Randomized controlled trials (RCTs) are routinely used in medicine and are becoming more popular in economics. Data from RCTs are used to learn about treatment effects of interest. This paper studies what one can learn about the average treatment response (ATR) and average treatment effect (ATE) from RCT data under various assumptions and compares that to using observational data. We find that ...

Validity is an enduring theme in the information systems (IS) domain. However, because much of that discussion draws, at least nominally, on an Empiricist orientation, formulating issues of validity in a way that is pertinent to a practice-oriented discipline has been difficult. This is particularly true for external validity, which refers to the applicability, or relevance, of research to phen...

Pintrich & De Groot, 1990). Motivational components include students' perceptions of the classroom environment as well as their self-related beliefs such as personal goals, self-efficacy, interest, and value beliefs. Cognitive components include students' content knowledge as well as various cognitive learning strategies such as rehearsal, elaboration, and organization, and metacognitive strate...

1. Background In the UK, the NIHR vision sees ‘more patients and health professionals participating in health research’ [1]. Fundamental to health research is the testing of interventions through RCTs. Achieving high participation in RCTs has traditionally been difficult. Published data show that a minority of RCTs recruit successfully [2,3]. Recruitment problems reduce the total recruited samp...

Introduction Randomised Controlled Trials (RCTs) produce relative treatment effects that have high internal validity. However they may suffer from lack of external validity when used as inputs to cost-effectiveness analyses (CEA). If differences in RCT and CEA populations can be described by a set of observed covariates, then it is possible to adjust for these differences. A common approach is ...

External validity is a challenge in treatment effect estimation. Even in randomized trials, the experimental sample often differs from the population of interest. If participation decisions are explained by observed variables such differences can be overcome by reweighting. However, participation may depend on unobserved variables. Even in such cases, under a common support assumption there exi...

Winer (1999 [this issue]) proposes that external validity concerns require more attention in theoretical research. The author argues that one cannot “enhance” external validity by choosing one method over another. External validity can only be “assessed” by better understanding how the focal variables in one’s theory interact with moderator variables that are seen as irrelevant early in a resea...

Ethical decision making measures are widely applied as the principal dependent variable used in studies of research integrity. However, evidence bearing on the internal and external validity of these measures is not available. In this study, ethical decision making measures were administered to 102 graduate students in the biological, health, and social sciences, along with measures examining e...

This study is a conceptual replication of Karimi et al.’s (2007) study on the impact of ERP implementations on business process outcomes among US manufacturing firms in a Sub-Saharan African (SSA) nation. The results of the measurement model are valid and reliable, which are consistent and comparable with that of the original study, enhancing the external validity of the constructs proposed in ...

This paper examines the nature and the origins of almost twenty years of controversy between ecological (i.e., real-life) and traditional (i.e., laboratory) approaches to memory research and critically analyses the concept of ecological validity a core issue in this controversy which has received surprisingly little attention. The analysis of ecological validity suggests that it is comprised of...