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1.
PLoS One ; 19(5): e0304892, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38820311

RESUMEN

[This corrects the article DOI: 10.1371/journal.pone.0286218.].

2.
Ann Appl Stat ; 18(1): 350-374, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38455841

RESUMEN

Assessing heterogeneity in the effects of treatments has become increasingly popular in the field of causal inference and carries important implications for clinical decision-making. While extensive literature exists for studying treatment effect heterogeneity when outcomes are fully observed, there has been limited development in tools for estimating heterogeneous causal effects when patient-centered outcomes are truncated by a terminal event, such as death. Due to mortality occurring during study follow-up, the outcomes of interest are unobservable, undefined, or not fully observed for many participants in which case principal stratification is an appealing framework to draw valid causal conclusions. Motivated by the Acute Respiratory Distress Syndrome Network (ARDSNetwork) ARDS respiratory management (ARMA) trial, we developed a flexible Bayesian machine learning approach to estimate the average causal effect and heterogeneous causal effects among the always-survivors stratum when clinical outcomes are subject to truncation. We adopted Bayesian additive regression trees (BART) to flexibly specify separate mean models for the potential outcomes and latent stratum membership. In the analysis of the ARMA trial, we found that the low tidal volume treatment had an overall benefit for participants sustaining acute lung injuries on the outcome of time to returning home but substantial heterogeneity in treatment effects among the always-survivors, driven most strongly by biologic sex and the alveolar-arterial oxygen gradient at baseline (a physiologic measure of lung function and degree of hypoxemia). These findings illustrate how the proposed methodology could guide the prognostic enrichment of future trials in the field.

3.
AIDS Care ; 36(6): 807-815, 2024 06.
Artículo en Inglés | MEDLINE | ID: mdl-38460152

RESUMEN

Timely HIV diagnosis and medical engagement are crucial for effective viral load suppression and treatment as prevention. However, significant delays persist, particularly in Africa, including Ghana. This study focused on Ghanaian men whose route of exposure to HIV was through same-gender sexual contact (MSM), a group disproportionately impacted by HIV. Using structured surveys, we investigated the sociodemographic factors associated with late HIV diagnosis, a topic with limited existing research. Results indicate that older age groups were associated with an increased risk of late diagnosis compared to the 18-24 age group. Among the demographic variables studied, only age showed a consistent association with late HIV diagnosis. This study underscores the importance of targeted interventions to address HIV diagnosis disparities among MSM in Ghana, particularly for older age groups. The findings emphasize the need for tailored interventions addressing age-related disparities in timely diagnosis and engagement with medical services among this population. Such interventions can play a crucial role in reducing the burden of HIV within this community and fostering improved public health outcomes.


Asunto(s)
Diagnóstico Tardío , Infecciones por VIH , Homosexualidad Masculina , Humanos , Masculino , Ghana/epidemiología , Infecciones por VIH/diagnóstico , Infecciones por VIH/epidemiología , Adulto , Homosexualidad Masculina/estadística & datos numéricos , Adulto Joven , Diagnóstico Tardío/estadística & datos numéricos , Adolescente , Persona de Mediana Edad , Factores de Riesgo , Factores de Edad , Factores Sociodemográficos , Factores Socioeconómicos , Estudios Transversales , Encuestas y Cuestionarios , Conducta Sexual
4.
JAMA Surg ; 159(4): 461-463, 2024 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-38324281

RESUMEN

This cross-sectional study examines federal funding, registered clinical trials, and publications to quantify trends in firearm injury prevention research in the US from 1985 to 2022.


Asunto(s)
Armas de Fuego , Heridas por Arma de Fuego , Humanos , Investigación sobre Servicios de Salud , Estados Unidos , Heridas por Arma de Fuego/epidemiología , Heridas por Arma de Fuego/prevención & control , Ensayos Clínicos como Asunto
5.
Clin Trials ; : 17407745231222018, 2024 Jan 10.
Artículo en Inglés | MEDLINE | ID: mdl-38197388

RESUMEN

BACKGROUND: Heterogeneous outcome correlations across treatment arms and clusters have been increasingly acknowledged in cluster randomized trials with binary endpoints, where analytical methods have been developed to study such heterogeneity. However, cluster-specific outcome variances and correlations have yet to be studied for cluster randomized trials with continuous outcomes. METHODS: This article proposes models fitted in the Bayesian setting with hierarchical variance structure to quantify heterogeneous variances across clusters and explain it with cluster-level covariates when the outcome is continuous. The models can also be extended to analyzing heterogeneous variances in individually randomized group treatment trials, with arm-specific cluster-level covariates, or in partially nested designs. Simulation studies are carried out to validate the performance of the newly introduced models across different settings. RESULTS: Simulations showed that overall the newly introduced models have good performance, reporting low bias and approximately 95% coverage for the intraclass correlation coefficients and regression parameters in the variance model. When variances are heterogeneous, our proposed models had improved model fit over models with homogeneous variances. When used to analyze data from the Kerala Diabetes Prevention Program study, our models identified heterogeneous variances and intraclass correlation coefficients across clusters and examined cluster-level characteristics associated with such heterogeneity. CONCLUSION: We proposed new hierarchical Bayesian variance models to accommodate cluster-specific variances in cluster randomized trials. The newly developed methods inform the understanding of how an intervention strategy is implemented and disseminated differently across clusters and can help improve future trial design.

6.
J Am Acad Child Adolesc Psychiatry ; 63(3): 336-344, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-37619938

RESUMEN

OBJECTIVE: A natural experiment that provided income supplements to families has been associated with beneficial outcomes for children that persisted into adulthood. The children in this study are now adults, and many are parents. METHOD: The study builds on the longitudinal, representative Great Smoky Mountains study conducted from 1993 to 2020. At follow-up in their late 30s, 1,094 of the 1,348 living participants (81.2%) were assessed. Of these participants (67.6%), 739 were parents. A tribe in the area implemented a cash transfer program of approximately $5,000 annually per person to every tribal member based on the profits received from operating a casino. Ten aspects of the home environment of participants were assessed (eg, family chaos, substance use, and food insecurity) as well as a composite measure across all home environment indicators. The proposed analyses were preregistered (https://osf.io/ex638). RESULTS: Of the 739 parents assessed, 192 (26.0%) were American Indians. Parents whose families received cash transfers during childhood did not differ from parents whose families did not receive cash transfers on any of the home environment indicators or the composite measure. At the same time, there was little evidence of elevated risk for participants in either group in measures of parental mental health, substance use, and violence. CONCLUSION: A family cash transfer in childhood that had long-term effects on individual functioning did not impact the home environment of participants who became parents. Rather, parents in both groups were providing home environments generally conducive to their children's growth and development. STUDY PREREGISTRATION INFORMATION: Intergenerational Effects of a Family Cash Transfer on the Home Environment; https://osf.io/; ex638.


Asunto(s)
Ambiente en el Hogar , Trastornos Relacionados con Sustancias , Niño , Adulto , Humanos , Renta , Padres
7.
Stat Med ; 43(1): 16-33, 2024 01 15.
Artículo en Inglés | MEDLINE | ID: mdl-37985966

RESUMEN

In many medical studies, the outcome measure (such as quality of life, QOL) for some study participants becomes informatively truncated (censored, missing, or unobserved) due to death or other forms of dropout, creating a nonignorable missing data problem. In such cases, the use of a composite outcome or imputation methods that fill in unmeasurable QOL values for those who died rely on strong and untestable assumptions and may be conceptually unappealing to certain stakeholders when estimating a treatment effect. The survivor average causal effect (SACE) is an alternative causal estimand that surmounts some of these issues. While principal stratification has been applied to estimate the SACE in individually randomized trials, methods for estimating the SACE in cluster-randomized trials are currently limited. To address this gap, we develop a mixed model approach along with an expectation-maximization algorithm to estimate the SACE in cluster-randomized trials. We model the continuous outcome measure with a random intercept to account for intracluster correlations due to cluster-level randomization, and model the principal strata membership both with and without a random intercept. In simulations, we compare the performance of our approaches with an existing fixed-effects approach to illustrate the importance of accounting for clustering in cluster-randomized trials. The methodology is then illustrated using a cluster-randomized trial of telecare and assistive technology on health-related QOL in the elderly.


Asunto(s)
Modelos Estadísticos , Calidad de Vida , Humanos , Anciano , Ensayos Clínicos Controlados Aleatorios como Asunto , Evaluación de Resultado en la Atención de Salud , Sobrevivientes
8.
Biom J ; 66(1): e2200307, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37768850

RESUMEN

In an individually randomized group treatment (IRGT) trial, participant outcomes can be positively correlated due to, for example, shared therapists in treatment delivery. Oftentimes, because of limited treatment resources or participants at one location, an IRGT trial can be carried out across multiple centers. This design can be subject to potential correlations in the participant outcomes between arms within the same center. While the design of a single-center IRGT trial has been studied, little is known about the planning of a multicenter IRGT trial. To address this gap, this paper provides analytical sample size formulas for designing multicenter IRGT trials with a continuous endpoint under the linear mixed model framework. We found that accounting for the additional center-level correlation at the design stage can lead to sample size reduction, and the magnitude of reduction depends on the amount of between-therapist correlation. However, if the variance components of therapist-level random effects are considered as input parameters in the design stage, accounting for the additional center-level variance component has no impact on the sample size estimation. We presented our findings through numeric illustrations and performed simulation studies to validate our sample size procedures under different scenarios. Optimal design configurations under the multicenter IRGT trials have also been discussed, and two real-world trial examples are drawn to illustrate the use of our method.


Asunto(s)
Proyectos de Investigación , Humanos , Análisis por Conglomerados , Simulación por Computador , Modelos Lineales , Tamaño de la Muestra
9.
Clin Trials ; 21(2): 199-210, 2024 04.
Artículo en Inglés | MEDLINE | ID: mdl-37990575

RESUMEN

BACKGROUND/AIMS: The stepped-wedge cluster randomized trial (SW-CRT), in which clusters are randomized to a time at which they will transition to the intervention condition - rather than a trial arm - is a relatively new design. SW-CRTs have additional design and analytical considerations compared to conventional parallel arm trials. To inform future methodological development, including guidance for trialists and the selection of parameters for statistical simulation studies, we conducted a review of recently published SW-CRTs. Specific objectives were to describe (1) the types of designs used in practice, (2) adherence to key requirements for statistical analysis, and (3) practices around covariate adjustment. We also examined changes in adherence over time and by journal impact factor. METHODS: We used electronic searches to identify primary reports of SW-CRTs published 2016-2022. Two reviewers extracted information from each trial report and its protocol, if available, and resolved disagreements through discussion. RESULTS: We identified 160 eligible trials, randomizing a median (Q1-Q3) of 11 (8-18) clusters to 5 (4-7) sequences. The majority (122, 76%) were cross-sectional (almost all with continuous recruitment), 23 (14%) were closed cohorts and 15 (9%) open cohorts. Many trials had complex design features such as multiple or multivariate primary outcomes (50, 31%) or time-dependent repeated measures (27, 22%). The most common type of primary outcome was binary (51%); continuous outcomes were less common (26%). The most frequently used method of analysis was a generalized linear mixed model (112, 70%); generalized estimating equations were used less frequently (12, 8%). Among 142 trials with fewer than 40 clusters, only 9 (6%) reported using methods appropriate for a small number of clusters. Statistical analyses clearly adjusted for time effects in 119 (74%), for within-cluster correlations in 132 (83%), and for distinct between-period correlations in 13 (8%). Covariates were included in the primary analysis of the primary outcome in 82 (51%) and were most often individual-level covariates; however, clear and complete pre-specification of covariates was uncommon. Adherence to some key methodological requirements (adjusting for time effects, accounting for within-period correlation) was higher among trials published in higher versus lower impact factor journals. Substantial improvements over time were not observed although a slight improvement was observed in the proportion accounting for a distinct between-period correlation. CONCLUSIONS: Future methods development should prioritize methods for SW-CRTs with binary or time-to-event outcomes, small numbers of clusters, continuous recruitment designs, multivariate outcomes, or time-dependent repeated measures. Trialists, journal editors, and peer reviewers should be aware that SW-CRTs have additional methodological requirements over parallel arm designs including the need to account for period effects as well as complex intracluster correlations.


Asunto(s)
Proyectos de Investigación , Humanos , Análisis por Conglomerados , Ensayos Clínicos Controlados Aleatorios como Asunto , Simulación por Computador , Modelos Lineales , Tamaño de la Muestra
10.
JAMA Netw Open ; 6(10): e2336907, 2023 10 02.
Artículo en Inglés | MEDLINE | ID: mdl-37851447

RESUMEN

Importance: Young adults in their 20s are at high relative risk for self- and other-directed firearm injury, but little is known about gun access patterns for this group. Objective: To describe the longitudinal patterns of firearm access from childhood to young adulthood and to estimate whether violence experienced as a child or as an adult is associated with gun ownership in young adulthood. Design, Setting, and Participants: The Great Smoky Mountains Study included participants from 11 contiguous, mostly rural counties in the Southeastern US. The first wave was completed in 1993 and the most recent in 2019. Periodic survey data were gathered in adolescence through participants' late 20s. In 2023, adjusted Poisson regression with incident rate ratios (IRRs) and 95% CIs were used to estimate associations between violence and gun ownership in young adulthood in 3 age cohorts from the original sample. Exposures: Violent experiences in childhood (bullying, sexual and physical abuse, violent events, witnessing trauma, physical violence between parents, and school/neighborhood dangerousness) or adulthood (physical and sexual assault). Main Outcomes and Measures: Initiating gun ownership was defined as no gun access or ownership in childhood followed by gun ownership at age 25 or 30 years. Maintaining gun ownership was defined as reporting gun access or ownership in at least 1 survey in childhood and ownership at age 25 or 30 years. Results: Among 1260 participants (679 [54%] male; ages 9, 11, and 13 years), gun access or ownership was more common in childhood (women: 366 [63%]; men: 517 [76%]) than in adulthood (women: 207 [36%]; men: 370 [54%]). The most common longitudinal pattern was consistent access or ownership from childhood to adulthood (373 [35%]) followed by having access or ownership in childhood only (408 [32%]). Most of the violent exposures evaluated were not significantly associated with the outcomes. Being bullied at school was common and was associated with reduced ownership initiation (IRR, 0.76; 95% CI, 0.61-0.94). Witnessing a violent event was significantly associated with increased probability of becoming a gun owner in adulthood (IRR, 1.24; 95% CI, 1.03-1.49). Conclusions and Relevance: In this cohort study, gun ownership and access were transitory, even in a geographic area where gun culture is strong. Early adulthood-when the prevalence of gun ownership was relatively low-may represent an opportune time for clinicians and communities to provide education on the risks associated with firearm access, as well as strategies for risk mitigation.


Asunto(s)
Armas de Fuego , Heridas por Arma de Fuego , Niño , Adolescente , Adulto Joven , Humanos , Masculino , Femenino , Adulto , Estudios de Cohortes , Propiedad , Heridas por Arma de Fuego/epidemiología , Violencia
11.
BMC Public Health ; 23(1): 1545, 2023 08 14.
Artículo en Inglés | MEDLINE | ID: mdl-37580653

RESUMEN

BACKGROUND: We describe the rationale and study design for "TRUsted rEsidents and Housing Assistance to decrease Violence Exposure in New Haven (TRUE HAVEN)," a prospective type 1 hybrid effectiveness/implementation study of a multi-level intervention using a stepped wedge design. TRUE HAVEN aims to lower rates of community gun violence by fostering the stability, wealth, and well-being of individuals and families directly impacted by incarceration through the provision of stable housing and by breaking the cycle of trauma. DESIGN: TRUE HAVEN is an ongoing, multi-level intervention with three primary components: financial education paired with housing support (individual level), trauma-informed counseling (neighborhood level), and policy changes to address structural racism (city/state level). Six neighborhoods with among the highest rates of gun violence in New Haven, Connecticut, will receive the individual and neighborhood level intervention components sequentially beginning at staggered 6-month steps. Residents of these neighborhoods will be eligible to participate in the housing stability and financial education component if they were recently incarcerated or are family members of currently incarcerated people; participants will receive intense financial education and follow-up for six months and be eligible for special down payment and rental assistance programs. In addition, trusted community members and organization leaders within each target neighborhood will participate in trauma-informed care training sessions to then be able to recognize when their peers are suffering from trauma symptoms, to support these affected peers, and to destigmatize accessing professional mental health services and connect them to these services when needed. Finally, a multi-stakeholder coalition will be convened to address policies that act as barriers to housing stability or accessing mental healthcare. Interventions will be delivered through existing partnerships with community-based organizations and networks. The primary outcome is neighborhood rate of incident gun violence. To inform future implementation and optimize the intervention package as the study progresses, we will use the Learn As You Go approach to optimize and assess the effectiveness of the intervention package on the primary study outcome. DISCUSSION: Results from this protocol will yield novel evidence for whether and how addressing structural racism citywide leads to a reduction in gun violence. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT05723614. Registration date: February 01, 2023. Please refer to https://clinicaltrials.gov/ct2/show/NCT05723614 for public and scientific inquiries.


Asunto(s)
Exposición a la Violencia , Violencia con Armas , Servicios de Salud Mental , Humanos , Estudios Prospectivos , Vivienda Popular
13.
Stat Med ; 42(19): 3392-3412, 2023 08 30.
Artículo en Inglés | MEDLINE | ID: mdl-37316956

RESUMEN

An important consideration in the design and analysis of randomized trials is the need to account for outcome observations being positively correlated within groups or clusters. Two notable types of designs with this consideration are individually randomized group treatment trials and cluster randomized trials. While sample size methods for testing the average treatment effect are available for both types of designs, methods for detecting treatment effect modification are relatively limited. In this article, we present new sample size formulas for testing treatment effect modification based on either a univariate or multivariate effect modifier in both individually randomized group treatment and cluster randomized trials with a continuous outcome but any types of effect modifier, while accounting for differences across study arms in the outcome variance, outcome intracluster correlation coefficient (ICC) and the cluster size. We consider cases where the effect modifier can be measured at either the individual level or cluster level, and with a univariate effect modifier, our closed-form sample size expressions provide insights into the optimal allocation of groups or clusters to maximize design efficiency. Overall, our results show that the required sample size for testing treatment effect heterogeneity with an individual-level effect modifier can be affected by unequal ICCs and variances between arms, and accounting for such between-arm heterogeneity can lead to more accurate sample size determination. We use simulations to validate our sample size formulas and illustrate their application in the context of two real trials: an individually randomized group treatment trial (the AWARE study) and a cluster randomized trial (the K-DPP study).


Asunto(s)
Proyectos de Investigación , Humanos , Tamaño de la Muestra , Análisis por Conglomerados , Ensayos Clínicos Controlados Aleatorios como Asunto
14.
Psychol Med ; 53(16): 7581-7590, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37203460

RESUMEN

BACKGROUND: It is unknown how much variation in adult mental health problems is associated with differences between societal/cultural groups, over and above differences between individuals. METHODS: To test these relative contributions, a consortium of indigenous researchers collected Adult Self-Report (ASR) ratings from 16 906 18- to 59-year-olds in 28 societies that represented seven culture clusters identified in the Global Leadership and Organizational Behavioral Effectiveness study (e.g. Confucian, Anglo). The ASR is scored on 17 problem scales, plus a personal strengths scale. Hierarchical linear modeling estimated variance accounted for by individual differences (including measurement error), society, and culture cluster. Multi-level analyses of covariance tested age and gender effects. RESULTS: Across the 17 problem scales, the variance accounted for by individual differences ranged from 80.3% for DSM-oriented anxiety problems to 95.2% for DSM-oriented avoidant personality (mean = 90.7%); by society: 3.2% for DSM-oriented somatic problems to 8.0% for DSM-oriented anxiety problems (mean = 6.3%); and by culture cluster: 0.0% for DSM-oriented avoidant personality to 11.6% for DSM-oriented anxiety problems (mean = 3.0%). For strengths, individual differences accounted for 80.8% of variance, societal differences 10.5%, and cultural differences 8.7%. Age and gender had very small effects. CONCLUSIONS: Overall, adults' self-ratings of mental health problems and strengths were associated much more with individual differences than societal/cultural differences, although this varied across scales. These findings support cross-cultural use of standardized measures to assess mental health problems, but urge caution in assessment of personal strengths.


Asunto(s)
Salud Mental , Trastornos de la Personalidad , Adulto , Humanos , Trastornos de la Personalidad/psicología , Ansiedad , Trastornos de Ansiedad , Individualidad
15.
Res Sq ; 2023 May 10.
Artículo en Inglés | MEDLINE | ID: mdl-37214890

RESUMEN

Background We describe the rationale and study design for " TRU sted r Esidents and H ousing A ssistance to decrease V iolence E xposure in N ew Haven (TRUE HAVEN)," a prospective type 1 hybrid effectiveness/implementation study of a multi-level intervention using a stepped wedge design. TRUE HAVEN aims to lower rates of community gun violence by fostering the stability, wealth, and well-being of individuals and families directly impacted by incarceration through the provision of stable housing and by breaking the cycle of trauma. Design: TRUE HAVEN is a multi-level intervention with three primary components: financial education paired with housing support (individual level), trauma-informed counseling (neighborhood level), and policy changes to address structural racism (city/state level). Six neighborhoods with among the highest rates of gun violence in New Haven, Connecticut, will receive the individual and neighborhood level intervention components sequentially beginning at staggered 6-month steps. Residents of these neighborhoods will be eligible to participate in the housing stability and financial education component if they were recently incarcerated or are family members of currently incarcerated people; participants will receive intense financial education and follow-up for six months and be eligible for special down payment and rental assistance programs. In addition, trusted community members and organization leaders within each target neighborhood will participate in trauma-informed care training sessions to then be able to recognize when their peers are suffering from trauma symptoms, to support these affected peers, and to destigmatize accessing professional mental health services and connect them to these services when needed. Finally, a multi-stakeholder coalition will be convened to address policies that act as barriers to housing stability or accessing mental healthcare. Interventions will be delivered through existing partnerships with community-based organizations and networks. The primary outcome is neighborhood rate of incident gun violence. To inform future implementation and optimize the intervention package as the study progresses, we will use the Learn As You Go approach to optimize and assess the effectiveness of the intervention package on the primary study outcome. Discussion Results from this protocol will yield novel evidence for whether and how addressing structural racism citywide leads to a reduction in gun violence. Trial registration ClinicalTrials.gov Identifier: NCT05723614. Registration date: February 01, 2023.

16.
BMC Med Res Methodol ; 23(1): 85, 2023 04 06.
Artículo en Inglés | MEDLINE | ID: mdl-37024809

RESUMEN

BACKGROUND: Detecting treatment effect heterogeneity is an important objective in cluster randomized trials and implementation research. While sample size procedures for testing the average treatment effect accounting for participant attrition assuming missing completely at random or missing at random have been previously developed, the impact of attrition on the power for detecting heterogeneous treatment effects in cluster randomized trials remains unknown. METHODS: We provide a sample size formula for testing for a heterogeneous treatment effect assuming the outcome is missing completely at random. We also propose an efficient Monte Carlo sample size procedure for assessing heterogeneous treatment effect assuming covariate-dependent outcome missingness (missing at random). We compare our sample size methods with the direct inflation method that divides the estimated sample size by the mean follow-up rate. We also evaluate our methods through simulation studies and illustrate them with a real-world example. RESULTS: Simulation results show that our proposed sample size methods under both missing completely at random and missing at random provide sufficient power for assessing heterogeneous treatment effect. The proposed sample size methods lead to more accurate sample size estimates than the direct inflation method when the missingness rate is high (e.g., ≥ 30%). Moreover, sample size estimation under both missing completely at random and missing at random is sensitive to the missingness rate, but not sensitive to the intracluster correlation coefficient among the missingness indicators. CONCLUSION: Our new sample size methods can assist in planning cluster randomized trials that plan to assess a heterogeneous treatment effect and participant attrition is expected to occur.


Asunto(s)
Modelos Estadísticos , Proyectos de Investigación , Humanos , Interpretación Estadística de Datos , Ensayos Clínicos Controlados Aleatorios como Asunto , Simulación por Computador , Tamaño de la Muestra , Análisis por Conglomerados
17.
J Clin Epidemiol ; 157: 134-145, 2023 05.
Artículo en Inglés | MEDLINE | ID: mdl-36931478

RESUMEN

OBJECTIVES: In stepped-wedge cluster randomized trials (SW-CRTs), clusters are randomized not to treatment and control arms but to sequences dictating the times of crossing from control to intervention conditions. Randomization is an essential feature of this design but application of standard methods to promote and report on balance at baseline is not straightforward. We aimed to describe current methods of randomization and reporting of balance at baseline in SW-CRTs. STUDY DESIGN AND SETTING: We used electronic searches to identify primary reports of SW-CRTs published between 2016 and 2022. RESULTS: Across 160 identified trials, the median number of clusters randomized was 11 (Q1-Q3: 8-18). Sixty-three (39%) used restricted randomization-most often stratification based on a single cluster-level covariate; 12 (19%) of these adjusted for the covariate(s) in the primary analysis. Overall, 50 (31%) and 134 (84%) reported on balance at baseline on cluster- and individual-level characteristics, respectively. Balance on individual-level characteristics was most often reported by condition in cross-sectional designs and by sequence in cohort designs. Authors reported baseline imbalances in 72 (45%) trials. CONCLUSION: SW-CRTs often randomize a small number of clusters using unrestricted allocation. Investigators need guidance on appropriate methods of randomization and assessment and reporting of balance at baseline.


Asunto(s)
Proyectos de Investigación , Humanos , Distribución Aleatoria , Estudios Transversales , Análisis por Conglomerados , Ensayos Clínicos Controlados Aleatorios como Asunto
18.
Am J Epidemiol ; 192(6): 1006-1015, 2023 06 02.
Artículo en Inglés | MEDLINE | ID: mdl-36799630

RESUMEN

Many studies encounter clustering due to multicenter enrollment and nonmortality outcomes, such as quality of life, that are truncated due to death-that is, missing not at random and nonignorable. Traditional missing-data methods and target causal estimands are suboptimal for statistical inference in the presence of these combined issues, which are especially common in multicenter studies and cluster-randomized trials (CRTs) carried out among the elderly or seriously ill. Using principal stratification, we developed a Bayesian estimator that jointly identifies the always-survivor principal stratum in a clustered/hierarchical data setting and estimates the average treatment effect among them (i.e., the survivor average causal effect (SACE)). In simulations, we observed low bias and good coverage with our method. In a motivating CRT, the SACE and the estimate from complete-case analysis differed in magnitude, but both were small, and neither was incompatible with a null effect. However, the SACE estimate has a clear causal interpretation. The option to assess the rigorously defined SACE estimand in studies with informative truncation and clustering can provide additional insight into an important subset of study participants. Based on the simulation study and CRT reanalysis, we provide practical recommendations for using the SACE in CRTs and software code to support future research.


Asunto(s)
Modelos Estadísticos , Calidad de Vida , Humanos , Anciano , Teorema de Bayes , Ensayos Clínicos Controlados Aleatorios como Asunto , Sobrevivientes
19.
Psychol Med ; 53(8): 3711-3718, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-35264271

RESUMEN

BACKGROUND: The juvenile justice system in the USA adjudicates over seven hundred thousand youth in the USA annually with significant behavioral offenses. This study aimed to test the effect of juvenile justice involvement on adult criminal outcomes. METHODS: Analyses were based on a prospective, population-based study of 1420 children followed up to eight times during childhood (ages 9-16; 6674 observations) about juvenile justice involvement in the late 1990 and early 2000s. Participants were followed up years later to assess adult criminality, using self-report and official records. A propensity score (i.e. inverse probability) weighting approach was used that approximated an experimental design by balancing potentially confounding characteristics between children with v. without juvenile justice involvement. RESULTS: Between-groups differences on variables that elicit a juvenile justice referral (e.g. violence, property offenses, status offenses, and substance misuse) were attenuated after applying propensity-based inverse probability weights. Participants with a history of juvenile justice involvement were more likely to have later official and violent felony charges, and to self-report police contact and spending time in jail (ORs from 2.5 to 3.3). Residential juvenile justice involvement was associated with the highest risk of both, later official criminal records and self-reported criminality (ORs from 5.1 to 14.5). Sensitivity analyses suggest that our findings are likely robust to potential unobserved confounders. CONCLUSIONS: Juvenile justice involvement was associated with increased risk of adult criminality, with residential services associated with highest risk. Juvenile justice involvement may catalyze rather than deter from adult offending.


Asunto(s)
Criminales , Delincuencia Juvenil , Adolescente , Niño , Humanos , Adulto , Estudios Prospectivos , Crimen , Violencia
20.
Contemp Clin Trials ; 125: 107037, 2023 02.
Artículo en Inglés | MEDLINE | ID: mdl-36460267

RESUMEN

BACKGROUND: HIV disproportionally affects persons who inject drugs (PWID), but engagement with HIV pre-exposure prophylaxis (PrEP) is low. We describe the rationale and study design for a new study, "Contingency Management and Pre-Exposure Prophylaxis (PrEP) Adherence Support Services (CoMPASS)," a hybrid type 1 effectiveness-implementation trial to promote HIV risk reduction among PWID. METHODS: In four community-based programs in the northeastern United States, PrEP-eligible PWID (target n = 526) are randomized to treatment as usual or Contingency Management (CM) and, as indicated, stepped up to PrEP Adherence Support Services (CoMPASS) over 24 weeks. During CM sessions, participants receive timely tangible rewards for verifiable activities demonstrating 1) PrEP initiation and adherence, and 2) engagement with medications for opioid use disorder (MOUD) and other OUD-related care. Participants who do not have high levels of biomarker-confirmed PrEP adherence at week 12 will be stepped up to receive PrEP Adherence Support Services (PASS) consisting of strengths-based case management over 12 weeks. Interventions are delivered by trained PrEP navigators, staff embedded within the respective sites. The primary outcome is sustained PrEP adherence by dried blood spot testing at 24 weeks. To inform future implementation, we are conducting implementation-focused process evaluations throughout the clinical trial. CONCLUSIONS: Results from this protocol are anticipated to yield novel findings regarding the impact and scalability of CoMPASS to promote HIV prevention among PWID in partnership with community-based organizations. http://ClinicalTrials.gov identifier: NCT04738825.


Asunto(s)
Fármacos Anti-VIH , Consumidores de Drogas , Infecciones por VIH , Profilaxis Pre-Exposición , Abuso de Sustancias por Vía Intravenosa , Humanos , Infecciones por VIH/prevención & control , Infecciones por VIH/tratamiento farmacológico , Fármacos Anti-VIH/uso terapéutico , Profilaxis Pre-Exposición/métodos , Abuso de Sustancias por Vía Intravenosa/complicaciones , Conducta de Reducción del Riesgo
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