In sparse data meta-analyses (with few trials or zero events), conventional methods may distort results. Although better-performing one-stage methods have become available in recent years, their implementation remains limited in practice. This study examines the impact of using conventional methods compared to one-stage models by re-analysing…

Clinical prediction models are widely used in modern clinical practice. Such models are often developed using individual patient data (IPD) from a single study, but often there are IPD available from multiple studies. This allows using meta-analytical methods for developing prediction models, increasing power and precision. Different studies,…

Meta-analysis is a statistical method that combines quantitative findings from previous studies. It has been increasingly used to obtain more credible results in a wide range of scientific fields. Combining the results of relevant studies allows researchers to leverage study similarities while modeling potential sources of between-study…

For meta-analysis of studies that report outcomes as binomial proportions, the most popular measure of effect is the odds ratio (OR), usually analyzed as log(OR). Many meta-analyses use the risk ratio (RR) and its logarithm because of its simpler interpretation. Although log(OR) and log(RR) are both unbounded, use of log(RR) must ensure that…

Standard models for network meta-analysis simultaneously estimate multiple relative treatment effects. In practice, after estimation, these multiple estimates usually pass through a formal or informal selection procedure, eg, when researchers draw conclusions about the effects of the best performing treatment in the network. In this paper, we…

Publication bias distorts the available empirical evidence and misinforms policymaking. Evidence of publication bias is mounting in virtually all fields of empirical research. This paper proposes the endogenous kink (EK) meta-regression model as a novel method of publication bias correction. The EK method fits a piecewise linear meta-regression of…

Background: Stratified medicine seeks to identify patients most likely to respond to treatment. Individual participant data (IPD) network meta-analysis (NMA) models have greater power than individual trials to identify treatment-covariate interactions (TCIs). Treatment-covariate interactions contain "within" and "across" trial…

Numerous ways to meta-analyze single-case data have been proposed in the literature, however, consensus on the most appropriate method has not been reached. One method that has been proposed involves multilevel modeling. This study used Monte Carlo methods to examine the appropriateness of Van den Noortgate and Onghena's (2008) raw data multilevel…

Research synthesis of evaluation findings is a multistep process. An investigator identifies a research question, acquires the relevant literature, codes findings from that literature, and analyzes the coded data to estimate the average treatment effect and its distribution in a population of interest. The process of estimating the average…

The results of a meta-analysis that found that rewards do not threaten intrinsic motivation have not been well accepted by those who argue rewards produce negative effects under a wide range of conditions. Nevertheless, the results and conclusions of the meta-analysis are held to be valid. (SLD)

This paper focuses on transition programs for youth to postsecondary education, broadly considered. It addresses the following questions: (1) What models or programs of transition exist? (2) On what basis can we say one transition program is more effective than another? In other words, how is successful transition defined? (3) How are…

Argues that generalizing to message populations by treating messages as a random variable is inappropriate for complex messages, and proposes meta-analytic techniques for investigating biases in message samples and other methodological factors that can limit generalizability of communication research. (MS)

The conclusion of J. Cameron and W. D. Pierce that rewards do not pose a threat to intrinsic motivation (1994) is a misrepresentation of the literature based on a flawed meta-analysis. Their analysis is more an attempt to defend behaviorist turf rather than meaningful consideration of relevant data and issues. (Author/SLD)

College student employment has been increasing steadily for at least four decades. At present, approximately 80% of all college students are employed while completing their undergraduate education. Even among students under the age of 24 at 4-year colleges, more than 50% are employed during the school year. Although some general trends are…

Given that theory is a crucial component of path analysis and that major theories in the social sciences either directly or by inference assume interaction, it appears that interaction has to be considered in path analytic models that reflect those theories. The use of interaction within the framework of path analytic methodology is investigated…