Sentences with phrase «controlling for selection bias»

The results in Table 10 support the notion that the observational study design does a good job of controlling for selection bias in the evaluation of charter effects (or that there is not much selection bias in the first place).

In contrast, ESSA defines four levels of «evidence - based» practices: «strong,» with at least one well - designed and well - implemented experimental study with a statistically significant, positive effect; «moderate,» with at least one well - designed and well - implemented quasi-experimental study such as a matched - comparison group; «promising,» with at least one well - designed and well - implemented correlational study with statistical controls for selection bias.

Promising — at least one well - designed and well - implemented correlation study with statistical controls for selection bias.

Using an instrumental variables approach to control for selection bias, the results suggest an increase in collegiate class size leads to an increase in dropout rates and a reduction in on - time degree completion, but no change in long - run degree completion.

Not exact matches

The study emphasizes controlling for any self - selection bias associated with the type of investors who seek advice, and focuses on common stock holdings to avoid any conflicts associated with mutual fund incentives.

The strengths of the study include the ability to compare outcomes by the woman's planned place of birth at the start of care in labour, the high participation of midwifery units and trusts in England, the large sample size and statistical power to detect clinically important differences in adverse perinatal outcomes, the minimisation of selection bias through achievement of a high response rate and absence of self selection bias due to non-consent, the ability to compare groups that were similar in terms of identified clinical risk (according to current clinical guidelines) and to further increase the comparability of the groups by conducting an additional analysis restricted to women with no complicating conditions identified at the start of care in labour, and the ability to control for several important potential confounders.

A randomised controlled trial would be the best way to tackle selection bias of mothers who plan a home birth, but a randomised controlled trial in North America is unfeasible given that even in Britain, where home birth has been an incorporated part of the healthcare system for some time, and where cooperation is more feasible, a pilot study failed.31 Prospective cohort studies remain the most comprehensive instruments available.

These studies are at risk for selection bias both of cases and of control individuals and their results might be influenced by potential confounders such as other health behaviors that may be independently associated both with breastfeeding and childhood leukemia risk, although this is of course not limited to case - control studies.

Except for male sex, which was not a risk factor in study participants, the ORs obtained from participants were similar to those obtained from all eligible cases and controls, providing no evidence of a noticeable selection bias.

Researchers explained that this difference may be due, in part, to a selection bias where healthier patients were treated with surgery, and they underscored the need for a controlled clinical trial with matched patients receiving each treatment first - line to compare the efficacy of these therapies.

First and foremost, this was not a randomized controlled trial, and there were inherent selection biases that can be controlled for but never completely eliminated.

After controlling for student and peer attributes and for selection bias, we still find a substantial positive and statistically significant effect of attending a network school on student achievement.

While selection bias is still a concern, it is worthwhile noting that the authors control for a very rich set of covariates including student demographics, parental income, parental education, student AFQT score, freshman year GPA, state of birth and various school characteristics.

Results avoid bias from within - country selection and are robust to continental fixed effects and to controlling for non-performance-based forms of teacher salary adjustments.

In this analysis, I attempt to control for a variety of potential selection biases.

The second innovation is the use of the Hispanic cohort's 10th grade basic math scores as a control for performance - based selection biases among the different language treatments.

Selection bias was accounted for as extensively as possible — given the lack of an appropriate instrumental variable — through the inclusion of a number of control variables that are related to parental involvement and student performance.

The use of these models allows researchers to control for potential selection biases of the Fellowship's rigorous entrance requirements, as well as other potential sources of bias.

Can these self - selection biases ever be completely controlled for?

The study emphasizes controlling for any self - selection bias associated with the type of investors who seek advice, and focuses on common stock holdings to avoid any conflicts associated with mutual fund incentives.

Also, we used objective approaches to quantify neighbourhood attributes that allowed us to partially control for potential reverse causality due to depressed individuals tending to exhibit negative cognitive bias resulting in negative thoughts and perceptions.65 Residential self - selection bias is likely to be a trivial source of reverse causality in this study because Hong Kong's high levels of population density (6760 people / km2) and low percentage of developed land (less than 25 %) 66 limit most residents» choice of accommodation and 37 % of Hong Kong older adults live in public rental housing.67 Given the satisfactory response rate and the level of similarity in depressive symptoms and sociodemographic characteristics of participants recruited from two types of recruitment centres, the findings from this study are likely to be generalisable to the population of Chinese Hong Kong older adults matching the study eligibility criteria and other populations of older adults living in similar ultra-dense metropolises of Southeast Asia.

Although this study has some shortcomings such as small sample size, potential selection bias, and less than ideal controls (eg, treatment group was seen for a longer period than control group), the results are promising and consistent with data from previous studies in non-medical patients with depression.

The quasi-experimental design reduces spillover effects but does not eliminate the possibility of selection bias.41, 42 The use of prospectively identified control subjects was intended to minimize discrepancies in outcomes between the 2 designs.43 For some outcomes, as noted previously, the magnitude and direction of outcomes for intervention and control families at randomization and quasi-experimental sites were comparable, although they were statistically significant only at quasi-experimental sites and in the larger pooled sampFor some outcomes, as noted previously, the magnitude and direction of outcomes for intervention and control families at randomization and quasi-experimental sites were comparable, although they were statistically significant only at quasi-experimental sites and in the larger pooled sampfor intervention and control families at randomization and quasi-experimental sites were comparable, although they were statistically significant only at quasi-experimental sites and in the larger pooled sample.

The quasi-experimental design reduces spillover effects and makes it easier to implement the program, but does not eliminate the possibility of selection bias.35, 36 The use of prospectively defined controls at quasi-experimental sites likely contributed to minimized discrepancies in outcomes between randomization and quasi-experimental groups.37 For several parenting outcomes, such as discipline practices, findings were of similar magnitude and direction at randomization and quasi-experimental sites, but statistically significant at only quasi-experimental sites, where the sample size was larger; they were significant in the pooled sample, as well.

Researchers also estimated the preintervention differences and growth over time while controlling for possible selection bias.

A randomized controlled trial comparing I - PCIT to both a control group and standard PCIT would provide further confidence in these findings and would be important to address a potential self - selection bias for parents choosing an intensive treatment.

However this study was rated as weak in quality with a cross-sectional design, possible selection bias with recruitment relying on response to advert and lack of control for confounders.