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1.
Educ Res Rev ; 432024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38854741

RESUMEN

Morphemes are the smallest meaningful unit of language (e.g., affixes, base words) that express grammatical and semantic information. Additionally, morphological knowledge is significantly related to children's word reading and reading comprehension skills. Researchers have broadly assessed morphological knowledge by using a wide range of tasks and stimuli, which has influenced the interpretation of the relations between morphological knowledge and reading outcomes. This review of 103 studies used meta-analytic structural equation modeling (MASEM) to investigate the relations between commonly occurring morphological knowledge assessment features (e.g., written versus oral, spelling versus no spelling) in the literature to reading outcomes, including word reading and reading comprehension. Meta-regression techniques were used to examine moderators of age and reading ability. Morphological assessments that used a written modality (e.g., reading, writing) were more predictive of word reading outcomes than those administered orally. Assessments of morphological spelling were more predictive of both word reading and reading comprehension outcomes than those that did not examine spelling accuracy. Age was a significant moderator of the relation between morphology and word reading, such that the relation was stronger for the younger than the older children. Younger children also demonstrated higher relations between multiple task dimensions and reading comprehension, including oral tasks, tasks without decoding, and tasks that provided context clues. These findings have important implications for future morphological intervention studies aimed to improve children's reading outcomes, in particular the use of orthography and spelling within the context of teaching morphology.

2.
Campbell Syst Rev ; 20(2): e1410, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38779333

RESUMEN

This is a protocol for a systematic review and meta-analysis of research on mental health outcomes of abortion. Does abortion increase the risk of adverse mental health outcomes? That is the central question for this review. Our review aims to inform policy and practice by locating, critically appraising, and synthesizing empirical evidence on associations between abortion and subsequent mental health outcomes. Given the controversies surrounding this topic and the complex social, political, legal, and ideological contexts in which research and reviews on abortion are conducted, it is especially important to conduct this systematic review and meta-analysis with comprehensive, rigorous, unbiased, and transparent methods. We will include a variety of study designs to enhance understanding of studies' methodological strengths and weaknesses and to identify potential explanations for conflicting results. We will follow open science principles, providing access to our methods, measures, and results, and making data available for re-analysis.

3.
Campbell Syst Rev ; 19(3): e1324, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37475879

RESUMEN

Background: Functional Family Therapy (FFT) is a short-term family-based intervention for youth with behaviour problems. FFT has been widely implemented in the USA and other high-income countries. It is often described as an evidence-based program with consistent, positive effects. Objectives: We aimed to synthesise the best available data to assess the effectiveness of FFT for families of youth with behaviour problems. Search Methods: Searches were performed in 2013-2014 and August 2020. We searched 22 bibliographic databases (including PsycINFO, ERIC, MEDLINE, Science Direct, Sociological Abstracts, Social Services Abstracts, World CAT dissertations and theses, and the Web of Science Core Collection), as well as government policy databanks and professional websites. Reference lists of articles were examined, and experts were contacted to search for missing information. Selection Criteria: We included randomised controlled trials (RCTs) and quasi-experimental designs (QEDs) with parallel cohorts and statistical controls for between-group differences at baseline. Participants were families of young people aged 11-18 with behaviour problems. FFT programmes were compared with usual services, alternative treatment, and no treatment. There were no publication, geographic, or language restrictions. Data Collection and Analysis: Two reviewers independently screened 1039 titles and abstracts, read all available study reports, assessed study eligibility, and extracted data onto structured electronic forms. We assessed risks of bias (ROB) using modified versions of the Cochrane ROB tool and the What Works Clearinghouse standards. Where possible, we used random effects models with inverse variance weights to pool results across studies. We used odds ratios for dichotomous outcomes and standardised mean differences for continuous outcomes. We used Hedges g to adjust for small sample sizes. We assessed the heterogeneity of effects with χ 2 and I 2. We produced separate forest plots for conceptually distinct outcomes and for different endpoints (<9, 9-14, 15-23, and 24-42 months after referral). We grouped studies by study design (RCT or QED), and then assessed differences between these two subgroups of studies with χ 2 tests. We generated robust variance estimates, using correlated effects (CE) models with small sample corrections to synthesise all available outcome data. Exploratory CE analyses assessed potential moderators of effects within these domains. We used GRADE guidelines to assess the certainty of evidence on six primary outcomes at 1 year after referral. Main Results: Twenty studies (14 RCTs and 6 QEDs) met our inclusion criteria. Fifteen of these studies provided some valid data for meta-analysis; these studies included 10,980 families in relevant FFT and comparison groups. All included studies had high risks of bias on at least one indicator. Half of the studies had high risks of bias on baseline equivalence, support for intent-to-treat analysis, selective reporting, and conflicts of interest. Fifteen studies had incomplete reporting of outcomes and endpoints. Using the GRADE rubric, we found that the certainty of evidence for FFT was very low for all of our primary outcomes. Using pairwise meta-analysis, we found no evidence of effects of FFT compared with other active treatments on any primary or secondary outcomes. Primary outcomes were: recidivism, out-of-home placement, internalising behaviour problems, external behaviour problems, self-reported delinquency, and drug or alcohol use. Secondary outcomes were: peer relations and prosocial behaviour, youth self esteem, parent symptoms and behaviour, family functioning, school attendance, and school performance. There were few studies in the pairwise meta-analysis (k < 7) and little heterogeneity of effects across studies in most of these analyses. There were few differences between effect estimates obtained in RCTs versus QEDs. More comprehensive CE models showed positive results of FFT in some domains and negative results in others, but these effects were small (standardised mean difference [SMD] <|0.20|) and not significantly different from no effect with one exception: Two studies found positive effects of FFT on youth substance abuse and two studies found null results in this domain, and the overall effect estimate for this outcome was statistically different from zero. Over all outcomes (15 studies and 293 effect sizes), small positive effects were detected (SMD = 0.19, SE = 0.09), but these were not significantly different from zero effect. Prediction intervals showed that future FFT evaluations are likely to produce a wide range of results, including moderate negative effects and strong positive results (-0.37 to 0.75). Authors' Conclusions: Results of 10 RCTs and five QEDs show that FFT does not produce consistent benefits or harms for youth with behavioural problems and their families. The positive or negative direction of results is inconsistent within and across studies. Most outcomes are not fully reported, the quality of available evidence is suboptimal, and the certainty of this evidence is very low. Overall estimates of effects of FFT may be inflated, due to selective reporting and publication biases.

4.
Campbell Syst Rev ; 19(2): e1332, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-37252374

RESUMEN

This is the protocol for a Campbell systematic review. The objectives are as follows: To identify methods used to assess the risk of outcome reporting bias (ORB) in studies included in recent Campbell systematic reviews of intervention effects. The review will answer the following questions: What proportion of recent Campbell reviews included assessment of ORB? How did recent reviews define levels of risk of ORB (what categories, labels, and definitions did they use)? To what extent and how did these reviews use study protocols as sources of data on ORB? To what extent and how did reviews document reasons for judgments about risk of ORB? To what extent and how did reviews assess the inter-rater reliability of ORB ratings? To what extent and how were issues of ORB considered in the review's abstract, plain language summary, and conclusions?

5.
Res Synth Methods ; 13(4): 489-507, 2022 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-35343067

RESUMEN

Missing covariates is a common issue when fitting meta-regression models. Standard practice for handling missing covariates tends to involve one of two approaches. In a complete-case analysis, effect sizes for which relevant covariates are missing are omitted from model estimation. Alternatively, researchers have employed the so-called "shifting units of analysis" wherein complete-case analyses are conducted on only certain subsets of relevant covariates. In this article, we clarify conditions under which these approaches generate unbiased estimates of regression coefficients. We find that unbiased estimates are possible when the probability of observing a covariate is completely independent of effect sizes. When that does not hold, regression coefficient estimates may be biased. We study the potential magnitude of that bias assuming a log-linear model of missingness and find that the bias can be substantial, as large as Cohen's d = 0.4-0.8 depending on the missingness mechanism.


Asunto(s)
Interpretación Estadística de Datos , Sesgo , Modelos Lineales , Probabilidad
6.
Alcohol Alcohol ; 57(1): 35-46, 2022 Jan 08.
Artículo en Inglés | MEDLINE | ID: mdl-33550367

RESUMEN

OBJECTIVES: In this tutorial, we examine methods for exploring missingness in a dataset in ways that can help to identify the sources and extent of missingness, as well as clarify gaps in evidence. METHODS: Using raw data from a meta-analysis of substance abuse interventions, we demonstrate the use of exploratory missingness analysis (EMA) including techniques for numerical summaries and visual displays of missing data. RESULTS: These techniques examine the patterns of missing covariates in meta-analysis data and the relationships among variables with missing data and observed variables including the effect size. The case study shows complex relationships among missingness and other potential covariates in meta-regression, highlighting gaps in the evidence base. CONCLUSION: Meta-analysts could often benefit by employing some form of EMA as they encounter missing data.

9.
Psychol Bull ; 134(4): 498-500; discussion 501-3, 2008 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-18605816

RESUMEN

In this comment on C. F. Bond and B. M. DePaulo, the authors raise methodological concerns about the approach used to analyze the data. The authors suggest further refinement of the procedures used, and they compare the approach taken by Bond and DePaulo with standard methods for meta-analysis.


Asunto(s)
Decepción , Individualidad , Juicio/fisiología , Metaanálisis como Asunto , Humanos , Variaciones Dependientes del Observador , Psicometría/métodos , Análisis de Regresión , Reproducibilidad de los Resultados , Conducta Social
10.
Psychol Methods ; 9(4): 426-45, 2004 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-15598097

RESUMEN

Calculation of the statistical power of statistical tests is important in planning and interpreting the results of research studies, including meta-analyses. It is particularly important in moderator analyses in meta-analysis, which are often used as sensitivity analyses to rule out moderator effects but also may have low statistical power. This article describes how to compute statistical power of both fixed- and mixed-effects moderator tests in meta-analysis that are analogous to the analysis of variance and multiple regression analysis for effect sizes. It also shows how to compute power of tests for goodness of fit associated with these models. Examples from a published meta-analysis demonstrate that power of moderator tests and goodness-of-fit tests is not always high.


Asunto(s)
Metaanálisis como Asunto , Modelos Psicológicos , Humanos
11.
J Pediatr Nurs ; 19(4): 247-56, 2004 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-15308974

RESUMEN

Asthma is a chronic illness that affects 5% to 10% or about 5 million children in this country. Morbidity and rising mortality rates are of particular concern in minority children. This study addresses a serious knowledge deficit about the management of asthma in minority children by testing the effect of a school-based asthma education program on psychosocial and health outcomes of 8-13-year-old inner-city minority students. Although the mean scores of the treatment group were higher than the control group on several of the psychosocial measures, these changes were not significant. However, significant differences were found between the groups on health outcomes. Recommendations for future research and clinical practice are discussed.


Asunto(s)
Asma/enfermería , Asma/prevención & control , Negro o Afroamericano/estadística & datos numéricos , Educación en Salud/normas , Conocimientos, Actitudes y Práctica en Salud , Servicios de Salud Escolar/normas , Autocuidado/métodos , Adolescente , Asma/diagnóstico , Asma/etnología , Niño , Estado de Salud , Humanos , Medio Oeste de Estados Unidos/epidemiología , Evaluación de Resultado en la Atención de Salud , Pobreza , Factores de Riesgo , Servicios de Salud Escolar/estadística & datos numéricos , Encuestas y Cuestionarios , Factores de Tiempo , Salud Urbana/estadística & datos numéricos , Servicios Urbanos de Salud/normas
12.
J Nurs Meas ; 12(1): 7-19, 2004.
Artículo en Inglés | MEDLINE | ID: mdl-15916316

RESUMEN

Accurate evaluation of asthma self-efficacy is essential to the effective management of asthma. This article describes the development and testing of the Asthma Belief Survey (ABS). The instrument is a 15-item tool that uses a 5-point self-report scale to measure asthma self-efficacy in relation to daily asthma maintenance and an asthma crisis. This instrument was tested with a sample of 79 African American school children, who attended eight inner-city elementary schools. The mean age of the sample was 11.05 years with a range of 8 to 14 years. The majority of students had been diagnosed with asthma prior to the age of 5 years. The Asthma Belief Survey demonstrated good psychometric properties: good Cronbach's alpha reliability coefficient (.83), coherence as a single scale measuring children's self-efficacy in treating their own asthma, and significant relationships with scales of asthma knowledge (r = .51, p < .000) and asthma self-care practices (r = .52, p < .001). The Asthma Belief Survey has sound reliability and validity evidence to support its use to measure a child's asthma self-management self-efficacy. The practitioner can use this instrument to assess a child's self-efficacy in the areas of asthma health maintenance and avoidance of asthma episodes.


Asunto(s)
Asma/etnología , Negro o Afroamericano , Encuestas Epidemiológicas , Autocuidado/psicología , Autoeficacia , Encuestas y Cuestionarios , Adolescente , Negro o Afroamericano/psicología , Asma/psicología , Niño , Femenino , Humanos , Masculino , Áreas de Pobreza , Psicometría , Reproducibilidad de los Resultados , Estados Unidos
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