Search

In developing products for rare diseases, statistical challenges arise due to the limited number of patients available for participation in drug trials and other clinical research. Bayesian adaptive clinical trial designs offer the possibility of increased statistical efficiency, reduced development cost and ethical hazard prevention via their incorporation of evidence from external sources (historical data, expert opinions, and real-world evidence), and flexibility in the specification of interim looks. In this paper, we propose a novel Bayesian adaptive commensurate design that borrows adaptively from historical information and also uses a particular payoff function to optimize the timing of the study's interim analysis. The trial payoff is a function of how many samples can be saved via early stopping and the probability of making correct early decisions for either futility or efficacy. We calibrate our Bayesian algorithm to have acceptable long-run frequentist properties (Type I error and power) via simulation at the design stage. We illustrate our approach using a pediatric trial design setting testing the effect of a new drug for a rare genetic disease. The optimIA R package available at https://github.com/wxwx1993/Bayesian_IA_Timing provides an easy-to-use implementation of our approach. [ABSTRACT FROM AUTHOR]

Copyright of Developmental Medicine & Child Neurology is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Aim: To characterize fatigue in children with hemiparesis with perinatal stroke and explore associations with measures of motor performance and corticospinal excitability.Method: Forty-five children (16 females, 29 males), aged 6 to 18 years (mean [SD] 12y [4]), with magnetic resonance imaging-confirmed perinatal stroke participated. Associations between fatigue (Pediatric Quality of Life Inventory Version 3.0 cerebral palsy module fatigue subscale), motor performance (Assisting Hand Assessment [AHA], Box and Blocks Test, grip strength), and excitability of corticospinal projections to both hands were examined using ranked tests of correlation, robust regression, and the Mann-Whitney U test.Results: Nearly half of the participants (n=21) reported experiencing fatigue in the previous month. Function in the less affected hand (Box and Blocks Test, grip strength) was correlated with fatigue scores. Participants with preserved ipsilateral projections to the more affected hand had less fatigue, and scores correlated with the excitability of these projections. Fatigue scores were not associated with age, sex, or AHA score.Interpretation: Fatigue is common in children with hemiparesis with perinatal stroke and is associated with motor performance and the presence and excitability of ipsilateral corticospinal projections from the contralesional hemisphere to the more affected hand.What This Paper Adds: Fatigue is common in children with hemiparesis with perinatal stroke. Fatigue was associated with motor performance and strength in the less affected, but not the more affected, hand. Fatigue was associated with the presence and excitability of ipsilateral corticospinal projections from the contralesional hemisphere. [ABSTRACT FROM AUTHOR]

Copyright of Developmental Medicine & Child Neurology is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Developmental Medicine & Child Neurology is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Objective: The use of relative and absolute effect estimates has important implications for the interpretation of study findings. Likewise, examining additive and multiplicative interaction can lead to differing conclusions about the joint effects of two exposure variables. The aim of this paper is to examine the relationship between BMI and mortality on the relative and absolute scales and investigate interaction between BMI and age.Methods: Data from 68,132 participants in the Women's Health Initiative (WHI) study were used. The risk ratio and risk difference of BMI on mortality were estimated. A product term was also included to examine interaction between BMI and age on the multiplicative scale, and the relative excess risk of interaction was calculated to measure additive interaction.Results: Results demonstrated that the mortality risk ratio decreased as women aged, but the mortality risk difference increased as women aged. Evidence of additive and multiplicative interaction between age and BMI was found.Conclusions: In postmenopausal women, the relative mortality risk associated with high BMI decreased with increasing age, but the absolute risk of high BMI increased with increasing age. This indicates the importance of considering the interaction between age and BMI to understand mortality risk in older women. [ABSTRACT FROM AUTHOR]

Copyright of Developmental Medicine & Child Neurology is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Developmental Medicine & Child Neurology is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Developmental Medicine & Child Neurology is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Developmental Medicine & Child Neurology is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Aim: To evaluate the reliability and validity of the Children's Visual Impairment Test for 3- to 6-year-olds (CVIT 3-6).Method: Reliability was assessed via test-retest correlation and intraclass correlation coefficient (ICC) in typically developing children, children with cerebral visual impairment (CVI), intellectual impairment, and simulated impaired vision (validation groups n=59, mean developmental age=4y 10mo, 27 females, 32 males). Internal validity was evaluated with a confirmatory factor analysis on the normative sample (n=301, median age=4y 8mo, SD=9.7mo, 148 females, 153 males). External validity was assessed by correlating performance on CVIT 3-6 with L94, the Beery-Buktenica Developmental Test of Visuo-Motor Integration (Beery-VMI), the Freiburg Vision Test, the revised Snijders-Oomen Nonverbal Intelligence Test for children between 2 years 6 months and 7-years-old (SON-R 2.5-7), and the Social Responsiveness Scale (SRS) questionnaire and by comparing performance between validation groups.Results: We observed very good test-retest reliability (r=0.82, p<0.001, ICC=0.80) and confirmed the hypothesized factor structure (comparative fit index=1; Tucker-Lewis index=1.045). We found high correlations with tests with a strong visual perception component (L94: r=0.74, p<0.001; SON-R 2.5-7: r=0.37, p=0.01) and low correlations with other tests (Beery-VMI: r=0.25, p=0.09; SRS: r=0-0.26, p=0.09). Lowest scores were observed for children with CVI compared to the other validation groups (F[3,44]=5.1, p=0.003).Interpretation: CVIT 3-6 is grounded in knowledge of visual perception. The tool specifically measures CVI-related visual perception deficits and is not mediated by intellectual abilities or low visual acuity.What the Paper Adds: Evidence for good test-retest reliability of the Children's Visual Impairment Test for 3- to 6-year-olds (CVIT 3-6). Factor structure of normative data reflects CVIT 3-6's foundations in vision science. CVIT 3-6 specifically measures visual perception impairments. CVIT 3-6 performance is not influenced by intelligence or low visual acuity. [ABSTRACT FROM AUTHOR]

Copyright of Developmental Medicine & Child Neurology is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Aim: This paper aimed to analyse the association between small for size at birth, stunting, recovery from stunting and pubertal development in a rural Bangladeshi cohort.Methods: The participants were 994 girls and 987 boys whose mothers participated in the Maternal and Infant Nutrition Interventions in Matlab trial. The birth cohort was followed from birth to puberty 2001-2017. Pubertal development according to Tanner was self-assessed. Age at menarche was determined and in boys, consecutive height measurements were used to ascertain whether pubertal growth spurt had started. The exposures and outcomes were modelled by Cox's proportional hazards analyses and logistic regression.Results: There was no difference in age at menarche between girls that were small or appropriate for gestational age at birth. Boys born small for gestational age entered their pubertal growth spurt later than those with appropriate weight. Children who were stunted had later pubertal development, age at menarche and onset of growth spurt than non-stunted children. Children who recovered from infant or early childhood stunting had similar pubertal development as non-stunted children.Conclusion: Infant and childhood stunting was associated with a later pubertal development. Recovery from stunting was not associated with earlier puberty in comparison with non-stunted children. [ABSTRACT FROM AUTHOR]

The literature about Prediction Interval (PI) and Tolerance Interval (TI) in linear mixed models is usually developed for specific designs, which is a main limitation to their use. This paper proposes to reformulate the two-sided PI to be generalizable under a wide variety of designs (one random factor, nested and crossed designs for multiple random factors, and balanced or unbalanced designs). This new methodology is based on the Hessian matrix, namely, the inverse of (observed) Fisher Information matrix, and is built with a cell mean model. The degrees of freedom for the total variance are calculated with the generalized Satterthwaite method and compared to the Kenward-Roger's degrees of freedom for fixed effects. Construction of two-sided TIs are also detailed with one random factor, and two nested and two crossed random variables. An extensive simulation study is carried out to compare the widths and coverage probabilities of Confidence Intervals (CI), PIs, and TIs to their nominal levels. It shows excellent coverage whatever the design and the sample size are. Finally, these CIs, PIs, and TIs are applied to two real data sets: one from orthopedic surgery study (intralesional resection risk) and the other from assay validation study during vaccine development. [ABSTRACT FROM AUTHOR]

Objective: Suicide is a leading cause of death, yet the accurate prediction of suicidal behavior is an elusive target for clinicians and researchers. The current paper examines the predictive validity of the Mini Neuropsychiatric Interview (MINI) Suicidality subscale for suicide attempts (SAs) for a homeless population with mental illness.Methods: Two thousand two hundred and fifty-five homeless individuals with mental illness across five Canadian cities enrolled in the At Home/Chez Soi Housing First trial interviewed at baseline using the MINI Suicidality subscale with 2-year follow-up of self-reported SAs.Results: Two thousand two hundred and twenty-one participants were included in the analysis. High rates of mood and substance use disorders were present (56.5% and 67.4%, respectively). The mean MINI Suicidality subscale score was 7.71. Among 1,700 participants with follow-up data, 11.4% reported a SA over the 2-year study period. MINI Suicidality subscale scores were predictive of SAs (AUC ≥ 0.70) among those with and without a history of SAs, even among those with missing answers. A positive predictive value of 0.20 and a negative predictive value of 0.95 were demonstrated, with a relatively low number needed to assess of 4.5-5.Conclusion: The MINI Suicidal subscale shows promise as an easy to use and accurate suicide risk prediction tool among homeless individuals with mental illness. [ABSTRACT FROM AUTHOR]

Newborn infants are among those most severely affected by humanitarian crises. Aid organisations increasingly recognise the necessity to provide for the medical needs of newborns, however, this may generate distinctive ethical questions for those providing humanitarian medical care. Medical ethical approaches to neonatal care familiar in other settings may not be appropriate given the diversity and volatility of humanitarian disasters, and the extreme resource limitations commonly faced by humanitarian aid missions. In this paper, we first systematically review existing guidelines relating to the treatment and resuscitation of newborns in humanitarian crises, finding little substantive ethical guidance for those providing humanitarian healthcare. We next draw on paradigm cases and published literature to identify and describe some of the major ethical questions common to these settings. We divide these questions into quality of life considerations, allocation of limited resources, and conflicting cultural norms and values. We finally suggest some preliminary recommendations to guide ethical decision-making around resuscitation of newborns and withdrawal of treatment in humanitarian settings. [ABSTRACT FROM AUTHOR]

Cox proportional hazard regression model is a popular tool to analyze the relationship between a censored lifetime variable with other relevant factors. The semiparametric Cox model is widely used to study different types of data arising from applied disciplines such as medical science, biology, and reliability studies. A fully parametric version of the Cox regression model, if properly specified, can yield more efficient parameter estimates, leading to better insight generation. However, the existing maximum likelihood approach of generating inference under the fully parametric proportional hazards model is highly nonrobust against data contamination (often manifested through outliers), which restricts its practical usage. In this paper, we develop a robust estimation procedure for the parametric proportional hazards model based on the minimum density power divergence approach. The proposed minimum density power divergence estimator is seen to produce highly robust estimates under data contamination with only a slight loss in efficiency under pure data. Further, it is always seen to generate more precise inference than the likelihood based estimates under the semiparametric Cox models or their existing robust versions. We also justify their robustness theoretically through the influence function analysis. The practical applicability and usefulness of the proposal are illustrated through simulations and real data examples. [ABSTRACT FROM AUTHOR]

In many applications of linear mixed-effects models to longitudinal and multilevel data especially from medical studies, it is of interest to test for the need of random effects in the model. It is known that classical tests such as the likelihood ratio, Wald, and score tests are not suitable for testing random effects because they suffer from testing on the boundary of the parameter space. Instead, permutation and bootstrap tests as well as Bayesian tests, which do not rely on the asymptotic distributions, avoid issues with the boundary of the parameter space. In this paper, we first develop a permutation test based on the likelihood ratio test statistic, which can be easily used for testing multiple random effects and any subset of them in linear mixed-effects models. The proposed permutation test would be an extension to two existing permutation tests. We then aim to compare permutation tests and Bayesian tests for random effects to find out which test is more powerful under which situation. Nothing is known about this in the literature, although this is an important practical problem due to the usefulness of both methods in tackling the challenges with testing random effects. For this, we consider a Bayesian test developed using Bayes factors, where we also propose a new alternative computation for this Bayesian test to avoid some computational issue it encounters in testing multiple random effects. Extensive simulations and a real data analysis are used for evaluation of the proposed permutation test and its comparison with the Bayesian test. We find that both tests perform well, albeit the permutation test with the likelihood ratio statistic tends to provide a relatively higher power when testing multiple random effects. [ABSTRACT FROM AUTHOR]

Standard methods for two-sample tests such as the t-test and Wilcoxon rank sum test may lead to incorrect type I errors when applied to longitudinal or clustered data. Recent alternatives of two-sample tests for clustered data often require certain assumptions on the correlation structure and/or noninformative cluster size. In this paper, based on a novel pseudolikelihood for correlated data, we propose a score test without knowledge of the correlation structure or assuming data missingness at random. The proposed score test can capture differences in the mean and variance between two groups simultaneously. We use projection theory to derive the limiting distribution of the test statistic, in which the covariance matrix can be empirically estimated. We conduct simulation studies to evaluate the proposed test and compare it with existing methods. To illustrate the usefulness proposed test, we use it to compare self-reported weight loss data in a friends' referral group, with the data from the Internet self-joining group. [ABSTRACT FROM AUTHOR]

Copyright of Developmental Medicine & Child Neurology is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Aim: To determine the mortality rate, immediate cause of death (CoD), and predictors of death in children with cerebral palsy (CP) in rural Bangladesh.Method: We carried out a prospective population-based surveillance study of children with CP aged 0 to 18 years registered with the Bangladesh Cerebral Palsy Register (BCPR) between January 2015 and December 2016, with subsequent follow-up until December 2017. Verbal autopsy was applied to assign immediate CoD. Crude mortality rates, hazard ratios of death, and survival probabilities were estimated.Results: Twenty-nine of the 678 children in the BCPR died during the study period, resulting in a crude mortality rate of 19.5 per 1000 person-years of observation (total follow-up duration 1486.8 person-years; mean 2y [standard deviation 6mo]). The leading immediate CoD was meningitis (n=9) and pneumonia (n=8). Survival probability and hazard ratio of death was significantly associated with age, Gross Motor Functional Classification System level, and associated impairments. Severe underweight and/or severe stunting was significantly overrepresented among deceased children than others in the cohort (p<0.05) when compared with the World Health Organization reference population.Interpretation: The majority of deaths were due to potentially preventable causes. The life expectancy of these children could have been extended by ensuring primary healthcare and nutritional supplementation.What This Paper Adds: Mortality rate in children with cerebral palsy (CP) in rural Bangladesh is 19.5 per 1000 person-years. The majority of children with CP died from potentially preventable and treatable conditions. Motor severity, associated impairments, and malnutrition make children with CP vulnerable to premature death in rural Bangladesh. [ABSTRACT FROM AUTHOR]

Copyright of Developmental Medicine & Child Neurology is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Are individuals willing to intervene in public violence? Half a century of research on the "bystander effect" suggests that the more bystanders present at an emergency, the less likely each of them is to provide help. However, recent meta-analytical evidence questions whether this effect generalizes to violent emergencies. Besides the number of bystanders present, an alternative line of research suggests that pre-existing social relations between bystanders and conflict participants are important for explaining whether bystanders provide help. The current paper offers a rare comparison of both factors-social relations and the number of bystanders present-as predictors of bystander intervention in real-life violent emergencies. We systematically observed the behavior of 764 bystanders across 81 violent incidents recorded by surveillance cameras in Copenhagen, Denmark. Bystanders were sampled with a case-control design, their behavior was observed and coded, and the probability of intervention was estimated with multilevel regression analyses. The results confirm our predicted association between social relations and intervention. However, rather than the expected reversed bystander effect, we found a classical bystander effect, as bystanders were less likely to intervene with increasing bystander presence. The effect of social relations on intervention was larger in magnitude than the effect of the number of bystanders. We assess these findings in light of recent discussions about the influence of group size and social relations in human helping. Further, we discuss the utility of video data for the assessment of real-life bystander behavior. [ABSTRACT FROM AUTHOR]

Among several semiparametric models, the Cox proportional hazard model is widely used to assess the association between covariates and the time-to-event when the observed time-to-event is interval-censored. Often, covariates are measured with error. To handle this covariate uncertainty in the Cox proportional hazard model with the interval-censored data, flexible approaches have been proposed. To fill a gap and broaden the scope of statistical applications to analyze time-to-event data with different models, in this paper, a general approach is proposed for fitting the semiparametric linear transformation model to interval-censored data when a covariate is measured with error. The semiparametric linear transformation model is a broad class of models that includes the proportional hazard model and the proportional odds model as special cases. The proposed method relies on a set of estimating equations to estimate the regression parameters and the infinite-dimensional parameter. For handling interval censoring and covariate measurement error, a flexible imputation technique is used. Finite sample performance of the proposed method is judged via simulation studies. Finally, the suggested method is applied to analyze a real data set from an AIDS clinical trial. [ABSTRACT FROM AUTHOR]

Epidemiologic research often aims to estimate the association between a binary exposure and a binary outcome, while adjusting for a set of covariates (eg, confounders). When data are clustered, as in, for instance, matched case-control studies and co-twin-control studies, it is common to use conditional logistic regression. In this model, all cluster-constant covariates are absorbed into a cluster-specific intercept, whereas cluster-varying covariates are adjusted for by explicitly adding these as explanatory variables to the model. In this paper, we propose a doubly robust estimator of the exposure-outcome odds ratio in conditional logistic regression models. This estimator protects against bias in the odds ratio estimator due to misspecification of the part of the model that contains the cluster-varying covariates. The doubly robust estimator uses two conditional logistic regression models for the odds ratio, one prospective and one retrospective, and is consistent for the exposure-outcome odds ratio if at least one of these models is correctly specified, not necessarily both. We demonstrate the properties of the proposed method by simulations and by re-analyzing a publicly available dataset from a matched case-control study on induced abortion and infertility. [ABSTRACT FROM AUTHOR]

The relative risk, risk difference, and odds ratio are three major indices of differences in risks of diseases between different groups. Although widely used in research and practice in biomedical and epidemiologic research, misconceptions are not uncommon about their relationships. Many publications offer contradicting advices in how to use them in studies. Some biomedical researchers believe that these indices are related in a monotone fashion, and, thus, changes in one direction in one of the indices can be interpreted as same directional changes in the other two. Misconceptions about these three indices such as the monotone relationship are so prevalent in the biomedical and epidemiologic research that clarifications of such popular beliefs are warranted. In this paper, we take a systematic approach to characterize the relationships among the indices. We develop key results to elucidate the intricate relationships between the indices. Our findings speak to the need for investigators to carefully consider the different indices before using them in their studies, since they are not interchangeable and results based on one index are generally not translatable into any of the others. [ABSTRACT FROM AUTHOR]

The proportional subdistribution hazard regression model has been widely used by clinical researchers for analyzing competing risks data. It is well known that quantile regression provides a more comprehensive alternative to model how covariates influence not only the location but also the entire conditional distribution. In this paper, we develop variable selection procedures based on penalized estimating equations for competing risks quantile regression. Asymptotic properties of the proposed estimators including consistency and oracle properties are established. Monte Carlo simulation studies are conducted, confirming that the proposed methods are efficient. A bone marrow transplant data set is analyzed to demonstrate our methodologies. [ABSTRACT FROM AUTHOR]

Introduction: Short-form versions of the Montreal Cognitive Assessment (SF-MoCA) are increasingly used to screen for dementia in research and practice. We sought to collate evidence on the accuracy of SF-MoCAs and to externally validate these assessment tools.Methods: We performed systematic literature searching across multidisciplinary electronic literature databases, collating information on the content and accuracy of all published SF-MoCAs. We then validated all the SF-MoCAs against clinical diagnosis using independent stroke (n = 787) and memory clinic (n = 410) data sets.Results: We identified 13 different SF-MoCAs (21 studies, n = 6477 participants) with differing test content and properties. There was a pattern of high sensitivity across the range of SF-MoCA tests. In the published literature, for detection of post stroke cognitive impairment, median sensitivity across included studies: 0.88 (range: 0.70-1.00); specificity: 0.70 (0.39-0.92). In our independent validation using stroke data, median sensitivity: 0.99 (0.80-1.00); specificity: 0.40 (0.14-0.87). To detect dementia in older adults, median sensitivity: 0.88 (0.62-0.98); median specificity: 0.87 (0.07-0.98) in the literature and median sensitivity: 0.96 (range: 0.72-1.00); median specificity: 0.36 (0.14-0.86) in our validation. Horton's SF-MoCA (delayed recall, serial subtraction, and orientation) had the most favorable properties in stroke (sensitivity: 0.90, specificity: 0.87, positive predictive value [PPV]: 0.55, and negative predictive value [NPV]: 0.93), whereas Cecato's "MoCA reduced" (clock draw, animal naming, delayed recall, and orientation) performed better in the memory clinic (sensitivity: 0.72, specificity: 0.86, PPV: 0.55, and NPV: 0.93).Conclusions: There are many published SF-MoCAs. Clinicians and researchers using a SF-MoCA should be explicit about the content. For all SF-MoCA, sensitivity is high and similar to the full scale suggesting potential utility as an initial cognitive screening tool. However, choice of SF-MoCA should be informed by the clinical population to be studied. [ABSTRACT FROM AUTHOR]

Objective: Slowing functional decline could enable people living with dementia to live for longer and more independently in their own homes. We aimed to update previous syntheses examining the effectiveness of nonpharmacological interventions in reducing functional decline (activities of daily living, activity-specific physical functioning, or function-specific goal attainment) in people living in their own homes with dementia.Methods: We systematically searched electronic databases from January 2012 to May 2018; two researchers independently rated risk of bias of randomised controlled trials (RCTs) fitting predetermined inclusion criteria using a checklist; we narratively synthesised findings, prioritising studies judged to have a lower risk of bias.Results: Twenty-nine papers (describing 26 RCTs) met eligibility criteria, of which we judged 13 RCTs to have a lower risk of bias. Study interventions were evaluated in four groups: physical exercise, occupational, multicomponent, and cognition-oriented interventions. Four out of 13 RCTs reported functional ability as a primary outcome. In studies judged to have a lower risk of bias, in-home tailored exercise, individualised cognitive rehabilitation, and in-home activities-focussed occupational therapy significantly reduced functional decline relative to control groups in individual studies. There was consistent evidence from studies at low risk of bias that group-based exercise and reminiscence therapies were ineffective at reducing functional decline.Conclusion: We found no replicated evidence of intervention effectiveness in decreasing functional decline. Interventions associated with slower functional decline in individual trials have been individually delivered and tailored to the needs of the person with dementia. This is consistent with previous findings. Future intervention trials should prioritise these approaches. [ABSTRACT FROM AUTHOR]

Background: The incidence of a peri-implant soft tissue dehiscence/deficiency (PSTD) is not a rare finding. Despite multiple previous attempts aimed at correcting the PSTDs, a classification of these conditions has not yet been proposed. This lack in the literature may also lead to discrepancies in the reported treatment outcomes and thus misinform the clinician or the readers. The aim of the present article was therefore to present a classification of peri-implant PSTD at a single implant site.Methods: Four classes of PSTDs were discussed based on the position of the gingival margin of the implant-supported crown in relation to the homologous natural tooth. In addition, the bucco-lingual position of the implant head was also taken into consideration. Each class was further subdivided based on the height of the anatomical papillae.Results: Subsequently, for each respective category a surgical approach (including bilaminar techniques, the combined prosthetic-surgical approach or soft tissue augmentation with a submerged healing) was also suggested.Conclusion: This paper provides a new classification system for describing PSTDs at single implant sites, with the appropriate recommended treatment protocol. [ABSTRACT FROM AUTHOR]

Copyright of Developmental Medicine & Child Neurology is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Developmental Medicine & Child Neurology is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Developmental Medicine & Child Neurology is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Developmental Medicine & Child Neurology is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Developmental Medicine & Child Neurology is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Analyzing safety data from clinical trials to detect safety signals worth further examination involves testing multiple hypotheses, one for each observed adverse event (AE) type. There exists certain hierarchical structure for these hypotheses due to the classification of the AEs into system organ classes, and these AEs are also likely correlated. Many approaches have been proposed to identify safety signals under the multiple testing framework and tried to achieve control of false discovery rate (FDR). The FDR control concerns the expectation of the false discovery proportion (FDP). In practice, the control of the actual random variable FDP could be more relevant and has recently drawn much attention. In this paper, we proposed a two-stage procedure for safety signal detection with direct control of FDP, through a permutation-based approach for screening groups of AEs and a permutation-based approach of constructing simultaneous upper bounds for false discovery proportion. Our simulation studies showed that this new approach has controlled FDP. We demonstrate our approach using data sets derived from a drug clinical trial. [ABSTRACT FROM AUTHOR]

In this paper, we derive the joint distribution of progression-free and overall survival as a function of transition probabilities in a multistate model. No assumptions on copulae or latent event times are needed and the model is allowed to be non-Markov. From the joint distribution, statistics of interest can then be computed. As an example, we provide closed formulas and statistical inference for Pearson's correlation coefficient between progression-free and overall survival in a parametric framework. The example is inspired by recent approaches to quantify the dependence between progression-free survival, a common primary outcome in Phase 3 trials in oncology and overall survival. We complement these approaches by providing methods of statistical inference while at the same time working within a much more parsimonious modeling framework. Our approach is completely general and can be applied to other measures of dependence. We also discuss extensions to nonparametric inference. Our analytical results are illustrated using a large randomized clinical trial in breast cancer. [ABSTRACT FROM AUTHOR]

When several types of recurrent events may arise, interest often lies in marginal modeling and studying the nature of the dependence structure. In this paper, we propose a multivariate mixed-Poisson model with the dependence between events accommodated by type-specific random effects which are associated through use of a Gaussian copula. Such models retain marginal features with a simple interpretation, reflect the heterogeneity in risk for each type of event, and provide insight into the dependence between the different types of events. Semiparametric inference is proposed based on composite likelihood to avoid high dimensional integration. An application to a study of nutritional supplements in malnourished children is given in which the goal is to evaluate the reduction in the rate of several different kinds of infection. [ABSTRACT FROM AUTHOR]

Bayesian adaptive designs have become popular because of the possibility of increasing the number of patients treated with more beneficial treatments, while still providing sufficient evidence for treatment efficacy comparisons. It can be essential, for regulatory and other purposes, to conduct frequentist analyses both before and after a Bayesian adaptive trial, and these remain challenging. In this paper, we propose a general simulation-based approach to compare frequentist designs with Bayesian adaptive designs based on frequentist criteria such as power and to compute valid frequentist p-values. We illustrate our approach by comparing the power of an equal randomization (ER) design with that of an optimal Bayesian adaptive (OBA) design. The Bayesian design considered here is the dynamic programming solution of the optimization of a specific utility function defined by the number of successes in a patient horizon, including patients whose treatment will be affected by the trial's results after the end of the trial. While the power of an ER design depends on treatment efficacy and the sample size, the power of the OBA design also depends on the patient horizon size. Our results quantify the trade-off between power and the optimal assignment of patients to treatments within the trial. We show that, for large patient horizons, the two criteria are in agreement, while for small horizons, differences can be substantial. This has implications for precision medicine, where patient horizons are decreasing as a result of increasing stratification of patients into subpopulations defined by molecular markers. [ABSTRACT FROM AUTHOR]

Wearable device technology allows continuous monitoring of biological markers and thereby enables study of time-dependent relationships. For example, in this paper, we are interested in the impact of daily energy expenditure over a period of time on subsequent progression toward obesity among children. Data from these devices appear as either sparsely or densely observed functional data and methods of functional regression are often used for their statistical analyses. We study the scalar-on-function regression model with imprecisely measured values of the predictor function. In this setting, we have a scalar-valued response and a function-valued covariate that are both collected at a single time period. We propose a generalized method of moments-based approach for estimation, while an instrumental variable belonging in the same time space as the imprecisely measured covariate is used for model identification. Additionally, no distributional assumptions regarding the measurement errors are assumed, while complex covariance structures are allowed for the measurement errors in the implementation of our proposed methods. We demonstrate that our proposed estimator is L2 consistent and enjoys the optimal rate of convergence for univariate nonparametric functions. In a simulation study, we illustrate that ignoring measurement error leads to biased estimations of the functional coefficient. The simulation studies also confirm our ability to consistently estimate the function-valued coefficient when compared to approaches that ignore potential measurement errors. Our proposed methods are applied to our motivating example to assess the impact of baseline levels of energy expenditure on body mass index among elementary school-aged children. [ABSTRACT FROM AUTHOR]

Accessible summary: Sleep hygiene education (SHE) is a "behavioural" intervention which helps parents create the best sleeping conditions for their child. It is often used to improve sleep problems that children with developmental disabilities have.SHE includes advice around creating bedtime routines, creating a calming bedroom environment and eating healthily. Lots of health and social care professionals use SHE, but there are not many research papers which show the best way to support parents to try out the advice.This research tells the story of nine parents and eleven professionals who have used SHE to help improve children's sleep problems.Their experiences are important in the research literature and will help services such as community children's learning disability teams improve the way SHE is used in the future. Background: Sleep hygiene education (SHE) is a familiar intervention for addressing behavioural sleep problems in children with developmental disabilities that involves advising parents on sleep‐promoting behaviours; however, it is supported by a limited evidence base. Materials and methods: This exploratory study aimed to enhance qualitative understanding and explore stakeholder perceptions about experience, current practice and ideas around the implementation of SHE. Parents of children with developmental disabilities and sleep problems (N = 9) and sleep practitioners (N = 11) took part in semi‐structured interviews and focus groups, and data were thematically analysed. Results and discussion: The analysis identified four parent themes: Beliefs about sleep problems; Getting professional help; Ways of knowing about sleep; and Visions of sleep support. Two practitioner themes were also identified: Sleep service accessibility and Inconsistent sleep support. Conclusion: The findings provide further insight into how parents of children with developmental disabilities experience sleep problems, and how SHE is currently implemented. These have implications for both policy and practice. [ABSTRACT FROM AUTHOR]

The present study describes the development and validation of a new instrument to measure the well‐being of Indonesian people. Items were generated by taking into account the recent cross‐cultural developments in the literature. Participants (N = 1,028) from a number of provinces in Indonesia completed an online or a paper questionnaire containing a battery of measures, including the new well‐being instrument. The total sample was randomly split into two equal groups. An exploratory factor analysis (n = 516) was conducted on one half to explore the factor structure of the new scale, which resulted in a 24‐item scale with a four‐factor solution. The four factors were (a) Basic Needs, (b) Social Relation, (c) Acceptance, and (d) Spirituality. A confirmatory factor analysis was conducted on the second half (n = 516), which confirmed the four‐factor structure with 20 items emerging as the best and most parsimonious fit of the data. The psychometric properties of the final scale were tested on the whole sample. The new scale displayed sound internal consistency, test‐retest reliability, and divergent, convergent, and discriminant validity. The scale has the potential to be used in future research which examines well‐being in the Indonesia context. Future directions and limitations of the study are discussed. [ABSTRACT FROM AUTHOR]

Although research on the experiences of unaccompanied asylum‐seeking young people in the UK has grown steadily in recent years, their experience of fostering and of the role played by foster carers in helping their adjustment have been neglected. This paper reports findings from the first UK study into these experiences, describing issues arising from initial assessment and preparation for fostering and the ways in which young people and foster carers adjusted to their lives together. It assesses the progress made by young people during placement, the strategies that appeared helpful to relationship building, and the extent to which young people had become integrated within the wider network of family relationships. Given that most young people first arrive as teenagers, it also considers the ways in which foster carers and social workers helped young people prepare for adult life in the context of uncertainties arising from the asylum process. [ABSTRACT FROM AUTHOR]

In this series we address important topics for emergency clinicians who either participate in research as part of their work, or use the knowledge generated by research studies. Emergency clinicians are routinely in the position of applying new evidence in clinical practice. With an ever‐increasing volume of evidence generated, this can be problematic when studies are conducted in different settings, and include different patient groups, different interventions and different outcomes. This is made even more difficult when the results of primary research studies do not agree. Systematic reviews are becoming increasingly valuable as they appraise and synthesise research findings using a clear methodology, and summarise the results of primary studies. As such, systematic reviews help translate research findings into clinical practice. This paper provides a practical starting point for understanding the steps involved in conducting a systematic review in emergency medicine and will help readers appraise the findings of systematic reviews. [ABSTRACT FROM AUTHOR]

The literature on causal effect estimation tends to focus on the population mean estimand, which is less informative as medical treatments are becoming more personalized and there is increasing awareness that subpopulations of individuals may experience a group-specific effect that differs from the population average. In fact, it is possible that there is underlying systematic effect heterogeneity that is obscured by focusing on the population mean estimand. In this context, understanding which covariates contribute to this treatment effect heterogeneity (TEH) and how these covariates determine the differential treatment effect (TE) is an important consideration. Towards such an understanding, this paper briefly reviews three approaches used in making causal inferences and conducts a simulation study to compare these approaches according to their performance in an exploratory evaluation of TEH when the heterogeneous subgroups are not known a priori. Performance metrics include the detection of any heterogeneity, the identification and characterization of heterogeneous subgroups, and unconfounded estimation of the TE within subgroups. The methods are then deployed in a comparative effectiveness evaluation of drug-eluting versus bare-metal stents among 54 099 Medicare beneficiaries in the continental United States admitted to a hospital with acute myocardial infarction in 2008. [ABSTRACT FROM AUTHOR]

Copyright of Developmental Medicine & Child Neurology is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Developmental Medicine & Child Neurology is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Developmental Medicine & Child Neurology is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Developmental Medicine & Child Neurology is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Developmental Medicine & Child Neurology is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)