External and Internal Validity of a Geographic Quasi-Experiment Embedded in a Cluster-Randomized Experiment

Background: Randomized experiments yield unbiased estimates of treatment effect, but such experiments are not always feasible. So researchers have searched for conditions under which randomized and nonrandomized experiments can yield the same answer. This search requires well-justified and informative correspondence criteria, that is, criteria by which we can judge if the results from an appropriately adjusted nonrandomized experiment well-approximate results from randomized experiments. Past criteria have relied exclusively on frequentist statistics, using criteria such as whether results agree in sign or statistical significance or whether results differ significantly from each other. Objectives: In this article, we show how Bayesian correspondence criteria offer more varied, nuanced, and informative answers than those from frequentist approaches. Research design: We describe the conceptual bases of Bayesian correspondence criteria and then illustrate many possibilities using an example that compares results from a randomized experiment to results from a parallel nonequivalent comparison group experiment in which participants could choose their condition. Results: Results suggest that, in this case, the quasi-experiment reasonably approximated the randomized experiment. Conclusions: We conclude with a discussion of the advantages (computation of relevant quantities, interpretation, and estimation of quantities of interest for policy), disadvantages, and limitations of Bayesian correspondence criteria. We believe that in most circumstances, the advantages of Bayesian approaches far outweigh the disadvantages.

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Interventions Adopting Body-Mind-Spirit Model to Improve the Holistic Health of Older Adults: A Systematic Review

Innovation in Aging ◽

10.1093/geroni/igab046.3404 ◽

2021 ◽

Vol 5 (Supplement_1) ◽

pp. 951-951

Author(s):

Xinyue Hu ◽

Tongtong Li ◽

Iris Chi

Keyword(s):

Systematic Review ◽

Older Adults ◽

Empirical Studies ◽

Internal Validity ◽

Cluster Randomized Trial ◽

Holistic Health ◽

Medium Quality ◽

Cluster Randomized ◽

Definition Of ◽

Randomization Process

Abstract This systematic review aims to summarize 5 key information from non-pharmaceutical intervention studies which adopt Body-Mind-Spirit (BMS) model for older adults: (1) definition of BMS, (2) types and formats of the interventions, (3) background and BMS training of the interventionists, (4) activities included in the interventions, and (5) effect of these interventions on the holistic health of older adults. We conducted a systematic search of 9 databases (ProQuest, Web of Science, PsycINFO, PubMed, Cochrane, Wanfang, AIRITI, CADAL, CNKI) for studies published in English or Chinese through May 31, 2021. Inclusion criteria were: (1) Must be empirical studies; (2) Participants must be aged 55 and above; and (3) Must adopt the BMS model or contain BMS in full-text. We found 15 studies (7 RCTs, 1 cluster randomized trial, 3 mixed-method studies, and 4 qualitative studies). Ten studies (66.67%) adopted Chan’s BMS model. Thirteen studies (86.67%) adopted in-person group interventions. Only five studies (33.33%) provided BMS training to the interventionists. Six articles (40%) categorized the activities as body-, mind- or spirituality-related. Ten studies (66.67%) reported effectiveness in all 3 dimensions of BMS. Of the 7 RCTs, 5 were rated as medium-quality, and 2 were rated as low-quality according to the Cochrane’s Risk of Bias tool. Most interventions based on the BMS model claimed to be effective in improving the holistic health of older adults. In order to improve the internal validity, future RCT studies should be more prudent about the randomization process and adhere to the BMS model when designing the interventions.

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The Effectiveness of Social Therapy in Prison—A Randomized Experiment

Crime & Delinquency ◽

10.1177/0011128700046002005 ◽

2000 ◽

Vol 46 (2) ◽

pp. 214-232 ◽

Cited By ~ 23

Author(s):

Rüdiger Ortmann

Keyword(s):

Longitudinal Design ◽

Internal Validity ◽

Effect Sizes ◽

Randomized Experiment ◽

Correctional Treatment ◽

Social Therapy ◽

High Internal Validity ◽

The Way

Studies on the effectiveness of correctional treatment in prison often strive for a high internal validity but neglect aspects of substantiation of content. This study tries to reach high internal validity and to treat the question of how much effectiveness can be expected in prison at all. Therefore, the way from treatment to recidivism is examined for important groups of variables with a longitudinal design. The results show that the success is rather low and prison is an extremely unfavorable place for a positive correction of people. The benefit of correctional treatment in prison for society is apparently overrated if studies only take into account the potentially positive—the effect sizes after correctional treatment—and exclude the negative aspects.

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