America's diverse higher education landscape includes more than 700 four-year nonprofit colleges and universities that focus on baccalaureate education. These private nondoctoral (PND) institutions are located in almost every state and collectively enroll about 1.6 million students and award nearly 150,000 degrees annually, with the majority of…

The use of virtual laboratories has become an increasing issue regarding science laboratories due to the increasing cost of hands-on laboratories, and the increase in distance education. Recent studies have looked at the use of virtual tools for laboratory to be used as supplements to the regular hands-on laboratories but many virtual tools have…

This study uses within-study comparisons to assess the relative importance of covariate choice, unreliability in the measurement of these covariates, and whether regression or various forms of propensity score analysis are used to analyze the outcome data. Two of the within-study comparisons are of the four-arm type, and many more are of the…