Quasi-experimental study designs series – Paper 4: uses and value

• Published in: Journal of clinical epidemiology 2017-09, Vol.89, p.21-29
• Main Authors: Bärnighausen, Till, Tugwell, Peter, Røttingen, John-Arne, Shemilt, Ian, Rockers, Peter, Geldsetzer, Pascal, Lavis, John, Grimshaw, Jeremy, Daniels, Karen, Brown, Annette, Bor, Jacob, Tanner, Jeffery, Rashidian, Arash, Barreto, Mauricio, Vollmer, Sebastian, Atun, Rifat
• Format: Article
• Language: English
• Subjects: Acquired immune deficiency syndrome; AIDS; Bias; Causality; Collaboration; Epidemiology; Experiments; Health care policy; HIV; Human immunodeficiency virus; Humans; Internal Medicine; Intervention; Non-Randomized Controlled Trials as Topic; Quasi-experimental methods; Reproducibility of Results; Research Design; Studies; Validity
• ISSN: 0895-4356; 1878-5921
• DOI: 10.1016/j.jclinepi.2017.03.012

Abstract Quasi-experimental studies are increasingly used to establish causal relationships in epidemiology and health systems research. Quasi-experimental studies offer important opportunities to increase and improve evidence on causal effects: (i) they can generate causal evidence when randomized controlled trials are impossible; (ii) they typically generate causal evidence with a high degree of external validity; (iii) they avoid the threats to internal validity that arise when participants in non-blinded experiments change their behavior in response to the experimental assignment to either intervention or control arm (such as compensatory rivalry or resentful demoralization); (iv) they are often well-suited to generate causal evidence on long-term health outcomes of an intervention, as well as non-health outcomes such as economic and social consequences; and (v) they can often generate evidence faster and at lower cost than experiments and other intervention studies.