Research in the domain of video game violence continues to be contentious and debated. Scholars have examined both positive and negative effects of violent games, although results thus far have been inconclusive and systematic internal validity problems have been identified with past research. The current study adds to this growing literature by examining the effects of video game violence expo...

Metalloenzymes often require elaborate metallocenter assembly systems to create functional active sites. The medicallyimportant, dinuclear nickel enzyme urease provides an excellent model for studying metallocenter assembly. Nickel is inserted into the urease active site in a GTP-dependent process with the assistance of UreD/UreH, UreE, UreF, and UreG. These accessory proteins orchestrate apopr...

We describe when and how to use simulation methods in theory development. We develop a roadmap that describes theory development using simulation and position simulation in the “sweet spot” between theory-creating methods, such as multiple case inductive studies and formal modeling, and theory-testing methods. Simulation strengths include internal validity and facility with longitudinal, nonlin...

The PEDro scale was developed to rate the methodological quality trials on PEDro, the Physiotherapy Evidence Database and includes 10 criteria. Ratings of trials in OTseeker, however, are presented separately with respect to items relevant to a trial’s internal validity (8 items) and items relevant to a trial’s statistical reporting (2 items). This is called the PEDro scale (partitioned). A cop...

This study investigated the psychometric properties of the Japanese version of the WHOQOL-BREF among 10,693 community-based married Japanese men and women (4376 couples) who were either expecting or raising a child. Analyses of item-response distributions, internal consistency, criterion validity, and discriminant validity indicated that the scale had acceptable reliability and performed well i...

A common challenge of scientific research is an inability to randomly assign subjects to a treatment that varies on only one variable (e.g., assignment of subjects to groups that differ only in a drug provided). The inability to randomly assign variation on a single treatment variable limits the strength of causal inferences made from the data—a common goal of scientific analysis. Greg Pavela, ...

The randomized controlled trial has emerged as the gold standard for all clinical research. The combination of randomized assignment to groups, use of strict inclusion and exclusion criteria, standardized protocols and ad hoc power analysis serve to rule out many threats to the internal validity of research results. Thus, it is the most powerful methodology available to researchers investigatin...

Restoration psychology has used virtual environments as a research tool in laboratory experiments for a long time; mostly as standins for physical environments, thus making research settings more controllable and enhancing internal validity. Just recently researchers focused on the virtual environments itself, its’ restorative quality and its’ ecological validity (e.g. Kort de, Meijnders, Spons...

The Youth Psychopathic Traits Inventory-Short Version (YPI-S; van Baardewijk et al., 2010) is a self-report measure to assess psychopathic-like traits in adolescents. The aim of the present study is to investigate the factor structure, the internal consistency, and the criterion validity of the YPI-S in 768 Belgian community adolescents (45.4 % males). In general, our study supported the YPI th...

BACKGROUND The quality of the parent-child relationship has an important effect on a wide range of child outcomes. The evaluation of interventions to promote healthy parenting and family relationships is dependent on outcome measures which can quantify the quality of parent-child relationships. Between the Mothers' Object Relations - Short Form (MORS-SF) scale for babies and the Child-parent Re...