Introduction
The reliability of the evidence and conclusions of the research depends on the methodology chosen and applied by the authors. The analysis presented in the current paper is part of an integrative review devoted to studying the impact of exercise intervention on the cognitive performance of older patients with dementia or cognitive impairment. The report considers the methodology of the articles examined, namely their research methods, approaches for data collection and analysis, inconsistencies, and gaps.
Research Methods
The choice of publications for the review was based on strict exclusion criteria; therefore, the methodology maintains a high level of evidence. All included studies are randomized controlled trials (RCT), which follow a quantitative design and correspond to the II level of evidence. Although some elements differ, all research problems in the papers analyzed follow a similar scheme and focus on the impact of exercise-related interventions and several additional interventions on various aspects of cognitive performance. RCT is a suitable format for such a study, as it helps establish causal relationships, increases validity, and reduces bias and the impact of confounding factors through randomizing participants.
The researchers chose different approaches when selecting participants and the duration of the studies, which also affected quality. The time of the studies differed from six months for Gaitán et al. (2021), Mendez Colmenares et al. (2021), Morris et al. (2017), a year for Tarumi et al. (2022), 18 months for Lenzeet al. (2022), and two years for Sink et al. (2015). RCTs include different participants: Gaitán et al. (2021) have the smallest sample, 23 persons, and Sink et al. (2015) have the most significant number, 1,635 participants.
The study’s duration and number of participants make Sink et al. (2015) the most substantial research. Therefore, a key recommendation for research methodology is to increase the length of observations to understand long-term effects and involve more participants. Nevertheless, examining the presented articles provides valuable and trustworthy information thanks to reliable methodology.
Data Collection and Statistical Data Analysis
The studies included in the review use many data collection and analysis methods. Research by Gaitán et al. (2021) stands out as the focus is on biomarkers related to learning and memory, which required a blood test to collect information. All studies used neuropsychological or cognitive test batteries to measure participants’ cognitive performance levels, and several also included cardiorespiratory fitness assessments.
Moreover, most studies used MRI except for Gaitán et al. (2021) and Sink et al. (2015). The benefit of the selected data collection methods is a focus on the cognitive abilities of participants, which makes it possible to assess the effect of exercise on them. However, all studies use many evaluations, which could overload participants physically and mentally and affect the accuracy of the results.
Most studies reviewed used statistical methods such as mixed-effects models and regression analyses to analyze the data. They are suitable for considering the influence of one variable on another and, therefore, correspond to the problems posed and the chosen methodology, which are the studies’ strengths. However, only Lenze et al. (2022) and Tarumi et al. (2022) mention that confounding factors were considered during the investigation. Lack of attention to this problem can lead to distortion of results. Overall, the authors used a suitable and practical approach to data collection and analysis, but improvements are possible through reducing the stress of assessments on participants.
Gaps and Inconsistencies
Despite the robust methodology and rigorous research process, one may highlight gaps and inconsistencies. For example, all selected studies were conducted in the US, but only two studies drew attention to the ethnicity of participants: Lenzeet al. (2022) and Sink et al. (2015). Given the diversity of the country’s population, this factor should be considered and discussed in research for better generalization of results.
Moreover, all authors of the selected studies mention the importance of the outcomes in understanding and treating dementia. However, only Morris et al. (2017) included participants with early-stage Alzheimer’s, while Gaitán et al. (2021), Lenze et al. (2022), and Sink et al. (2015) enrolled people with mild concerns or risks. Engaging participants with dementia may be difficult, but it is necessary to understand the condition and possibilities of interventions.
Research has also focused on several narrow areas of cognitive functioning. This feature is both an advantage and a limitation in the examined articles. On the one hand, a detailed study of each function is essential for the accuracy of the results. On the other hand, the authors may have missed the broader prospect of the influence of the chosen intervention. The gaps and inconsistencies presented can be explained by the fact that conducting studies requires significant resources and a balance between the desired methodology and the authors’ capabilities. As a result, studies may not fully meet the researchers’ desirable standards but still have practical value.
Conclusion
Thus, the current report explores research methods, data collection, and analysis approaches. The studies included in the review are SCT and used robust processes, contributing to the reliability of the findings. Moreover, the authors of the publications used many techniques to collect and analyze information. They were consistent with the chosen approach to the study and maintained the trustworthiness of the evidence. Despite the careful strategy for choosing methods, gaps and inconsistencies exist, for example, when recruiting participants. Most studies would improve if they increased the number of people involved and the duration of observations.
References
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