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PubMed2026

Isometric Exercises for Tendinopathies: A Systematic Literature Review.

PURPOSE: Musculoskeletal disorders are among the most common reasons for medical consultation, with tendinopathies accounting for up to 30% of such presentations. Although exercise remains the cornerstone of management, the most effective modality continues to be debated. Eccentric exercise has long been the mainstay, but the role of isometric exercise in pain modulation and functional recovery remains unclear. This systematic review aims to evaluate the current evidence on the efficacy of isometric exercises in the management of tendinopathies across various anatomic sites. METHODS: A systematic search was conducted in PubMed, MEDLINE, Embase, and the Cochrane Library from inception to August 1, 2025. Eligible studies included randomized controlled trials and prospective or retrospective cohort studies assessing isometric exercise interventions for tendinopathy, with or without comparator groups. Case series and case reports were excluded. Data extracted included participant demographic characteristics, site of tendinopathy, symptom duration, treatment duration, adherence, and outcome measures such as Victorian Institute of Sports Assessment (A, P, or G), visual analog scale, Patient-Specific Functional Scale, 36 item short form health survey (SF-36), and EuroQol 5-Dimension questionnaires. Imaging outcomes (ultrasound or magnetic resonance imaging) were recorded where available. Methodological quality and risk of bias were assessed using the Cochrane Risk of Bias tool in accordance with Preferred Reporting Items for Systematic Reviews and Meta-Analysis guidelines. FINDINGS: The search identified 304 articles, of which 13 randomized controlled trials met the inclusion criteria, encompassing 336 participants (40% female). Tendinopathy sites included the patellar (n = 4), Achilles (n = 3), lateral elbow (n = 2), rotator cuff (n = 2), wrist extensor (n = 1), and gluteal (n = 1) tendons. Median symptom duration was 23 months (interquartile range, 3-51 months). Intervention periods ranged from a single 45-minute session to 4-month exercise programs. Treatment adherence was high initially (nearly 100%) but declined over time, with 70% of participants in the isometric and 58% in the control (isotonic) groups completing ≥80% of sessions. Pain reduction and functional improvement were statistically significant in only 3 studies. Imaging-based outcomes were inconsistently reported, and study heterogeneity precluded meta-analysis. Overall methodological quality was rated as good in 3 studies and poor in 10. IMPLICATIONS: Current evidence provides limited support for the superiority of isometric exercise in tendinopathy management. Although isometric regimens appear tolerable and may confer short-term analgesic benefits, their long-term efficacy relative to eccentric or isotonic protocols remains uncertain. Future research should prioritize standardized outcome measures, longer follow-up, and uniform diagnostic criteria to strengthen the evidence base for exercise prescription in tendinopathies.

Humans↗

PubMed2026

Redefining the real problem in psychedelic trials: Why fighting the Lessebo matters more than blinding integrity.

Imperfect blinding is not specific to psychedelic trials. In randomized trials, treatment allocation is frequently correctly guessed, yet blinding integrity is rarely assessed outside of psychedelic research and is generally not considered a barrier in regulatory evaluation. The intense debate in psychedelics may reflect a broader double standard affecting mental health research, when uncertainties arising from imperfect blinding are confounded by those linked to patient-reported outcome measures. Indeed, people living with mental disorders are often viewed as unreliable reporters, despite well-documented limitations of clinician-rated scales and the absence of robust biological markers of symptomatic change. Importantly, it is the maintenance of reasonable doubt of treatment allocation that sustains internal validity and ethical feasibility of placebo-controlled designs, rather than perfect blinding. Concerns about expectancy bias in psychedelic trials are closely tied to blinding debates. When allocation is inferred, expectations may cluster in the arm perceived as active or in stereotyped experiences and influence outcomes differently in active and control arms, leading to a risk of lessebo, a negative placebo effect due to the negative expectation related to receiving a placebo. However, we argue that an underrecognized mechanism of lessebo is disappointment. This risk may reflect insufficient clinical management of disappointment rather than pre-treatment expectation alone. We therefore propose shifting the emphasis from preserving inevitably imperfect blinding towards mitigating disappointment in both arms. Establishing non-stereotyped expectations prior to treatment through structured psychoeducation, strengthened therapeutic alliance, and realistic preparation would help avoid lessebo effects. Such strategies would enhance ethical rigor, interpretability, and the clinical usefulness of psychedelic trials.

Humans↗

PubMed2026

Improving insurance deduction identification: a hybrid artificial intelligence model using machine learning and expert systems.

PURPOSE: Financial challenges in healthcare systems worldwide, especially in low- and middle-income countries like Iran, have increased hospitals' reliance on insurance reimbursements. Unrecognized insurance deductions often cause severe financial shortages, making efficient deduction management crucial. This study aimed to design a hybrid intelligent system for identifying and predicting insurance deductions by combining machine learning and expert system frameworks. DESIGN/METHODOLOGY/APPROACH: A mixed-methods design was applied in four stages. First, a scoping review identified the causes and patterns of insurance deductions. Second, interviews with 15 insurance experts produced a validated checklist and a dataset from inpatient billing records. Third, using the CRISP-DM methodology, machine learning algorithms were developed and tested in SPSS Modeler alongside a fuzzy expert system developed in MATLAB. Finally, the model was validated using the holdout method. FINDINGS: Four categories of deduction drivers were identified: service provision, registration errors, document submission issues, and revenue conversion processes. The CHAID decision tree outperformed other algorithms with a 99% precision rate and the lowest Mean Absolute Error (9.43). A brief assessment of potential overfitting was conducted to ensure that the CHAID model's high accuracy was interpreted cautiously and supported by the validation results. The fuzzy expert system with validated rules was adaptable for deduction classification, especially for cases unsuitable for quantitative modeling. ORIGINALITY/VALUE: The hybrid model improves detection and prevention of deductions, offering actionable insights for hospital administrators, insurers, and policymakers. Its implementation can enhance hospital information systems, streamline claims processing, and optimize revenue management amid financial constraints.

Machine Learning↗

PubMed2026

Stroke risk following BNT162b2 vaccination: a systematic review and meta-analysis of self-controlled case series studies.

INTRODUCTION: Whether BNT162b2 (Pfizer-BioNTech) vaccination increases stroke risk remains a public health concern. This is the first meta-analysis to synthesize self-controlled case series (SCCS)-derived stroke risk estimates specifically for BNT162b2 vaccination. METHODS: PubMed and Embase were searched from inception through 9 May 2026, following PRISMA 2020 guidelines. Eight eligible SCCS studies were pooled using a random-effects model with restricted maximum likelihood (REML) estimation and the Knapp-Hartung adjustment. RESULTS: Eight studies across six countries encompassing several million vaccinated individuals were included. The pooled incidence rate ratio (IRR) was 0.967 (95% CI 0.892-1.049; I2 = 69.2%), indicating no statistically significant increase in stroke risk. Subgroup analyses showed no evidence of effect modification across continent, risk-window length, dose category, SCCS variant, or age group. CONCLUSIONS: These findings provide no evidence of increased short-term stroke risk following BNT162b2 vaccination at the population level. The observed heterogeneity appeared to be partly driven by methodological differences rather than true biological variation in vaccine effect.

Humans↗

PubMed2026

Digital health interventions for diabetes management in the eastern mediterranean region: A systematic review of types and effectiveness.

AIM: The aim of this study was to systematically review and evaluate the types and effectiveness of digital health interventions used for diabetes management in the Eastern Mediterranean Region (EMRO). METHODS: This systematic review, conducted according to PRISMA guidelines, searched PubMed, Web of Science, and Scopus up to May 2025 to identify studies on digital interventions for diabetes management in EMRO countries. Methodological quality of the included studies was evaluated using the EPHPP tool, and findings were categorized by intervention type, outcome measures, and intervention effectiveness. RESULTS: A total of 46 studies were included, mainly from Iran and Saudi Arabia. Phone calls and SMS were the most common digital tools. Digital interventions significantly improved HbA1c, fasting blood sugar, and several behavioral outcomes such as physical activity, medication adherence, and self-efficacy, while effects on psychological outcomes were mixed. CONCLUSION: Digital health interventions, especially phone calls and SMS, effectively improve glycemic control and self-care behaviors, though their impact on psychological outcomes remains inconsistent.

Humans↗

PubMed2026

Meta-analysis of source identification and apportionment in soil: A systematic review of analytical procedures, receptor modeling, and environmental applications.

Soil pollution poses significant risks to ecosystems and human health, necessitating accurate source identification and apportionment to guide mitigation strategies. This systematic review evaluates the application of Positive Matrix Factorization (PMF) and other receptor models in soil pollution studies, focusing on analytical procedures, tracer indicators, and environmental applications. This review aims to provide a comprehensive framework for conducting soil source apportionment studies, aiding policymakers in designing effective, region-specific environmental management strategies by compiling global trends and methodological insights. The study addresses sampling protocols, emphasizing representativeness and quality control. Data from 500 peer-reviewed publications highlight the dominance of research in China, Eastern Europe, and South Asia, with agricultural soils being the most frequently studied. Key findings reveal that traffic emissions (20.8 %) and industrial activities (19.4 %) are the primary global contributors to soil contamination, with regional variations such as coal combustion in cold climates and agricultural inputs in developing regions. Policy recommendations include stricter industrial regulations, sustainable agricultural practices, and targeted remediation efforts based on source-specific risks.

Soil Pollutants↗

PubMed2026

The interplay between circadian misalignment or sleep disturbances and cognition and brain function in individuals with different degrees of insulin resistance - a systematic review.

Disruption of sleep increases the risk of type 2 diabetes and worsens cognitive outcomes, yet few studies have evaluated the interaction between insulin resistance and sleep parameters in relation to cognitive outcomes or the risk of dementia. This systematic review examines how circadian misalignment and sleep disturbances affect cognition and neuroimaging findings in individuals with varying degrees of insulin resistance. Across 27 studies, disrupted circadian rhythmicity and sleep disturbances were negatively associated with brain health, possibly through its effects on insulin sensitivity, whereas the impact of sleep duration and quality were inconclusive. Methodological heterogeneity, reliance on cross-sectional designs, and limited control for confounders restricted definitive conclusions and highlighted the need for longitudinal and interventional studies with objective measurements. Nonetheless, the findings support circadian rhythmicity as a potentially modifiable risk factor for preserving cognition in insulin-resistant populations. Future research should prioritise prospective and interventional studies and focus on biological markers rather than self-reported outcomes.

Humans↗

PubMed2025

Exploring determinants of vaccine hesitancy among healthcare professionals: a systematic literature review.

INTRODUCTION: This systematic review aims to assess determinants of vaccine hesitancy (VH) among healthcare professionals, to identify knowledge gaps and inform targeted training programs. RESEARCH DESIGN AND METHODS: A systematic search of PubMed and Scopus was conducted in February 2024. PRISMA criteria were applied, and methodological quality was assessed using a cross-sectional study evaluation tool. Studies addressing HCWs' VH determinants, including knowledge, attitudes, communication, and organizational factors, were included. RESULTS: Out of 1394 records, 221 articles were included. Reported prevalence of VH among HCWs varied across studies, reflecting differences in professional roles, settings, and vaccines studied. Key determinants included gaps in knowledge, personal beliefs, organizational barriers, and communication skills. The review highlights the importance of evidence-based information, continuing education, and effective communication in addressing VH among HCWs. CONCLUSIONS: Educational and organizational interventions are essential to improve HCWs' knowledge, attitudes, and practices regarding vaccination. Strengthening vaccine education, fostering effective communication, and addressing organizational challenges can reduce hesitancy and support HCWs in promoting vaccination among patients. Future initiatives should consider the diversity of educational settings, professional roles, and training requirements across healthcare systems.

Humans↗

PubMed2026

Hot vs cold knife for endoscopic ablation of posterior urethral valves: a systematic review by the EAU-YAU paediatric urology working group.

INTRODUCTION: Posterior urethral valves (PUV) are the most frequent cause of congenital lower urinary tract obstruction in males. Despite early surgical ablation, up to 22% of patients develop chronic kidney disease and 11% progress to end-stage renal disease. Multiple endoscopic modalities have been described for valve ablation but the optimal technique remains uncertain. This systematic review aims to determine whether cold or hot knife ablation provides superior effectiveness for primary endoscopic treatment of PUV in a single surgical session. MATERIAL AND METHODS: A systematic search of PubMed and Embase databases was conducted to identify studies comparing cold and hot knife techniques for endoscopic ablation of PUV in children, covering all publications up to December 2025. The review was performed in accordance with PRISMA 2020 guidelines and was prospectively registered in PROSPERO (ID CRD420251180556). Original studies including patients <18 years who underwent primary valve ablation with postoperative cystoscopy or VCUG and ≥6 months of follow-up were included. Quality assessment was done using RoB 2.0 for randomized trials and MINORS for observational studies. RESULTS: A total of 1581 studies were identified, of which 26 met the inclusion criteria, comprising one randomized controlled trial, five prospective, and 20 retrospective studies constituting a sum of 1725 paediatric patients. The overall methodological quality of included studies was moderate, with marked heterogeneity in design, follow-up duration, and outcome reporting, limiting direct comparisons across series. Thus statistical analysis was not possible. Of these, 829 (48.1%) underwent cold valve ablation and 896 (51.9%) underwent hot ablation techniques. Within the cold group, most patients were treated with a cold knife (80.2%), followed by balloon dilatation (7%), the Mohan valvotome (6.5%), cold hook (5%), and, rarely, a modified venous valvulotome (1.3%). Among hot techniques, 32.8% of procedures were performed by electro-fulguration with a resectoscope, 29.4% using a Bugbee electrode, 23.8% with a hook electrode and 14% with laser-based systems. Follow-up ranged from 6 months to 22 years across studies. Single-session success rates for valve ablation ranged from 22% to 100% in the cold resection group and from 71.4% to 100% in the hot resection group. Reintervention for residual valves was reported in 0%-78% of cold cases and in 0%-28.6% of hot resections. Urethral stricture rates ranged from 0% to 11.1% after cold incision and from 0% to 23.8% after hot techniques. Reporting of postoperative outcomes such as urinary tract infection, incontinence, bladder dysfunction, vesicoureteral reflux (VUR) resolution, hydronephrosis improvement, and renal function varied widely among studies and was assessed using different methodologies. CONCLUSIONS: Both cold and hot ablation techniques for PUV achieved high single-session success rates and low complication rates. Cold resection appeared slightly safer, although this finding should be interpreted cautiously given the heterogeneity and observational nature of the available data.

Humans↗

PubMed2026

External load metrics and monitoring in women's football match play: A systematic review.

This systematic review aimed to identify the most commonly used variables for monitoring external load during elite women's football matches and to compare reporting practices internationally and in Brazil. Searches were conducted in Web of Science, PubMed, and SciELO using the PICOS framework between February and March 2026, resulting in the inclusion of 35 studies. The main outcomes analysed were total distance covered (TD), distance covered across speed zones (HSR, VHSR, sprint), number of accelerations and decelerations, and maximum speed. TD and distance covered across speed zones were the most frequently reported indicators (94.3%), followed by HSR (82.8%) and sprint distance (68.5%). Considerable variability was observed in the classification of speed zones and thresholds used to define accelerations and decelerations, limiting comparisons between studies. External load values varied according to playing position and competition level, with international matches generally imposing greater demands than national competitions. Brazilian research remains limited and demonstrates notable methodological variability. This review proposes standardised speed and acceleration/deceleration thresholds based on the most recurrent ranges reported in the literature, supporting improved consistency in monitoring practices across elite women's football contexts.

Humans↗

PubMed2026

School-based sexual violence prevention: A systematic review.

PURPOSE: Sexual violence profoundly affects the health and development of children, adolescents, and young adults, representing a persistent challenge to public policy. This systematic review examined the effectiveness of school-based interventions aimed at prevention. METHODS: Eighteen randomized controlled trials published between 2012 and 2024 were retrieved from four major databases. The programs were implemented in primary, secondary, and higher education settings and targeted children, adolescents, and young adults. RESULTS: The results revealed improvements in knowledge and attitude, particularly regarding consent and awareness, whereas evidence supporting behavioral changes was less frequent and often limited. Methodological limitations, such as short follow-up periods and participant attrition, restricted the assessment of long-term outcomes. CONCLUSIONS: This review highlights the importance of multicomponent, participatory, and culturally sensitive approaches, along with the integration of digital tools and continuous evaluation systems, to strengthen the role of schools as safe and transformative spaces in the prevention of sexual violence. IMPLICATIONS AND CONTRIBUTIONS: This systematic review suggests that school-based interventions hold significant potential for the prevention of sexual violence. It identifies promising strategies and reinforces the importance of culturally sensitive, sustained, evidence-based approaches to ensure learning environments that are safe, protective, and promotive of gender equity.

Humans↗

PubMed2026

Identifying and Prioritizing Core Components of Relationship Education Programs: a Case Study of an Artificial Intelligence (AI) Assisted Systematic Review.

The field of prevention science seeks to identify and implement effective strategies to address social, emotional, and health challenges. A critical aspect of this endeavor is determining the core components of prevention programs that drive positive outcomes. This article presents a case study utilizing artificial intelligence (AI)-assisted systematic review methods to identify key components of healthy marriage and relationship education programs. Given the growing body of research in this domain, AI tools offer a promising means to enhance the efficiency and accuracy of literature reviews. This study employed AI to screen, code, and validate research articles, demonstrating its effectiveness in expediting systematic reviews while maintaining high accuracy in inclusion screening. This case study involved a systematic review of 22,028 resources (identified from PsycINFO, Academic Search Ultimate, and Google) and a final data set of 268 relevant studies. AI screening was integral in effectively conducting multiple rounds of screening. However, findings also highlight challenges in AI-assisted qualitative data abstraction, underscoring the continued need for human expertise in complex coding tasks. The study contributes to the ongoing discourse on integrating AI into prevention science methodologies and offers insights for optimizing AI applications in systematic reviews.

Artificial Intelligence↗

PubMed2025

Psychological interventions for children with chronic physical conditions: a systematic review assessing the role of coping, emotional and cognitive processes.

OBJECTIVES: Coping, emotional and cognitive processes are crucial in child development, particularly in children with pediatric chronic physical conditions (CPC). No systematic review in pediatric psychology has investigated the effectiveness of interventions on these processes concurrently. This review addresses this gap by focusing on the effectiveness of psychological interventions on coping, emotional and cognitive processes in children with CPCs. METHODS: Five electronic databases were searched for studies assessing at least one of these processes. Only randomized-controlled trials with children (8-12 years) with a CPC (e.g. diabetes, asthma), which implemented a psychological intervention were included. This study is registered in (CRD42021233505). RESULTS: Ten intervention studies were identified. While cognitive interventions (Cogmed) showed some improvements in working memory, the effects varied across studies despite similar methodologies. Coping interventions (e.g. Coping Skills Training) showed little effect on coping strategies or psychological health variables and were no more beneficial than control groups. No study trained coping, emotional processes and cognitive processes together. CONCLUSION: This review shows current limitations in evaluating psychological interventions targeting coping, cognitive or emotional processes in children with CPCs, limiting a comprehensive understanding of the interventions' action mechanisms. Systematically including underlying processes in intervention studies could help to better adjust those interventions.

Humans↗

PubMed2026

Instruments for measuring body image in breast cancer patients: a systematic review of measurement properties.

PURPOSE: To evaluate the psychometric properties of PROMs for measuring body image in breast cancer patients. METHODS: In December 2024, a psychometric systematic review was performed in the nine databases. The COSMIN checklist was employed to evaluate the methodological quality and psychometric properties of the included body image measures. The level of evidence was assessed using the GRADE framework, and final recommendations were formulated for the scale. RESULTS: Thirty-eight articles evaluating fifteen PROMs were included in this review. Structural validity, internal consistency, and hypothesis testing had been most frequently evaluated. Measurement error had not been assessed for all PROMs. Twelve instruments show potential application value but require further research. The BAS-BC, PSPP, and ASI-R are not recommended for use, as these instruments do not meet the strict COSMIN thresholds for full recommendation. CONCLUSION: The BIS can be recommended as a temporary screening tool for assessing body image outcome in clinical practice. The BIRS can be tentatively advised for measuring specific postoperative body image changes. However, further comprehensive studies are required to validate the psychometric properties of existing PROMs.

Female↗

PubMed2026

Experiences and perceptions of lay bystanders responding to out-of-hospital cardiac arrest: A qualitative systematic review.

BACKGROUND: To synthesize the experiences and perceptions of lay bystanders before, during, and after responding to out-of-hospital cardiac arrests. METHODS: Seven English and Chinese databases were searched from their inception to July 31, 2026, supplemented with citation tracking. Two reviewers independently selected studies, appraised methodological quality using the Joanna Briggs Institute (JBI) critical appraisal checklist for qualitative research, and extracted the findings and supporting illustrations. Unequivocal and credible findings were synthesized using JBI meta-aggregation, and confidence was assessed using confidence in the evidence from reviews of qualitative research. RESULTS: Eight studies involving 209 participants were included. Thirty-three findings were grouped into 12 categories and 4 were synthesized findings concerning the motivators and inhibitors of response, recognition and appraisal of out-of-hospital cardiac arrest, conditions facilitating or impeding cardiopulmonary resuscitation and automated external defibrillator use, and post-event psychological responses and adjustment. Confidence in the evidence from reviews of qualitative research was moderate for the 1st 3 synthesized findings, and low for the 4th. CONCLUSION: Bystander response is a continuum that extends from event recognition and action to post-event adjustment. Out-of-hospital cardiac arrest systems should provide realistic preparations, clear on-scene support, proportionate information, and psychological support after an event.

Humans↗

PubMed2026

Prevalence of Breastfeeding in Infants With Down Syndrome: A Systematic Review and Meta-Analysis.

AIM: To estimate the prevalence of breastfeeding-overall, exclusive, partial and depending on infants' age-in infants with Down syndrome, and to investigate associated factors. METHODS: A systematic literature search was conducted in Medline, Cochrane Library, Web of Science, Embase, CINAHL and SciELO up to 1 August 2024. Original articles that estimated the prevalence of breastfeeding in infants with Down syndrome, written in French, English or Spanish, were included. Study quality was assessed using the Joanna Briggs Institute (JBI) scale. Meta-analyses were performed for breastfeeding outcomes and meta-regression explored heterogeneity. The review was registered in PROSPERO (CRD42021278019). RESULTS: Twenty-six studies (3463 infants) were included. The estimated prevalence of overall breastfeeding regardless of duration was 71.6% (95% CI [60.3; 80.7]; 25 studies, 3351 infants) with high heterogeneity, I2 = 94%. The estimated prevalence of exclusive breastfeeding was 38.4% (95% CI [22.4; 57.3]; 10 studies, 1099 infants). No factor assessed in meta-regression was significantly associated with overall breastfeeding. CONCLUSION: The estimated breastfeeding prevalence in infants with Down syndrome is similar to that reported in the general population, despite high heterogeneity. Further studies using standardised methodology to assess breastfeeding barriers and facilitators in the context of Down syndrome would allow us to improve support for breastfeeding.

Humans↗

PubMed2026

Evaluation of oral health-related quality of life following pulp therapy or extraction in paediatric patients: a systematic review.

BACKGROUND: Treatment decision between pulp therapy and extraction for compromised teeth in paediatric patients remains a topic of debate. While both approaches address the associated pain, their long-term impact on children's well-being remains unclear. This systematic review aimed to analyse and compare the impact of pulp therapy and extraction on OHRQoL in paediatric patients. METHODS: This review was conducted in accordance with PRISMA guidelines. A comprehensive search was performed in multiple electronic databases. Methodological quality and risk of bias were evaluated using the RoB 2 tool for randomised controlled trials, ROBINS-I tool for non-randomised trials, and the Newcastle-Ottawa Scale for observational studies. RESULTS: Seven studies comprising a total of 1367 participants met the inclusion criteria. The results indicated that pulp therapy was associated with superior OHRQoL outcomes compared to extraction. Children who underwent pulp therapy reported lower anxiety, better emotional well-being, and higher parental satisfaction. Given the heterogeneity among the studies, a narrative synthesis was performed. CONCLUSION: Pulp therapy may offer better OHRQoL outcomes than extractions in paediatric patients by preserving function, reducing anxiety, and minimising long-term complications. However, these findings should be interpreted cautiously since the available evidence was limited and of low to very low certainty. Further well-designed randomised controlled trials are required.

Children↗

PubMed2026

Vitamin B12 Deficiency in Sickle Cell Disease: Method-Driven Estimates and Systematic Diagnostic Misclassification.

OBJECTIVES: To determine whether the reported 0%-70% prevalence of vitamin B12 deficiency in sickle cell disease (SCD) reflects true population variation or diagnostic misclassification. METHODS: We conducted a PRISMA 2020-compliant systematic review of observational studies (January 1, 2000-May 13, 2026; PROSPERO CRD420251087800) assessing B12 status in SCD. PubMed, AJOL, and Google Scholar were searched with citation tracking and dual screening. Diagnostic validity was assessed across biomarker strategy, analytical platform, thresholds, and confounder control using a proposed context-integrated framework to classify methodological robustness and discordance. RESULTS: Fourteen studies were included (57% high-income; 43% LMIC). The evidence base was dominated by limited diagnostic approaches: 71% used immunoassays, over one-third relied on circulating B12 alone, and functional biomarkers were inconsistently applied without systematic confounder adjustment. Prevalence estimates were strongly influenced by diagnostic methods rather than underlying population biology, ranging from 0% to 70% in single-marker studies (mostly 0%-7.1%, with outliers ~50%-70%) and 6.9%-53% in multi-marker studies. Discordance was substantial and greater in LMIC settings than HIC. CONCLUSION: Current diagnostic approaches in SCD appear method-dependent, generating heterogeneous prevalence estimates with uncertain clinical validity. These findings challenge existing estimates and have implications for clinical practice, research design, and diagnostic equity. TRIAL REGISTRATION: ClinicalTrials.gov identifier: CRD420251087800.

Humans↗