Not exact matches
In future updates, we will use fixed -
effect meta - analysis for combining data where it is reasonable to assume that studies are
estimating the same underlying
treatment effect: i.e. where trials are examining the same intervention, and the trials» populations and methods are judged sufficiently similar.
The results were presented as the average
treatment effect with 95 % confidence intervals, and the
estimates of Tau ² and I ².
This is likely to have diluted overall
treatment effects but these
estimates may be more appropriate given the possibility of response bias and the increased likelihood of women who stopped breastfeeding dropping out before those who continued.
Propensity score matching is a statistical technique that attempts to
estimate the
effect of a
treatment by accounting for the covariates that predict receiving
treatment.
In addition to prevalence
estimates, the reports also include data on cancer
treatment patterns, survival, and information on common short - and long - term
effects of cancer and its
treatment for eleven selected cancers.
Multilevel logistic regression was used to
estimate the odds ratios (ORs) for conversion to laparotomy, CRM +, intraoperative complications, and postoperative complications between
treatment groups, adjusting for the stratification factors, where operating surgeon was modeled as a random
effect.
James O'Malley, PhD and former post-doc, Jaeun Choi, PhD recently had their paper «
Estimating the causal
effect of
treatment in observational studies with survival time end points and unmeasured confounding» published in The Journal of the Royal Statistics Society; Applied Statistics.
We used random
effects methods to compare dichotomous outcomes (risk ratio for efficacy and odds ratio for safety); therefore
estimates meta - analysed over multiple trials are average
treatment effects.
For
estimating the causal
effect of
treatment exposure on the occurrence of adverse events, inverse probability weights (IPW) can be used in marginal structural models to correct for time - dependent confounding.
All three
effect estimates —
treatment vs. control,
effect of voucher use, and impact of private schooling — are provided in the longer version of this article (see «Summary of the OSP Evaluation» at www.educationnext.org), so that individual readers can view those outcomes that are most relevant to their considerations.
Specifically, he will work with the PI and core project staff to develop an analysis plan, direct the evaluation of the efficacy of the Core Knowledge Language Arts Listening and Learning Read Aloud Program, articulate the fully specified multi-level models used to
estimate treatment impacts on child - level vocabulary, listening comprehension and domain knowledge outcomes, and guide the secondary analyses that examine whether the quality of read alouds mediate
treatment effects on child outcomes and the baseline, child - level moderators of
treatment effects.
I therefore
estimate the
effect of receiving a fail rating by comparing the May test results for schools inspected very early in the same academic year, the
treatment group, with a comparison group of schools inspected after the test is taken in early May but before the results are released in July.
To correct for this, we perform what economists call a «
treatment on the treated» analysis to produce
estimates of the
effects that a trusted organization such as the College Board or ACT would achieve were it to conduct the intervention.
That has the advantage of ensuring that there is no bias in our
estimate of
treatment effects because all groups retain the
treatment status they were awarded by the lottery regardless of whether their performance was cancelled for snow.
Those observations do not contribute directly to the
estimate of the
treatment effect because there is no variance on the
treatment variable within their matched grouping.
Leaving them within the analysis, however, does improve the precision of
estimates for other covariates, which results in a more precise
estimate of the
treatment effect.
In a large randomized experiment such as this, we can
estimate the
effect of receiving the intervention by simply comparing the average outcomes of the
treatment and control groups.
Our use of annual gain scores provides an
estimate of
treatment effects based on the extent to which students at each school do better or worse than would be expected, given their initial test scores.
We therefore see our lottery
estimates as indicative of what the No Excuses charter model can accomplish, rather than an overall charter - school
treatment effect.
It's noteworthy, however, that the observational
estimates of pilot high school
treatment effects are larger for schools used in the lottery study than for other pilot schools.
Estimates of policy
effects are based on comparisons between control and
treatment groups.
Subtracting these two — taking the difference of the two differences between the
treatment and comparison groups — yields a credible
estimate of the policy
effect.
As Figure 1 shows, the
treatment effects were
estimated to be approximately 0.09 in mathematics and 0.07 in reading.
A series of hierarchical linear models will be
estimated to investigate the
effect of
treatment on student learning outcomes.
«We
estimated positive
treatment effects of approximately 0.09 in mathematics and 0.07 in reading, as shown in....
-- Incorporation of more aerosol species and improved
treatment of aerosol - cloud interactions allow a best
estimate of the cloud albedo
effect.
I linked to the paper because it shows a
treatment of the
effect of unforced natural variability upon
estimates of ECS and TCR.
PANSS negative Cognitive therapy did not have a significant
effect on negative symptoms at any follow - up time:
estimated improvement − 1.02 (95 % CI − 2.35 to 0.30) compared with the
treatment as usual group.
Therefore, the PDI score was included in the LME model to reduce the bias of differential attrition on the
estimated treatment effect.
For example, a report by King et al describes correlations between parents» perceptions of services that they receive for their child with a neurodevelopmental disability and their increased satisfaction with services and decreased stress in dealing with their child's
treatment programme.1 Thus, it is likely that evidence reported here is a conservative
estimate of the real
effect that services and programmes can have on the populations of interest.
Using common comparator as usual care would allow to indirectly compare home - based psychological intervention with home - based exercise intervention.43
Treatment effects for each study were
estimated using a two - stage network meta - analysis.
Main
effect of
treatment and
treatment by recruitment source interaction on
estimated mean change in self - rated depressive symptoms (PHQ - 9) from baseline to post and follow - up and minimally clinically relevant change of PHQ - 9 at post-assessment.
Probabilities ± standard errors that correspond to
estimates for dichotomous outcomes presented in Tables 3 and 4 where there were significant
effects or trends for any
treatment contrast.
We
estimated models by using dependent variables previously associated with significant
treatment effects in the follow - up study.10, 20 These included life - course outcomes for the mother, such as number of subsequent children, months on welfare, impairments due to substance use, and number of arrests, as well as life - course outcomes for the study children, such as number of runaway episodes and number of arrests or convictions.
All
estimates of
treatment main
effects and
effects for the unmarried, low - SES group are derived from a common statistical model.
In addition, for 2 variables, the core log - linear model produced unstable variance
estimates for the tests of
treatment main
effects.
Building on these ideas, we used rich data on selection into and out of neighborhoods to formulate a cross-classified multilevel model designed to
estimate causal
effects when contextual
treatments, outcomes, and confounders all potentially vary over time (32, 33, 48).
Analyses used a proportional odds model that
estimated the
treatment effect as the OR of a patient being in a category of more frequent self - harm).
We will draw funnel plots (
estimated differences in
treatment effects against their SE) if we identify 10 or more studies that provide data on an outcome.
Intention - to - treat analyses provide a conservative
estimate of
treatment effects.
Generalized
estimating equations (GEE) models showed small, but significant positive
treatment effects on parental self - efficacy, and marginally significant
effects on social support, and knowledge on child rearing.
For each outcome variable, we
estimated mixed
effects regression models with outcome = a0 (intercept) + a1 (informant) + a2 (
treatment group) + a3 (time) + a4 (condition × time) with intercept, informant, and time (log day) treated as random
effects.
Network meta - analysis combines direct and indirect evidence for all relative
treatment effects (for the selected outcomes) and provides
estimates with maximum power.
Note however that the
effect size (parameter
estimates interpretable as r) was small for both
effects and that no interaction
effects were found to be significant, indicating that child psychopathology measured at pre-assessment was not related to
treatment effectiveness.
Cohen's d
effect size
estimates -LRB-[pre-
treatment — post -
treatment / follow - up] / pooled SD) were provided for all
treatment and follow - up analyses.
These findings provide strong empirical evidence that inadequate allocation concealment contributes to bias in
estimating treatment effects.
A number of methodological studies provide empirical evidence to support these precautions.152 153 Trials in which the allocation sequence had been inadequately or unclearly concealed yielded larger
estimates of
treatment effects than did trials in which authors reported adequate allocation concealment.
Effect size
estimates for all outcome variables suggested large to medium
treatment effects.