeneity across target populations.
Get PDFMethods have been developed for transporting evidence from randomised controlled trials (RCTs) to target populations. However, these approaches allow only for differences in characteristics observed in the RCT and real-world data (overt heterogeneity). These approaches do not recognise heterogeneity of treatment effects (HTE) according to unmeasured characteristics (essential heterogeneity). We use a target trial design and apply a local instrumental variable (LIV) approach to electronic health records from the Clinical Practice Research Datalink, and examine both forms of heterogeneity in assessing the comparative effectiveness of two second-line treatments for type 2 diabetes mellitus. We first estimate individualised estimates of HTE across the entire target population defined by applying eligibility criteria from national guidelines (n = 13,240) within an overall target trial framework. We define a subpopulation who meet a published RCT's eligibility criteria ('RCT-eligible', n = 6497), and a subpopulation who do not ('RCT-ineligible', n = 6743). We compare average treatment effects for pre-specified subgroups within the RCT-eligible subpopulation, the RCT-ineligible subpopulation, and within the overall target population. We find differences across these subpopulations in the magnitude of subgroup-level treatment effects, but that the direction of estimated effects is stable. Our results highlight that LIV methods can provide useful evidence about treatment effect heterogeneity including for those subpopulations excluded from RCTs
The impact of sulfadoxine–pyrimethamine resistance on the effectiveness of intermittent preventive treatment for the prevention of malaria in pregnancy in Africa: an updated systematic review and meta-analysis
Get PDFBackground
Resistance of Plasmodium falciparum to sulfadoxine–pyrimethamine threatens the antimalarial effectiveness of intermittent preventive treatment during pregnancy (IPTp) with sulfadoxine–pyrimethamine (ITPp-SP) in sub-Saharan Africa. We updated an aggregated-data meta-analysis to assess the associations between sulfadoxine–pyrimethamine resistance and the effectiveness of IPTp-SP to inform policy.
Methods
We searched databases (Jan 1, 1990, to June 8, 2024) for observational studies or trials reporting data on malaria, low birthweight (<2500 g), anaemia, and other outcomes by IPTp-SP dose and matched these by year and location with studies that reported on molecular markers of sulfadoxine–pyrimethamine resistance. Studies including only women with HIV or combined interventions were excluded. We evaluated how sulfadoxine–pyrimethamine resistance influenced the adjusted risk ratio (aRR) between three and two doses of IPTp-SP for various outcomes using Poisson mixed-effects models that allowed for non-linear relationships. Initially, we performed a threshold analysis, stratified by region, to identify the resistance levels most predictive of altered effect of IPTp-SP doses on malaria parasitaemia at delivery (peripheral or placental parasitaemia by any test), our primary outcome. These resistance strata were then used in all subsequent models for other outcomes. All analyses were adjusted for malaria transmission intensity, HIV infection, percentage of paucigravidae, and insecticide-treated net use. Performance of models was evaluated using cross-validation. The trial was registered with PROSPERO (CRD42021250359).
Findings
Overall, 122 studies involving 148 693 participants were included. For west and central Africa (69 studies comprising 63 745 participants), very low resistance was categorised as a prevalence of the dihydropteroate synthase (dhps) Lys540Glu mutation in the parasite population of less than 4%, and low resistance as a prevalence of Lys540Glu of 4% or higher. In east and southern Africa (53 studies comprising 84 948 participants), moderate resistance was categorised as a prevalence of the Lys540Glu mutation of less than 60% combined with a prevalence of the Ala581Gly mutation of less than 5%, high resistance as a prevalence of Lys540Glu of 60% or higher combined with a prevalence of Ala581Gly of less than 5%, and very high resistance as a prevalence of the Lys540Glu mutation of 60% or higher combined with a prevalence of Ala581Gly of 5% or higher. There was a marked trend towards lower efficacy of IPTp-SP on reducing malaria infection with increasing resistance levels. In west and central Africa, when comparing three versus two doses, the aRR was 0·71 (95% CI 0·65–0·78) in areas with very low resistance and 0·83 (0·72–0·95) in areas with low resistance (p=0·0144 for the difference between dose–response curves in very low vs low resistance). For east and southern Africa, the same trend was observed: the aRR was 0·63 (95% CI 0·57–0·69) in areas with moderate resistance, 0·89 (0·82–0·96) in areas with high resistance, and 0·93 (0·85–1·01) in areas with very high resistance (p<0·0001 for dose–response curves differences between moderate vs high and moderate vs very high resistance). This pattern was not seen for low birthweight. When comparing three versus two doses in west and central Africa, the aRR was 0·58 (95% CI 0·48–0·68) in areas with very low resistance and 0·56 (0·44–0·68) in areas with low resistance (p=0·72 for dose–response curves very low vs low resistance). For east and southern Africa, the aRR was 0·75 (95% CI 0·52–0·98) in areas with moderate resistance, 0·73 (0·69–0·78) in areas with high resistance, and 0·75 (0·63–0·87) in areas with very high resistance (p=0·80 for dose–response curves moderate vs high resistance; p=0·90 for moderate vs very high resistance). Dose comparisons in some resistance strata were limited by sample size.
Interpretation
IPTp-SP antimalarial efficacy is greatly reduced in very high resistance areas. However, it remains effective at reducing low birthweight in these areas, possibly through non-malaria effects on fetal growth. While IPTp-SP use should continue in high SP-resistance areas, alternative malaria preventive strategies are urgently needed in these areas
Exploring Heterogeneity in the Cost-Effectiveness of High-Flow Nasal Cannula Therapy in Acutely Ill Children-Insights From the Step-Up First-line Support for Assistance in Breathing in Children Trial Using a Machine Learning Method.
Get PDFOBJECTIVES: To investigate heterogeneity in the cost-effectiveness of high-flow nasal cannula (HFNC) therapy compared with continuous positive airway pressure (CPAP) for acutely ill children requiring noninvasive respiratory support.
METHODS: Using data from the First-line Support for Assistance in Breathing in Children trial, we explore heterogeneity at the patient and subgroup levels using 2 causal forest approaches and a seemingly unrelated regression approach for comparison. First-line Support for Assistance in Breathing in Children is a noninferiority randomized controlled trial (ISRCTN60048867) involving 24 UK pediatric intensive care units. The Step-up trial focuses on acutely ill children aged 0 to 15 years, requiring noninvasive respiratory support. A total of 600 children were randomly assigned to HFNC and CPAP groups in a 1:1 allocation ratio, with 94 patients excluded because of data unavailability.
RESULTS: The primary outcome is the incremental net monetary benefit (INB) of HFNC compared with CPAP, using a willingness-to-pay threshold of £20 000 per quality-adjusted life year gain. INB is derived from total costs and quality-adjusted life years at 6 months. Subgroup analysis showed that some subgroups, such as male children, those aged less than 12 months, and those without severe respiratory distress at randomization, had more favorable INB results. Patient-level analysis revealed heterogeneity in INB estimates, particularly driven by the cost component, with greater uncertainty for those with higher INBs.
CONCLUSIONS: The estimated overall INB of HFNC is significantly larger for specific patient subgroups, suggesting that the cost-effectiveness of HFNC can be heterogeneous, which highlights the importance of considering patient characteristics in evaluating the cost-effectiveness of HFNC
Potential donor family behaviours, experiences and decisions following implementation of the Organ Donation (Deemed Consent) Act 2019 in England: A qualitative study.
Get PDFBACKGROUND: In May 2020, England implemented "deemed consent" legislation, to make it easier for individuals to donate their organs and convey their decision when alive. Families are supposed to support the decision but can still override it if they disagree. We aimed to learn more about this changed role when families were approached about organ donation.
METHODS: A qualitative study using semi-structured interviews with families, feedback from nurses, comparisons with audit data, and public involvement. We used framework analysis with a health systems perspective and utilitarian theory to explore if the law worked.
FINDINGS: 103 participants were interviewed representing 83 potential donation cases. In 31/83 (37%) cases donation was fully supported, in 41/83 (49%) cases families supported retrieval of some organs, tissues and procedures, and in 11/83 (13%) cases families declined completely. Themes explaining why the law was not (yet) working included: Understanding and agreeing the family's role, confusion about deemed consent, not supporting the deceased expressed decisions, organ donation as too much of a harm, the different experiences of donation pathways, transition from end-of-life to organ donation discussions, experiences of 'consent', paperwork and processes. Families frequently questioned if their relative wanted to have a surgery rather than supporting the person who died to save lives.
CONCLUSION: Families use the unique experience of their relative dying in intensive care to create alternate narratives whereby the outcome satisfies their own utility and not necessarily those of the potential donor. New public ongoing media campaigns crafted to be more supportive of organ donation as a benefit to transplant recipients could help families overcome the many difficulties they encounter at the bedside.
IMPLICATIONS FOR CLINICAL PRACTICE: The soft opt-out policy has not empowered nurses to help families at their most vulnerable to increase their support for and consent to deceased organ donation
Working towards affordable healthy diets: a review on innovations in food price monitoring, policy and research in Australia and beyond.
Get PDFHealthy diets are unaffordable for billions of people worldwide, with food prices rising in high-, middle- and low-income nations in recent times. Despite widespread attention to this issue, recent actions taken to inform policy prioritisation and government responses to high food inflation have not been comprehensively synthesised. Our review summarises (i) innovative efforts to monitor national food and healthy diet price, ii) new policy responses adopted by governments to address food inflation and (iii) future research directions to inform new evidence. Evidence synthesis. Global. None. We describe how timely food and beverage pricing data can provide transparency in the food industry and identify key areas for intervention. However, government policies that improve food affordability are often short-lived and lack sustained commitment. Achieving meaningful impact will require long-term, cross-sectoral actions that are led by governments to support food security, healthy diets and resilient sustainable food systems. This will necessitate a better understanding of how the political economy enables (or hinders) policy implementation, including through coherent problem framing, mitigating conflicts of interest in policymaking, working together as coalitions and developing and utilising evidence on the food security and related impacts of food pricing and affordability policies. Diverse actors must be better equipped with robust data platforms and actionable policy solutions that improve the affordability of healthy and sustainable diets, including by lowering food prices and addressing the broader socio-political determinants of food insecurity
Not intervening as a form of care: Negotiating medical practices at the end-of-life.
Get PDFBiomedicine is organized around interventions. Despite growing concern about overtreatment in healthcare systems, not intervening can still raise questions about potential negligence and the quality of care. Based on ethnographic fieldwork with palliative care teams in England, we explore the work palliative care specialists do to reduce and sometimes halt interventions for patients at the end-of-life, in a general medical environment that is largely interventionist. We describe how judgments about what is an action or not aren't based on obvious or agreed criteria, but ultimately according to what different actors feel constitutes the best form of care. In other words, the underlying values that shape ideas of care determine how action and inaction are nominated, and not the other way around