Overview
The following paper provides a critique of the study on “Long-term retention of older adults in the cardiovascular health study: Implications for studies of the oldest old.” The paper utilizes epidemiology and biostatistics concepts to analyse the study. Some of the important concepts discussed include identification of the research problem, research questions, generation of hypothesis, research design used and its validity to the study, justification of research methods, and suitability of data analysis procedure. Epidemiology and biostatistics concept provides an individual with skills to design and implement fundamental and practical research healthcare (Texas A&M Health Science Centre, 2014).
In which paragraph(s) of the study is a research problem stated?
The research problem statement for this study is found in the first and second paragraph in the introduction section. The information provided in these two paragraphs relate to the research topic. In paragraph one, researchers claim that adults aged 80 and older have high-risk factors and health outcomes, hence, best for cardiovascular health studies. Researchers introduce a problem of lack of records showing the retention rates of older adults in cardiovascular health study. In the second paragraph, the study talks about the importance of repeated in-person visits in relation to older population and retention rates (Stotmeyer, Arnold, Boudreau, Ives, Cushman, Robbins, Harris, & Newmann, 2010). The study however
The significance of statement of purpose
A statement of purpose clarifies to the reader the main lessons that a researcher would learn from conducting the study. The study presented a statement of purpose in the third paragraph, but it was not effectively done. An effective statement of purpose should set the objectives and the intention of conducting a study. In addition, it should incorporate qualitative inquiry by using such words as intent, purpose, or objective (Wood & Kerr, 2011, pp. 80-81). Where can a reader find such words as purpose, intention, or objective in this study? It shows well that the study failed to present a statement of purpose according to epidemiology and biostatistics concepts.
The research question (s)
The study somehow specified the research question but not in an acceptable manner. According to Wood & Haber (2010, p. 34), a fully developed research question should identify the variables under consideration, imply the possibility of empirical testing and specify the target population. The study makes it hard for the reader to identify research questions because they are not specified. A reader must struggle reading the paper because it lacks the basic sub-titles that represent various sections of an epidemiological research.
The hypotheses
The study reported a directional hypothesis. A directional hypothesis gives a more specific explanation of the expectations of research outcomes through predicting the relationship that will exist between variables, and further gives the direction of the relationship. In the study, the hypotheses provided a relationship between visits and participants lifestyle, demographics, health, and functionality. In addition, it provides a direction by proposing that that the oldest participants would likely achieve the poorest retention for in-person visits (Sullivan, 2008). The study reported a simple hypothesis because there was no mention of either null hypothesis or alternative hypotheses. The study tested the hypothesis using significance levels equal to 0.01 and 0.05. In addition, test statistics and sampling distribution took place from the data collected. Researchers failed to assess the probabilities associated with the test statistics because the study lacked null and alternative hypotheses.
Intervention
The study provided an intervention at in the last paragraph where authors expressed their gratitude to all those who made the study possible. The intervention, however did not meet the threshold as provided in the epidemiology and biostatistics concept analysis processes. The study failed to incorporate other stakeholders like the government and the health care institutions that would provide valid information concerning the target population. In addition, the study did not have a budget to make future researchers identify gaps in such critical areas financing.
The following study falls under the longitudinal category of research. The researchers followed the participants’ behaviours over a long period, from 1999 to 2005/2006 while performing continuous monitoring of risk factors associated with retention of older people. In addition, a large population of five thousand, eight hundred and eighty participants took place in the study.
Appropriateness of the research design to goals and levels of evidence
The study aimed at describing retention according to age and visit type (home, clinic, telephone), and investigates characteristics associated with visit types for longitudinal epidemiological study in older adults. A longitudinal cohort study design was used to achieve the research goals. The longitudinal cohort design was appropriate for the study because it involves repeated observations of variables over a long period. This type of design has a disadvantage in that it has less power in detecting underlying relationships. An experimental design would have been more appropriate for this study. An experimental design helps in establishing the validity of a hypothesis through manipulating particular factors. From the longitudinal cohort design used, the study achieved a 22.3 percent increase (from 36.5 to 58.8 percent) in in-person retention (Stotmeyer, Arnold, Boudreau, Ives, Cushman, Robbins, Harris, & Newmann, 2010). An experimental design introduces the treatment and procedure that assist in developing the outcome of the study. In addition, the design utilizes a large number of participants who make statistical results valid and reliable (Cottrell, & McKenzie, 2011, p. 191). The study by Stotmeyer, Arnold, et al. did not have a specific outcome because the longitudinal cohort design could not specify the expected percentage increase in in-person retention.
Application of power analysis procedure to the study
Power analysis plays a role when a researcher plans using inferential statistics. It helps determining sample size of the study for effective evaluation of results. The study never used power analysis because there was no inferential statistics test signifying the null and alternative hypotheses. It was not established how the study came up with a big sample size without conducting an inferential statistics to determine the suitability of sample size to the research outcomes. The absence of power analysis had some implications. Researchers could not identify the power of the study. The study lacked sensitivity because researcher worked blindly towards an unknown destination. The study assumed a larger effect on the research topic but forgot that power analysis helps in missing meaningful effects that would help improve results. Moreover, researchers assumed the number of observations for their target group. Power analysis helps in determining the exact number of observations required and makes researchers make informed decisions that have positive effects on research goals (Murphy, & Myors, 2014).
The relationship between research methods and findings, does the study methods justify the population sample used?
The study methods explained in four sections: study participants; Visit types; demographics, health and functional characteristics; and statistical analysis. Participants underwent thorough baseline evaluations to ensure they were fit for the study. The process took place in stages between year 1999 and year 2005/06. In addition, questionnaires helped in determining participants’ demographics and lifestyle characteristics. Validity and reliability of the research methodology justify its appropriateness in achieving the research objectives. The research would have used a stratified sampling technique that allows researchers to breakdown samples into various categories depending on demographics, lifestyle, and health status. The methods used failed to justify the interference because no pre-study was conducted to determine the validity and reliability of research methods.
Discuss the degree to which statistical tests of analysis support the research variables and design
Any statistical test used by the researcher should support the research variables and design in order to achieve desirable results (Burns, Grove, & Gray, 2011). The study utilized the analysis of variance (ANOVA) and Chi-square tests. These two tests helped in determining the relationship between test variable, but they were not the most appropriate for this study. The study would have use a multivariate ANOVA (MANOVA) test and contingency tables. MANOVA would be more effective in analysing risk factors associated with a continuous variable while contingency tables help in relating the dependence of variables tested and risk factors (for example, the relationship between age and in-person retention). In addition, other types of data testing such as the T-test would be more appropriate for this study. How could the study include a hypothesis without utilizing a t-test? A t-test forms the best statistical tool for testing the hypothesis of the research. The tests somehow estimated the probability that results obtained from the sample represented the true population. The results indicated that home, telephone, and proxy visits improved the in-person retention by more than 20 percent in a period of ten years.
Were the study outcomes valid and reliable?
A look at the research objectives helps in determining the validity and reliability of study outcomes. The objectives of the study were to describe the retention according to visit types and age, and determine characteristics associated with visit types for longitudinal epidemiological study in older adults (65 and above years). The outcomes of the study showed that use of home, telephone and proxy visits help optimizing follow-up of aging people. Theoretically, the three visit types have a significant effect on in-person retention. According to Booker, Harding, & Benzeval (2011), face-to-face interviews alone increased retention rates by 24 percent in a study to review the effects of retention methods in population-based cohort studies. The following study outcome showed a 22.3 increase, a slightly lower value but within the range of 20 to 30 percent.
Are the outcomes clinically relevance?
The study outcomes for the study showed some clinical relevance because the research was among many conducted in the same topic. The medicine and nursing sector needs more knowledgeable and advanced practitioners capable of improving the quality of life and well-being of people in the society. The outcomes of this study play significant roles to the clinical practice by making practitioners more aware of advantages of different visit types in long-term retention of older adults.
Impact of the literature review to the study
Researchers provided a non-comprehensive literature review. The information provided in one paragraph was not sufficient in making readers understand the research gaps. In addition, the literature review lacked major sectors such as findings from previous studies, challenges faced during previous studies and how the current study plans to mitigate them, and the new approaches to the research topic. The study did not specify the main problems that the reader should think about while going through the literature. Moreover, the literature had less significance to the study because it never pointed out other similar studies conducted by researchers before and their findings. The study would have been more specific if it concentrated on literature on long-term retention on younger people and their relationship with the older population.
Discuss the levels of evidence
The study shows two levels of evidence, level I and level III. In level I, a study demonstrated a high randomised investigation study that tests a previously developed diagnostic criterion. The study tested a phenomena previously investigated by many researchers, but developed unique findings that have never been found before. In addition, the study was more sensitive to the variables used such as age, sex, demographics, and physical environment. Level III represents a therapeutic study where non-consecutive patients are investigated. The study findings revealed poor estimates on the issue of age because even younger patients would have shown similar results.
Discuss how this study could be implemented in your own clinical practice or impact your clinical interventions in general
The following study would be more relevant to the clinical practice if the researchers concentrated more on a small population. Clinical studies involving thousands of participants provide misleading results because the researcher fails to account for a large number of responses gathered from many participants. On the other hand, the study should have used a pilot study. The authors would have conducted a pilot study with a small target population to determine the validity of research design used during the main study. In addition, the pilot study would have assisted in determining expected challenges during the actual implementation of the project.
The interventions provided on this research have a lot of influence to the field of nursing. The interventions calls upon researchers to implement effective research designs capable of achieving expected clinical results in a more convenient manner. The authors who conducted this research did not take into consideration the impact of the longitudinal cohort design in conducting clinical studies. Studies in the medicine and clinical field are very sensitive and researchers should focus on gathering true information that represents the real situation on the ground. Experimental designs form the most recommended method of conducting studies in the clinical practice.
Identify areas that pose threats to validity and reliability of the findings
The sampling criteria used in the study raised questions on the validity of the results obtained. The study would have just used a small sample group to represent a bigger population in order to avoid type II errors associated with the large number of participants. Begi (2009) argued that the most appropriate sample size is the one forming more than 10 percent of the total population. Table 1 shows results of various sample sizes used for three visit types with a total of 2,281 participants in year 1998/1999 {(2281/43772)*100 = 5.2%}. This sample group formed less than 10 percent of the total population that questioned the suitability of the sampling criteria used.
Control of threats to reliability and validity
Concerning the sample size used by researchers, the study ensured validity of the information collected by dividing the data collection process into stages. The information gathered during the first stage of 5 years was used in determining consistency during the following 5-years stage. On the other hand, the reliability of the data was mitigated through repeated observations on one target group for a long period. For instance, researchers would concentrate more on one particular type of visit for a period of more than six months to determine the truth of the information.
References
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