Epidemiology and Research Methods Samples †MyAssignmenthelp.com

Question: Discuss about the Epidemiology and Research Methods. Answer: Introduction The researchers have given an elaborate literature review to demonstrate their study motivation. A review of literature in a research study involves a critical summary of the studies that are related to the topic of interest, often developed to conceptualize a research study (Polit, 2016). They have begun by quoting studies to show the relationship between intake of anti-psychotic drugs and weight gain as well as obesity-induced conditions as heart diseases, which is adequate. They have clearly and concisely described about various studies to demonstrate the relationship between Clozapine and its effect on weight and obesity-caused disorders among schizophrenia patients. They have concentrated more on the association of Clozapine intake with cardio-vascular risks, which could be understood that the authors wanted to concentrate more on weight gain that is associated with cardiac disorders. The literatures included were relevant, recent and appropriate with correct in-text citations. Most of the studies are current yet few studies are very old to consider. Though the older studies are highly helpful to understand the underlying concepts as well as the effect of clopiazine in that period, it could increase the chance of bias in understanding the fundamental concepts, as science advances day by day (Tappen, 2010). They have mentioned a couple of studies to show the effect of diet control programs on the clozapine-treated schizophrenic patients, which showed contradictory results. This has motivated the researchers to conduct a randomized- controlled trial to determine the effect of regular physical-activities with dietary-control programs (6-month) on obese, schizophrenic in-patients those treated with clozapine. They have measured anthropometric with bio-chemical indices (triglycerides, cholesterol, serum-glucose, insulin levels, cortisol levels, prolactin levels, growth-hormone as well as IGF-1 IGFBP-3) at 3rd and 6th months. This shows that the researchers have described their views systematically, logically as well as sequentially in an unbiased way (Greenhalgh, 2010). They have demonstrated their insight into the problem by involving more suitable and comprehensive studies. Research Formulation The researchers have identified the study problem appropriately and have given the study statements as per PICOT framework (Population, Exposure/Intervention, Comparison/ Control Outcome). A study problem is defined as a perplexing condition that requires investigation by a disciplined inquiry (THS, 2015). The research text suggests that the researchers are interested in evaluating the effect of weight control program on cloziapine- treated schizophrenic patients; at risk for weight gain of at-least 4.45 kg as well as obesity- related risks. The authors have stated a clear and appropriate research- purpose to evaluate the effect of diet control plus exercise program on the outcomes of obese schizophrenic patients taking clozapine. The purpose of a study should agree with its problem and title (Fink, 2013) which is evident in this study. They have given a clear and an achievable objective as to evaluate the effect of diet control as well as physical activity regimen that is given for six- month period on the obese schizophrenic in-patients under clozapine. Hypothesis is an expected or predicted relationship between two variables (Polit, 2016). The researchers have not clearly stated their hypothesis yet it could be understood from the objectives. Sampling and sample size According to Greenhalgh (2010), the process of selecting the target population and the samples is highly critical in a research study. The target population involves a population group in which the authors are interested in collecting data and generalizing the results (Houser,2011). Their selection of target population of 753 hospitalized schizophrenia patients admitted from 2003 September to 2004 February is appropriate. They have selected the patients who were diagnosed as schizophrenia based on DSM-IV criteria particularly between 18 to 65 years of age. Sample is a subset of the population who are selected to represent the entire population (LoBiondo-Wood, 2014). According to Moule (2013), a sampling plan involves selecting samples appropriately with sampling technique. They have selected 56 samples based on inclusion and exclusion criteria. They have randomly assigned 25 samples to control group and 28 samples to study (interventional) group (with 3 samples withdrawn from control group as they have discharged) which is adequate for a RCT trial. Yet, power analysis was not done to select an appropriate sample size. As given by Polit (2016), random sampling is a technique by which samples are selected in such a way of providing equal opportunity to all the members of target population being studied which could reduce bias and hence is highly appropriate. The researcher has given intervention of dietary control with physical activity regimen continuously for six- months to study group while no intervention to control group. Research design Research design is an overall plan that is framed to address the study hypothesis (Polit, 2016). In this study, the researcher has selected the most appropriate randomized controlled trial (RCT) design to address their research question. RCT also called as true- experimental research-design is a quantitative research that involves manipulating the experimental group with intervention (diet control plus physical activity); a control group (without intervention) as well as randomization by allocating samples to both the groups (control experimental group) in a random basis (Fink, 2013) and hence it is of higher value as compared to that of other quantitative studies. According to Yartsev (2017), this RCT design will help to draw comparison between two groups. As the researchers have adopted this design, they can appropriately compare the study group (with intervention) and control group (without intervention). Thus, the research design they have adapted is adequate and can provide the strongest evidence to practice in a psychiatric setting. Ethical issues Ethics are the system of standards that is concerned with the extent to which the study follows the professional, legal, ethical as well as societal aspects to the study participants (Polit, 2016). A researcher has to get ethical approval from an Ethical Committee before commencing (Tappen,2010). In this study, the researchers have carried- out the study in-accordance with the Helsinkis Declaration. Further, they got ethical approval from the Ethical Reviewing Committee of the Yu-Li Veterans Hospital. It is understood from the text that they have informed all the patients about the study and obtained written (informed) consent before proceeding. The ethical principles as beneficence, maleficience, autonomy, justice and respect (Houser, 2011) including right to withdrawal at any time without penalty is followed. Bias control Bias is any influence that affects the study results and undermines validity (Polit, 2016). Controlling bias plays a significant role in obtaining high evidenced data so as to be utilized undoubtedly in patient practice. The researchers should try to avoid the maximum possible bias to ensure the quality of finding (Houser, 2011). Similarly, the researchers of this study have tried to avoid bias by following few methods. The participants in this study have distorted behavior (lack of condor) which could affect the researchers from obtaining information. Hence, the researchers have intelligently measured only anthropometric, metabolic and enzyme assays to avoid bias. Researcher subjectivity that involves pre-judging the expected finding and communicating to participants, but it could not be possible as the patients had distorted behavior. In regard to sample imbalances (sample bias/ faulty samples), the researchers have meticulously avoided bias by adapting random sampling technique to give equal chance to every participants. Sometimes, faulty methods of data collection could create bias. In this study, they have collected anthropometric data by a single investigator and have followed the directions in labels of chemicals for tests done to avoid bias. But, they have mentioned about the validity of the chemicals they have used for various tests anywhere which may increase the chance of bias. There could be possible measurement bias during anthropometric measurements due to inappropriate measurement tapes and improper observation. They have used RCT trial to avoid bias by manipulation, keeping controls and randomizing. Validity of variables Confounding variables are the extraneous variables that affect the relationship between study variables and hence should be controlled (Polit, 2016). The use of biological measurements in this study requires controlling these variables to avoid bias. Blinding that involves masking the individuals those involved in the study from getting information about the samples, the intervention modalities and/or the study-investigators to reduce bias which is not done here (LoBiondo-Wood Haber, 2014). They could have blinded at-least the investigators to control confounding variables. They have not controlled confounding variables by blocking/stratifying, crossover or homogeneity but have controlled by adapting variance with covariance (ANCOVA) analysis. The scientific merit of a quantitative study is measured by assessing the reliability and validity of the study instruments. But, validity and reliability was not shown for the instruments in this study which questions the scientific merit of the study. In regard to internal validity, they have supported their findings with other studies to show that there is a causal association between exposure (diet control plus physical activity regimen) and outcome (reduced BMI, body weight, waist hip- circumference, level of triglyceride, insulin level, with IGFBP-3 levels). This proves causality (i.e. cause and effect) relationship between variables. The researchers have also proved the internal validity of findings by drawing statistical difference between control and study group and hence could be practiced in psychiatric settings. In case of external validity, the validity that inferences about the relationships observed over the variations in settings, individuals, and study-time or measu re outcomes has to be accounted (Houser, 2011). In this study, they have proved their external validity by conducting the study in the same hospital, individuals with same diagnosis and measure outcomes. Only the duration of study is lengthy by is unavoidable to get sufficient number of patients. Hence, the study is of externally valid and could be applied in similar settings. Yet, future studies are needed to prove the effectiveness of intervention/exposure in other settings. Statistical analysis According to LoBiondo-Wood (2014), statistical analysis is the process of organization as well as analysis of collected data using statistical methods such as descriptive and/or inferential analysis. Descriptive statistics that involves describing and summarizing data and inferential statistics that involves drawing inferences between variables were employed in this study which is highly appropriate (NewCombe, 2012). The researchers have performed a detailed analysis of the data collected based on their objectives by testing hypothesis. They have used tables to show the difference between control (N=25) and study group (N=28) regarding anthropometric measurements, metabolic hormonal and growth factor data at baseline, 3rd and 6th months for schizophrenia in-patients treated with clozapine which is adequate (Tappen, 2010). They have collected and analyzed only the clinical data but not the demographic data. Demographic data is highly important to understand the physical characteristics of the patient. It could be better if they could have included demographic data in calculation and could have associated it with the comparative findings. The anthropometric measurements such as weight, BMI, waist- hip-circumference with waist- to -hip ratio, as well as fat percentage related to weight of both the study and control groups doesnt differ significantly and hence the demographic characteristics of both the groups are similar, thus reducing participant bias. Moreover, the mean fat% among men in study group was 30.94.8 and in control group was 30.05.1 whereas among women of study group, it was 43.610.7 and in controls of 41.45.7, which shows that the fat% is similar in both groups, thus minimizing participant bias. But, if the overweight classification of WHO is considered (0.85 for women and 1.0 for men), on ly the female participants in this study could be considered to have central obesity which may alter the comparison of data between both groups. The comparative analysis of anthropometric, blood samples, metabolic and enzyme analysis at baseline, 3rd and 6th months between groups is highly adequate; though difficult particularly using variance with covariance analysis (ANCOVA) along with SPSS (statistical- softwares 10.0 version); based on general linear-type model. They have not given any statement about the acceptance or rejection of research/null hypothesis except mentioning about statistical significance. They could have included hypothesis statement in introduction as well as analysis, which is crucial for a quantitative study. Overall, their selection of appropriate samples by considering their anthropometrics and their method of calculation and comparisons at varied levels (baseline, 3rd 6th-month) and method of discussion is adequate except few issues. Findings, study-discussions, conclusions with recommendations Discussion of results and recommendations are an integral part of a research study (Moule, 2013). They have discussed each and every finding to show the usefulness of their intervention/exposure based on their objectives. They have showed a signification reduction in anthropometric measures and metabolic parameters except growth factor as a benefit of their intervention in study group. They could have included cardiovascular components in their study as they are much concerned about cardiac risks. They have discussed their strengths and weaknesses but they have not mentioned anywhere about validity and reliability of study measurements particularly blood and metabolic parameters. The conclusion of a study should clearly summarize and derive the study-findings as well as establish the importance of the findings (Pilot, 2016). They have followed all the principles of conclusion by stating about their findings with its importance. Their mention about the applicability of their intervention/exposure in reducing the metabolic and anthropometric parameters, normalizing some metabolic abnormalities, reducing hormonal disorders and attenuation of few neuroleptic adverse effects that includes sedation with reduced day-to-day activities is adequate. They recommend walking to all clozapine-treated schizophrenic patients to avoid obesity and in-turn cardiac complications; which are inexpensive. It could also be done alone or with no/less instructions from others. Pilot study which is small- trail run could have been conducted to rule out any alterations or additions to be done with entire research process. They have not given any recommendations for conducting similar studies in other psychiatric settings or with alterations in interventions/exposure. Overall, though there are certain demerits in this study, the study-results will definitely serve as a guide to the health professionals caring schizophrenic patients. It could be difficult for them to motivate schizophrenic patients to follow instructions, yet it could help them significantly to reduce weight and weight-related complications. Hence, continuous exposure/intervention of diet control along with physical activity regimen for six- months to clozapine-treated obese schizophrenic inpatients reduces the body-weight, BMI, waist- hip- circumference, triglyceride level, insulin, as well as IGFBP-3 levels. References Boswell, C. (n. d.). Chapter-14: The research critique process and the evidence based appraisal process. Retrieved from https://samples.jbpub.com/9781284079654/9781284108958_CH14_Pass03.pdf Fink, A. (2013). Conducting Research Literature Reviews: From the Internet to Paper. Retrieved from https://books.google.co.in/books?isbn=1483301036 Greenhalgh, T. (2010).How to read a paper: the basics of evidence-based medicine. (4th ed.). Wiley-Blackwell/BMJ Books: Oxford. Houser, J. (2011). Nursing Research. Retrieved from https://books.google.co.in/books?isbn=1449677444 LoBiondo-Wood, G Haber, J. (2014). Nursing Research: Methods and Critical Appraisal for Evidence-Based. Retrieved from https://books.google.co.in/books?isbn=0323100864 Moule, P Goodman, M.(2013).Nursing Research: An Introduction. Retrieved from https://books.google.co.in/books?isbn=1446293521 Newcombe, R.G. (2012). Confidence Intervals for Proportions and Related Measures of Effect Size. Retrieved from https://books.google.co.in/books?isbn=1439812780 Polit, D.F Beck, C.T. (2016). Nursing Research: Generating and assessing evidence for nursing practice. Lippincott Williams Wilkins: New Delhi. Tappen, R.M. (2010). Advanced Nursing Research. Retrieved from https://books.google.co.in/books?isbn=0763765686 THS. (2015). Epidemiology- Glossary of Epidemiological and Statistical Terminology: Tropical Health Solutions. Retrieved from https://www.tropicalhealthsolutions.com/statsglossary Yartsev, A. (2017).Advantages and disadvantages of RCT. Retrieved from https://www.derangedphysiology.com/main/cicm-primary-exam/required-eading/research -methods -and-statistics/Chapter%202.0.2/advantages-and-disadvantages-randomised-control-study-design