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2,320 result(s) for "Cluster randomised"
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Must Epidemiologically Impactful Vector Control Interventions Disrupt Mosquito Population Structure? A Case Study of a Cluster‐Randomised Controlled Trial
Large epidemiological impacts resulting from disease vector control interventions are typically associated with significant disruption of vector populations. While vector density is a frequently measured response, impacts on demography and connectivity are suspected but rarely quantified. We analysed low‐coverage whole‐genome sequence data of 893 Anopheles gambiae mosquitoes collected between 2014 and 2015 during a cluster‐randomized control trial (cRCT) in Burkina Faso to compare a pyrethroid‐only net (ITN) with a pyrethroid‐pyriproxyfen (ITN‐PPF) net. Despite reductions of clinical malaria by 12% and vector density by 22% in the ITN‐PPF arm, we found no significant changes in An. gambiae population genetic structure or diversity. We found remarkably low population differentiation and a lack of discernible clustering by treatment, time, or space. Nucleotide diversity and inbreeding coefficient remained stable between treatments, and genome‐wide scans showed no putative signatures of selection between trial arms. These results show that ITN‐PPF did not alter An. gambiae genetic structure, possibly due to large, vagile populations in West Africa. More widely, this is the first evidence that epidemiologically meaningful reductions in vector density may not impact genetic diversity or connectivity and challenges what constitutes adequate vector control in large populations.
The impact of adding cost information to a conversation aid to support shared decision making about low‐risk prostate cancer treatment: Results of a stepped‐wedge cluster randomised trial
Decision aids help patients consider the benefits and drawbacks of care options but rarely include cost information. We assessed the impact of a conversation-based decision aid containing information about low-risk prostate cancer management options and their relative costs. We conducted a stepped-wedge cluster randomised trial in outpatient urology practices within a US-based academic medical center. We randomised five clinicians to four intervention sequences and enroled patients newly diagnosed with low-risk prostate cancer. Primary patient-reported outcomes collected postvisit included the frequency of cost conversations and referrals to address costs. Other patient-reported outcomes included: decisional conflict postvisit and at 3 months, decision regret at 3 months, shared decision-making postvisit, financial toxicity postvisit and at 3 months. Clinicians reported their attitudes about shared decision-making pre- and poststudy, and the intervention's feasibility and acceptability. We used hierarchical regression analysis to assess patient outcomes. The clinician was included as a random effect; fixed effects included education, employment, telehealth versus in-person visit, visit date, and enrolment period. Between April 2020 and March 2022, we screened 513 patients, contacted 217 eligible patients, and enroled 117/217 (54%) (51 in usual care, 66 in the intervention group). In adjusted analyses, the intervention was not associated with cost conversations (β = .82, p = .27), referrals to cost-related resources (β = -0.36, p = .81), shared decision-making (β = -0.79, p = .32), decisional conflict postvisit (β = -0.34, p= .70), or at follow-up (β = -2.19, p = .16), decision regret at follow-up (β = -9.76, p = .11), or financial toxicity postvisit (β = -1.32, p = .63) or at follow-up (β = -2.41, p = .23). Most clinicians and patients had positive attitudes about the intervention and shared decision-making. In exploratory unadjusted analyses, patients in the intervention group experienced more transient indecision (p < .02) suggesting increased deliberation between visit and follow-up. Despite enthusiasm from clinicians, the intervention was not significantly associated with hypothesised outcomes, though we were unable to robustly test outcomes due to recruitment challenges. Recruitment at the start of the COVID-19 pandemic impacted eligibility, sample size/power, study procedures, and increased telehealth visits and financial worry, independent of the intervention. Future work should explore ways to support shared decision-making, cost conversations, and choice deliberation with a larger sample. Such work could involve additional members of the care team, and consider the detail, quality, and timing of addressing these issues. Patients and clinicians were engaged as stakeholder advisors meeting monthly throughout the duration of the project to advise on the study design, measures selected, data interpretation, and dissemination of study findings.
The Un Oeuf study: Design, methods and baseline data from a cluster randomised controlled trial to increase child egg consumption in Burkina Faso
In many low‐income countries, such as Burkina Faso, rates of malnutrition are high among children. Research indicates that animal source foods may provide important elements to improve growth and development of young children, especially during periods of rapid development, such as the first 1,000 days of life. The Un Oeuf study is designed to test an innovative behaviour change communication strategy to increase egg consumption in children 6–24 months in Burkina Faso, thereby improving dietary diversity and nutritional outcomes. This 1‐year cluster randomised controlled trial tests whether the gifting of chickens by a community champion directly to a child, combined with a behaviour change package of integrated poultry management and human nutrition trainings, can significantly increase egg consumption among children under 2 years in rural communities where egg consumption is very low. The nutrition‐sensitive behaviour change package is designed to increase egg consumption through improving livestock production, women's empowerment and food security at the household level. This paper presents a detailed account of the study design and protocol for the Un Oeuf study, alongside a description of the study population. Baseline data show a study population with high rates of malnutrition (stunting 21.6%, wasting 10.8% and underweight 20.4%) and a very low rate of egg consumption—less than 10% among children. Although poultry production is quite common, egg consumption is low reportedly because of cultural norms, including widespread practice of allowing eggs to hatch and a lack of knowledge about the nutritional benefits of egg consumption.
The global forum on bioethics in research meeting, “ethics of alternative clinical trial designs and methods in low- and middle-income country research”: emerging themes and outputs
Alternative clinical trial designs and methods are increasingly being used in place of the conventional individually randomised controlled trial (RCT) in high-income and in low-income and middle-income country (LMIC) research. These approaches - including adaptive, cluster-randomised and stepped-wedge designs and controlled human infection models - offer a number of potential advantages, including being more efficient and making the clinical trial process more socially acceptable. However, these designs and methods are generally not familiar to researchers, research ethics committees and regulators and their ethical implications have not received sufficient international attention from the bioethics, research, and policymaking communities working together. The ethics of alternative clinical trial designs and methods in LMIC research was chosen as a topic for the 2017 Global Forum on Bioethics in Research (GFBR). The meeting opened a global dialogue about this emerging issue in research ethics and gave voice to the LMIC perspective. It identified the need to take a multidisciplinary approach and to develop capacity amongst researchers and research ethics committees and regulators to propose, review and regulate these novel designs and methods. Building skills and infrastructure will empower researchers to choose from a broad range of designs and methods and adopt the most scientifically suitable, efficient, ethical and context-appropriate of these. The need for capacity development is most pressing from the LMIC perspective, where limited resources create an urgency to seek the most efficient trial design and method. The aim of this paper is to encourage broad debate about this complex area of research. By opening up this debate, GFBR aims to promote the appropriate and ethical use of novel designs and methods so their full potential to address the health needs in LMICs can be realised.
Effectiveness and cost-effectiveness of four different strategies for SARS-CoV-2 surveillance in the general population (CoV-Surv Study): study protocol for a two-factorial randomized controlled multi-arm trial with cluster sampling
Background To achieve higher effectiveness in population-based SARS-CoV-2 surveillance and to reliably predict the course of an outbreak, screening, and monitoring of infected individuals without major symptoms (about 40% of the population) will be necessary. While current testing capacities are also used to identify such asymptomatic cases, this rather passive approach is not suitable in generating reliable population-based estimates of the prevalence of asymptomatic carriers to allow any dependable predictions on the course of the pandemic. Methods This trial implements a two-factorial, randomized, controlled, multi-arm, prospective, interventional, single-blinded design with cluster sampling and four study arms, each representing a different SARS-CoV-2 testing and surveillance strategy based on individuals’ self-collection of saliva samples which are then sent to and analyzed by a laboratory. The targeted sample size for the trial is 10,000 saliva samples equally allocated to the four study arms (2500 participants per arm). Strategies differ with respect to tested population groups (individuals vs. all household members) and testing approach (without vs. with pre-screening survey). The trial is complemented by an economic evaluation and qualitative assessment of user experiences. Primary outcomes include costs per completely screened person, costs per positive case, positive detection rate, and precision of positive detection rate. Discussion Systems for active surveillance of the general population will gain more importance in the context of pandemics and related disease prevention efforts. The pandemic parameters derived from such active surveillance with routine population monitoring therefore not only enable a prospective assessment of the short-term course of a pandemic, but also a more targeted and thus more effective use of local and short-term countermeasures. Trial registration ClinicalTrials.gov DRKS00023271 . Registered November 30, 2020, with the German Clinical Trials Register (Deutsches Register Klinischer Studien)
Implementation of the patient version of the evidence-based (S3) guideline for psychosocial interventions for patients with severe mental illness (IMPPETUS): study protocol for a cluster randomised controlled trial
Background The German guideline on psychosocial interventions for people with severe mental disorders recommends a broad spectrum of evidence-based treatments. Structured implementation of the associated patient version of the guideline is missing to date. The study aims to assess whether structured implementation of a patient guideline improves the empowerment of patients with severe mental disorders, as well as knowledge, attitudes and experiences regarding psychosocial interventions, service use, treatment satisfaction, treatment needs, quality of life and burden of care. Methods The study is a multicentre, cluster-randomised, controlled study with two parallel groups. Inpatients and day hospital patients (all sexes; 18–65 years) with severe mental disorders will be included. Additionally, relatives of patients with mental disorders (all sexes; ≥ 18 years) will be included. In the experimental group, the patient guideline will be implemented using a multimodal strategy. Participants in the control group will receive treatment as usual but will be made aware of the patient guideline. The primary outcome is the change of empowerment, assessed by using the ‘empowerment in the process of psychiatric treatment of patients with affective and schizophrenia disorders’ (EPAS) scale. In addition, knowledge, attitudes and experiences regarding psychosocial interventions will be assessed as secondary outcomes, as well as service use, satisfaction with care, patient need and quality of life and participation and social inclusion. For relatives, the perceived burden of care also will be recorded. Results will be analysed using hierarchical linear models. For the health economic evaluation, the incremental cost-utility ratios will be computed using the differences in total costs of illness and the differences in quality-adjusted life years (QALY) between study groups. Discussion The study will be the first to assess the effects of a structured implementation of the patient version of a psychiatric treatment guideline. The study has some limitations regarding the transferability of the results to other patients and other regions. Furthermore, problems with the recruitment of patients and relatives and with the implementation of intervention could occur during the study. Trial registration The study is registered in the German Clinical Trials Register (DRKS) and the WHO International Clinical Trials Registry Platform (ICTRP) under registration number DRKS00017577 (Date of registration: 23 October 2019.
Community‐based differentiated service delivery models incorporating multi‐month dispensing of antiretroviral treatment for newly stable people living with HIV receiving single annual clinical visits: a pooled analysis of two cluster‐randomized trials in southern Africa
Introduction Differentiated service delivery (DSD) models for HIV treatment decrease health facility visit frequency and limit healthcare facility‐based exposure to severe acute respiratory syndrome coronavirus 2. However, two important evidence gaps include understanding DSD effectiveness amongst clients commencing DSD within 12 months of antiretroviral treatment (ART) initiation and amongst clients receiving only single annual clinical consultations. To investigate these, we pooled data from two cluster‐randomized trials investigating community‐based DSD in Zimbabwe and Lesotho. Methods Individual‐level participant data of newly stable adults enrolled between 6 and 12 months after ART initiation were pooled. Both trials (conducted between August 2017 and July 2019) had three arms: Standard‐of‐care three‐monthly ART provision at healthcare facilities (SoC, control); ART provided three‐monthly in community ART groups (CAGs) (3MC) and ART provided six‐monthly in either CAGs or at community‐distribution points (6MC). Clinical visits were three‐monthly in SoC and annually in intervention arms. The primary outcome was retention in care and secondary outcomes were viral suppression (VS) and number of unscheduled facility visits 12 months after enrolment. Individual‐level regression analyses were conducted by intention‐to‐treat specifying for clustering and adjusted for country. Results and Discussion A total of 599 participants were included; 212 (35.4%), 128 (21.4%) and 259 (43.2%) in SoC, 3MC and 6MC, respectively. Few participants aged <25 years were included (n = 32). After 12 months, 198 (93.4%), 123 (96.1%) and 248 (95.8%) were retained in SoC, 3MC and 6MC, respectively. Retention in 3MC was superior versus SoC, adjusted risk difference (aRD) = 4.6% (95% CI: 0.7%−8.5%). Retention in 6MC was non‐inferior versus SoC, aRD = 1.7% (95% CI: −2.5%−5.9%) (prespecified non‐inferiority aRD margin −3.25%). VS was similar between arms, 99.3, 98.6 and 98.1% in SoC, 3MC and 6MC, respectively. Adjusted risk ratio's for VS were 0.98 (95% CI: 0.92−1.03) for 3MC versus SoC, and 0.98 (CI: 0.95−1.00) for 6MC versus SoC. Unscheduled clinic visits were not increased in intervention arms: incidence rate ratio = 0.53 (CI: 0.16−1.80) for 3MC versus SoC; and 0.82 (CI: 0.25−2.79) for 6MC versus SoC. Conclusions Community‐based DSD incorporating three‐ and six‐monthly ART refills and single annual clinical visits were at least non‐inferior to standard facility‐based care amongst newly stable ART clients aged ≥25 years. ClinicalTrials.gov: NCT03238846 & NCT03438370
An educational intervention to prevent overweight in pre-school years: a cluster randomised trial with a focus on disadvantaged families
Background Early prevention is a promising strategy for reducing obesity in childhood, and Early Years settings are ideal venues for interventions. This work evaluated an educational intervention with the primary aim of preventing overweight and obesity in pre-school children. Methods A pragmatic, cluster randomised trial with a parallel, matched-pair design was undertaken. Interventions were targeted at both the cluster (Early Years’ Centres, matched by geographical area) and individual participant level (families: mother and 2-year old child). At the cluster level, a staff training intervention used the educational resource Be Active, Eat Healthy. Policies and provision for healthy eating and physical activity were evaluated at baseline and 12-months. The intervention at participant level was the Healthy Heroes Activity Pack : delivered over 6 months by Centre staff to promote healthy eating and physical activity in a fun, interactive way. Child and parent height and weight were measured at four time-points over 2 years. The trial primary outcome was the change in BMI z-score of the child between ages 2 and 4 years. Secondary outcomes consisted of parent-reported measures administered at baseline and two-year follow-up. Results Five pairs of Early Years’ Centres were recruited. Four pairs were analysed as one Centre withdrew (47 intervention families; 34 control families). At the cluster level, improvement in Centre policies and practices was similar for both groups ( p  = 0.830). At the participant level, the intervention group reduced their mean BMI z-score between age 2 and 4 years ( p  = 0.002; change difference 0.49; 95% CI 0.17 to 0.80) whereas the control group showed increasing BMI z-score throughout. Changes in parent-reported outcomes and parent BMI ( p  = 0.582) were similar in both groups. Conclusions The Healthy Heroes educational resource deterred excess weight gain in pre-school children from poor socioeconomic areas. With training, Early Years’ staff can implement the Healthy Heroes programme. Trial registration ISRCTN22620137 Registered 21st December 2016.
Fixed‐dose combination therapy‐based protocol compared with free pill combination protocol: Results of a cluster randomized trial
Fixed‐dose combination (FDC) therapy is recommended for hypertension management in Nigeria based on randomized trials at the individual level. This cluster‐randomized trial evaluates effectiveness and safety of a treatment protocol that used two‐drug FDC therapy as the second and third steps for hypertension control compared with a protocol that used free pill combinations. From January 2021 to June 2021, 60 primary healthcare centers in the Federal Capital Territory of Nigeria were randomized to a protocol using FDC therapy as second and third steps compared with a protocol that used the same medications in free pill combination therapy for these steps. Eligible patients were adults (≥18 years) with hypertension. The primary outcome was the odds of a patient being controlled at their last visit between baseline to 6‐month follow‐up in the FDC group compared to the free pill group. 4427 patients (mean [SD] age: 49.0 [12.4] years, 70.5% female) were registered with mean (SD) baseline systolic/diastolic blood pressure 155 (20.6)/96 (13.1) mm Hg. Baseline characteristics of groups were similar. After 6‐months, hypertension control rate improved in the two treatment protocols, but there were no differences between the groups after adjustment (FDC = 53.9% versus free pill combination = 47.9%, cluster‐adjusted p = .29). Adverse events were similarly low (<1%) in both groups. Both protocols improved hypertension control rates at 6‐months in comparison to baseline, though no differences were observed between groups. Further work is needed to determine if upfront FDC therapy is more effective and efficient to improve hypertension control rates.
Accounting for interactions and complex inter-subject dependency in estimating treatment effect in cluster-randomized trials with missing outcomes
Semi-parametric methods are often used for the estimation of intervention effects on correlated outcomes in cluster-randomized trials (CRTs). When outcomes are missing at random (MAR), Inverse Probability Weighted (IPW) methods incorporating baseline covariates can be used to deal with informative missingness. Also, augmented generalized estimating equations (AUG) correct for imbalance in baseline covariates but need to be extended for MAR outcomes. However, in the presence of interactions between treatment and baseline covariates, neither method alone produces consistent estimates for the marginal treatment effect if the model for interaction is not correctly specified. We propose an AUG–IPW estimator that weights by the inverse of the probability of being a complete case and allows different outcome models in each intervention arm. This estimator is doubly robust (DR); it gives correct estimates whether the missing data process or the outcome model is correctly specified. We consider the problem of covariate interference which arises when the outcome of an individual may depend on covariates of other individuals. When interfering covariates are not modeled, the DR property prevents bias as long as covariate interference is not present simultaneously for the outcome and the missingness. An R package is developed implementing the proposed method. An extensive simulation study and an application to a CRT of HIV risk reduction-intervention in South Africa illustrate the method.