Critical Appraisal of a Published Epidemiological - Article Example

Critical Appraisal of a Published Epidemiological Paper Insert (s) Critical Appraisal ofa Published Epidemiological Paper Introduction The article titled “Active tuberculosis case finding and detection of drug resistance among HIV-infected patients” by Alemayehu, et al.( 2014) primarily sought to investigate the prevalence of undiagnosed cases of pulmonary tuberculosis among HIV infected patients and the resultant development of multi-drug resistant TB (MDR-TB). Tuberculosis is an opportunistic infection common among HIV patients and co-infection usually occurs when an individual has HIV infection as well as a latent or active tuberculosis disease. In such cases, both diseases often speed up the progression of each other thereby increasing the risks of deaths among co-infected individuals. According to Alemayehu et al. (2014), Tuberculosis patients co-infected with HIV virus normally lack the classic symptoms of pulmonary TB thereby making it significantly difficult to detect the disease before at its latent stages before it fully progresses to active form. According to many experts, this is particularly attributed to the fact that HIV infection usually results in a damaged immune system which then ultimately alters the normal history and progression of opportunistic infections like pulmonary Tuberculosis (Lawn and Gavin, 2009, p.325). As a result, the risk of progression from latent to active tuberculosis is significantly higher and is in some cases estimated to be 20 times greater in HIV patients than among normal patients. Alemayehu et al. (2014) also noted that this is particularly common among in resource limited settings whereby the co-infected patients may only be diagnosed when they begin to critically manifest the symptoms of the disease, resulting in delayed diagnosis and continued transmission. The research was done by seven authors from different institutions; University of Gondar, Armauer Hansen Research Institute and the Emory University in the year 2014. The title of the research is appropriate and focuses on a critical issue. Tuberculosis being one of the opportunistic diseases to people infected with human immunodeficiency virus (HIV) has received a lot of attention in terms of research in different parts of the world (Martinson, Hoffmann and Chaisson (2011, p.288). Generally, the authors have fairly covered all the key aspects of the research using a cross sectional research approach. In addition, the research question has also been adequately answered. This paper offers a critical appraisal of the study with particular focus to its rationale, methods used, the accuracy of the findings as well as the validity of the interpretation of the results and conclusions In addition, the appraisal will also be focusing on the interpretation of the results and their relevance in relation to similar studies. Methods The researchers primarily employed a cross-sectional research design to prevalence of undiagnosed cases of pulmonary tuberculosis among HIV infected individuals in a TB endemic region of Gondar, in Northwest Ethiopia. The cross sectional study which was carried out between February, 2012 and Nov., 2012 particularly involved a total of 250 participants randomly selected from among HIV infected patients who were aged 18 and above. With regard to data collection, the researchers collected both clinical and social-demographic data using structured questionnaire. In addition, sputum samples were also collected from each of the participants for TB and drug susceptibility tests. This kind of research design is consistent with the recommended research methods for similar epidemiological research studies seeking to investigate the prevalence of diseases and their outcomes (World Health Organization, 2009). The research method adopted by the researchers provided the necessary tools to get a snapshot of the prevalence of undiagnosed cases of pulmonary tuberculosis among HIV infected individuals in the area of Gondar at the particular point of time. The strengths of the methodology are the sophisticated methods of sputum analysis. Methods such as molecular typing, mycobacterium culturing and drug susceptibility testing were also used in the right way and for the right purpose. The treatment of the data collected was done in a way that brought out all the variables tested for. SPSS software usage in analysis of the descriptive data reported the socio-demographics which the research sought. According to Bland (2012), the use of regression in creating a relationship between variables also gives this research strength. On the other hand, the authors were also able to effectively address the issue of ethical consideration in the research by seeking approval from relevant ethics boards and ethics review committees as well as obtaining informed consent from the participants before undertaking the study. One possible weakness of the study in this aspect is that the researchers failed to indicate whether the respondents were assured that the anonymity and confidentiality of the information they provided would be protected. Generally, ethical consideration is normally one of the most important aspects of a credible research. According many experts, a good research design must not only be ethically justifiable but should also be based on prior informed consent from all the relevant parties involved in the research process (Hickson, 2008, p.45). It is also important to ensure that the anonymity and confidentiality of the information disclosed by the participants in a research are protected to ensure their privacy. Although the research method used was fairly appropriate to the study design, a major limitation of this approach is that the cross sectional design used lacked the time element as it is only restricted to a particular point of time (between February, 2012 and November, 2012). In this regard, the research method chosen by the researchers cannot effectively give an indication of the sequence of events nor can it show whether the HIV infections occurred before, after or during the onset of the active pulmonary tuberculosis in the participants. However, this research limitation can easily be well taken care of by conducting repeated cross –sectional studies where the participants can either be from different or the same sampling frame in order to give a pseudo-longitudinal study. On the other hand, another likely limitation of the method adopted is that makes the research to be significantly more vulnerable to prevalence-incidence bias (which is also popularly known as the Newyman bias). For example, in the case of long lasting diseases like HIV and tuberculosis, any potential risk factors that may also speed up the progression of latent pulmonary TB to active pulmonary tuberculosis may not be taken into consideration in the research. Finally, another potential limitation of the research method used in the study is that the sample size of 250 participants was relatively small and may not be representative of the targeted population. While the small sample size enabled the researchers to complete the research within such a short time frame, a slightly larger number of participants would have been more statistically sound as it leads to narrow statistical intervals and therefore, more precise results. For example, a similar study conducted in Kenya Vant Hoog et al. (2012) used 40 clusters of 20,000 participants in the period between August 2006 and December, 2007. Another research conducted in Brazil by Golub et al. (2008) used a larger sample size of 1080 infected patients. Results The results of the study were generally accurate as the researchers employed fairly appropriate statistical analysis in deriving their findings. For example, following the case finding of active TB, a total of 15 out of the 250 (6%) of the participant cases were recorded as TB cases. 9 out of the 250 cases were detected using both culture and smear microscopy techniques while the remaining 6 cases were only detected using only culture. This study by Alemayehu and others had an overall aim of determining the prevalence of the undiagnosed pulmonary tuberculosis and the multidrug- resistant TB (MDR-TB) within patients infected with HIV. The sample size for the study included a total of 250 patients infected with HIV who are not below the age of eighteen. Data collection was by use of questionnaires and sputum analysis. The results showed that six percent of the sampled sputum test positive for TB while the undiagnosed pulmonary tuberculosis was at 4.4%. On the other hand, a multivariate logistic regression was used to determine whether there was a statistically significant association between the occurrence of pulmonary tuberculosis and other opportunistic infections such as pneumonia. The method of analysis used in the research ensured the accuracy of the results and findings through a number of reasons. First and foremost, the multivariate logistic regression statistical analysis allowed the researchers to effectively include more than one dependable variable in their analysis. In addition, the researchers were also able to use logistic regression to provide more quantified value for the strengths associated with the other variables. Generally, In the review, Alemayehu, et al.,( 2014) needed to find out the prevalence of undiagnosed tuberculosis in HIV positive patients that had not been detected and as such patients were not aware pulmonary tuberculosis illness in Gonda, North West Ethiopia. In most cases, Tuberculosis patients who are co-infected with human immunodeficiency virus have been found not to have the classic symptoms of tuberculosis as such diagnosis becomes difficult and patients appear when the disease has progressed and has taken a tall on their health (Lawn and Gavin, 2009, p.328). According to many researchers, the accuracy of the research findings often depend on a number of key aspects namely the credibility of the information and the believability of the findings. For example, in the study, the researchers have improved the believability of their research findings by providing adequate description of the participants particularly with regard to their social-demographic backgrounds and settings. This is critically important as it allows the readers of the research study to draw their own conclusions thereby further enhancing the credibility of the research study. In addition, the authors have also effectively highlighted the correlation between the various data sources such as the culture and smear microscopy results with the social-demographic backgrounds of the participants obtained using structured questionnaire. The use of multiple sources of data collection such as structured questionnaire and culture and smear microscopy has to some extent enabled the researchers to minimize the potential occurrence of biasness by providing the findings from different perspectives. On the other hand, the confirmability of the re3sults and findings of the research has been particularly improved by the documentation of all the procedures and processes used during the cross sectional study. This makes it much easier to authenticate the accuracy of the data used throughout the research study. In addition, the documentations also provide important insights for the readers to understand how the researchers may have arrived at certain conclusions. Lastly, the use of a cross-sectional design is an appropriate method as it took into account the case of 250 HIV patients of age 18 years and above for aperiod of February 2012 to November 2012. These patients were monitored by use of both clinical signs and biometric examination. By use of first-line anti-tuberclosis drug susceptibility was done to patients who were found to be culture positive for tuberculosis. This method therefore was appropriate in isolating the required data that was useful to the study. Various researchers have used various research designs such as experimental designs as well as retrospective designs, the design used by Alemayehu M, et al. instrumental in achieving the required results. There are a number of important aspects that the results of the study can effectively add to the field of epidemiology particularly with regard to the difficulty in detection of the progression of TB among HIV patients. First and foremost, the researchers have revealed a considerably high rate of prevalence of diagnosed cases of pulmonary tuberculosis among HIV infected individuals. This is a likely suggestion that the current passive TB case finding is not up to the required standards (Lawn and Gavin, 2009, p.327). As a result, there is an urgent need to improve and intensify active screening of HIV-infected individuals, especially those suspected of or who have shown at least a single symptom of pulmonary tuberculosis in order to mitigate the risk of progression from latent to active tuberculosis as well as limit new infections. This may be critically important in resource limited settings whereby the co-infected patients may only be diagnosed when they begin to critically manifest the symptoms of the disease, resulting in delayed diagnosis and continued transmission. Generally, case finding as well as the treatment of any symptomatic patient is currently one of the core elements of the contemporary global tuberculosis control strategy as recommended by the World health organization (WHO, 2009). Discussion The discussion part of the research is well written and the authors have interpreted their findings in a fairly accurate manner. In addition, it is also important to note that the researchers have presented and discussed the findings and results of their study in an appropriate way that is both easy to read and understand. For example, based on an interpretation of the findings, the authors concluded that the prevalence of undiagnosed pulmonary tuberculosis was at 4.4% while six percent of the sampled sputum test positive for TB. Additionally, the researchers concluded that the possibility of these undiagnosed incidences of pulmonary tuberculosis can pose a significant risk for the transmission of the disease especially among family members. Finally, the researchers recommended continuous active screening of HIV-infected individuals, particularly those suspected of or who have shown at least a single symptom of pulmonary tuberculosis in order to mitigate the risk of progression from latent to active tuberculosis as well as limit new infections (Martinson, Hoffmann and Chaisson (2011, p.290). These conclusions are consistent with the findings of a number of other previous studies. For example, a similar empirical research conducted by Vant Hoog et al. (2012) in Kenya revealed that HIV and TB con-infection often result in the two diseases speeding up the progression of each other thereby increasing the risks of deaths among co-infected individuals. In addition, Alemayehu et al. (2014) also suggested that Tuberculosis patients co-infected with HIV virus normally lack the classic symptoms of pulmonary TB thereby making it significantly difficult to detect the disease before at its latent stages before it fully progresses to active form. For example, in the study it highlights that there would be even more cases if the use of active case finding method would be used. This shows that there was a close relation of the HIV positive patients to undiagnosed tuberculosis and increased chances of drug resistance. The author further argues that as a result, the risk of progression from latent to active tuberculosis is significantly higher and is in some cases estimated to be 20 times greater in HIV patients than among normal patients. This is particularly true and other previous researchers have attributed this to the fact that HIV infection usually results in a damaged immune system which then ultimately alters the normal history and progression of opportunistic infections like pulmonary Tuberculosis (Vant Hoog et al., 2012). Pulmonary tuberculosis has been found to be a major concern in the current world and more so in people who are human immunodeficiency virus (HIV) positive. It has been found that detection of the symptoms is done at a far much later stage whereby the tuberculosis disease has caused a lot of health damage and to an extent resulting to drug resistance (Golub et al., 2008,). . At the same time, the authors’ findings and interpretation have been found to support the study and as such useful in relation to the study question and objectives of the study in finding out the prevalence rate of undiagnosed tuberculosis in HIV patients (WHO, 2009). Finally, the authors have covered this aspect comprehensively by trying to understand the setting and the relation it has in a scarce-resource area such as Gonda in Ethiopia. By looking at tuberculosis Endemic areas the authors have narrowed down their study to come up with the findings. From this aspect therefore the authors’ research question was, what is the prevalence of undiagnosed tuberculosis among people who are infected with human immunodeficiency virus at Gonda in Ethiopia. In the recent studies it remains an issue of concern as it has been isolated that increased cases of multidrug resistance for tuberculosis treatment has been associated with delayed diagnosis in HIV positive patients (Martinson, Hoffmann and Chaisson (2011, p.291). Researchers also concur that tuberculosis patients co-infected with HIV virus normally lack the classic symptoms of pulmonary TB thereby making it significantly difficult to detect the disease before at its latent stages before it fully progresses to active form. According to Golub et al. (2008), this is particularly attributed to the fact that HIV infection usually results in a damaged immune system which then ultimately alters the normal history and progression of opportunistic infections like pulmonary Tuberculosis However, much effort need to be put on early diagnosis of the disease in HIV infected people and use of proper diagnostic equipment and methods. In order to avoid continued infection among various patients it has become important to diagnose tuberculosis early enough. Many studies highlight that there is more risk when high cases of undiagnosed tuberculosis exists among people who are HIV positive and largely affects patients response to various drugs and ability to lead a healthy life. In my opinion, future studies seeking to investigate similar variables should address the major limitation of the current research by carrying out multiple and repeated cross-sectional studies where the participants can either be from different or the same sampling frame in order to give a pseudo-longitudinal study. Conclusion In conclusion, the study has fairly covered all the key aspects of the research including the relevant research questions based on a cross sectional research approach. The research method adopted by the researchers provided the necessary tools to get a snapshot of the prevalence of undiagnosed cases of pulmonary tuberculosis among HIV infected individuals in the area of Gondar at the particular point of time. Lastly, the results of the study were generally accurate as the researchers employed fairly appropriate statistical analysis in deriving their findings. However, the study also had a few limitations such as the fact that the cross sectional design used lacked the time element as it is only restricted to a particular point of time and small sample size. References Alemayehu M, Birhan W, Belyhun Y, Sahle M, Tessema B. 2014. Active tuberculosis case finding and detection of drug resistance among HIV-infected patients: A cross-sectional study in a TB endemic area, Gondar, Northwest Ethiopia. J Microb BiochemTechnol 6, 179-184. Bland, M. 2012.  An Introduction to Medical Statistics. 4rd Edition. Oxford: Oxford University Press. Golub, J.E, Durovni, B, King, B.S .2008. Recurrent tuberculosis in HIV-infected patients in Rio de Janeiro, Brazil. AIDS. 22(1):pp.2527–2533. Available at Hickson, M. 2008. Research Handbook for health care professionals. Manchester: Blackwell Publishing. Lawn, S.D. & Gavin, C. 2009. Epidemiology of HIV-associated tuberculosis Running Head: Epidemiology of TB /HIV. Curr Opin HIV AIDS 4(4): pp. 325–333. Available at Martinson N.A, Hoffmann C.J, Chaisson, R.E. 2011. Epidemiology of tuberculosis and HIV: recent advances in understanding and responses. ProcAm ThoracSoc 8: 288–293. Available at Vant Hoog A.H, Williamson, J, Sewe M, Mboya, P, Odeny, LO, Agaya, J.A, Amolloh, M,, Borgdorff M.W, Laserson, K.F. 2012. High Prevalence of Pulmonary Tuberculosis and Inadequate Case Finding in Rural Western Kenya. American Journal of Respiratory and Critical Care Medicine 183(9): pp. 1245-1253 Available at World Health Organization. 2009. Guidelines for Surveillance of drug Resistance in Tuberculosis. Geneva: WHO Report. Read More