Related Experiment Video
Updated: May 1, 2026

Treatment Model for Young Patients with Psychogenic Erectile Dysfunction and Resultant Infertility
Published on: May 30, 2025
How to assess the external validity and model validity of therapeutic trials: a conceptual approach to systematic
Raheleh Khorsan1, Cindy Crawford2
1Military Medical Research, Samueli Institute, 2101 East Coast Highway, Suite 300, Corona Del Mar, CA 92625, USA ; Department of Planning, Policy, and Design, School of Social Ecology, University of California Irvine, Irvine, CA 92697-7075, USA.
Abstract:
Background. Evidence rankings do not consider equally internal (IV), external (EV), and model validity (MV) for clinical studies including complementary and alternative medicine/integrative medicine (CAM/IM) research. This paper describe this model and offers an EV assessment tool (EVAT©) for weighing studies according to EV and MV in addition to IV. Methods. An abbreviated systematic review methodology was employed to search, assemble, and evaluate the literature that has been published on EV/MV criteria. Standard databases were searched for keywords relating to EV, MV, and bias-scoring from inception to Jan 2013. Tools identified and concepts described were pooled to assemble a robust tool for evaluating these quality criteria. Results. This study assembled a streamlined, objective tool to incorporate for the evaluation of quality of EV/MV research that is more sensitive to CAM/IM research. Conclusion. Improved reporting on EV can help produce and provide information that will help guide policy makers, public health researchers, and other scientists in their selection, development, and improvement in their research-tested intervention. Overall, clinical studies with high EV have the potential to provide the most useful information about "real-world" consequences of health interventions. It is hoped that this novel tool which considers IV, EV, and MV on equal footing will better guide clinical decision making.
Related Concept Videos
Types of Biopharmaceutical Studies: Controlled and Non-Controlled Approaches
Non-controlled studies, commonly employed for initial exploration, lack a control group, rendering them susceptible to biases and external influences. In contrast,...
Data Validation
Nursing assessment guides are generally based on holistic models rather than medical...
Clinical Trials
There are four phases in a clinical trial. A phase one...
Elements Crucial for Effective Psychotherapy
The Therapeutic Alliance
The therapeutic alliance refers to the relationship between the therapist and the client. The alliance strengthens when the therapist and the client engage in a nurturing, supportive, trusting, empathetic, and respectful relationship, improving therapeutic outcomes. Therapists must monitor this relationship...
Modeling in Therapy
Participant Modeling
Participant modeling involves therapists demonstrating calm and effective behaviors in...
Reliability and Validity
