A summary of the article Lipid metabolism in cognitive decline and dementia shows that the study was a nonrandomized pre-post interventional investigation. This illustrates the nomenclature of quasi-experimental design because the outcomes were based on observations without any interference with external variables being introduced into the study (Panza et al., 2006). The research was conducted by collecting data to establish the causality between the intervention and the outcomes. Using no-randomly selected control groups, the study was done using both pre-intervention and post-intervention measurements (Panza et al., 2006). Here, the article details the effects of cholesterol homeostasis and lipoprotein disturbances as the risk factors that cause a cognitive decline of degenerative vascular dementia and Alzheimer’s disease. The results showed that “there was no consistent association of serum or plasma apo E protein levels with the disease when controlled for APOE genotype” (Panza et al., 2006). The research design factored both natural situations and pre-existing groups of participants in the category of people with the attributes of the quasi-experimental research design (Trochim, 2006). There is evidence to show the existence of cause-and-effect relationships between the administered drug and the level of cholesterol. A population-based study of the effects of cholesterol level on dementia for people aged 70 was followed for 18 years. A strong causality between the variables was established (Trochim, 2006). Some ethical reasons were factored into the research study because of the importance of ethical decisions. This was the reason underpinning the use of the quasi-experimental research design. Typically, the research results of the design were accurate because the natural and the causal relationship between the variables were established.
References
Panza, F., D’Introno, A., Colacicco, A. M., Capurso, C., Pichichero, G., Capurso, S. A., … & Solfrizzi, V. (2006). Lipid metabolism in cognitive decline and dementia. Web.
Trochim, W. (2006). Research methods knowledge base. Experimental research Design. Web.