Assessment Of Green Tea Benefits: PICO Model Essay


Write about the Assessment of Green Tea Benefits for PICO Model.



Tea originated in China, over 4000 years ago. Tea was initially used in the form of medicine. Later on it became a widely used beverage during the Han dynasty. The medical benefits of green tea consumption include cancer prevention, antiarthritic, anti-inflammatory, antibacterial, antioxidative, neuroprotective properties. These health promoting effects are due to the presence of polyphenol (flavonols and flavanols). This essay aims to provide a critical analysis of the probable effectiveness of green tea in reducing cancer, when compared to black tea in young women.

Search terms

Evidence based practice methods or questions related to clinical research need to be relevant to topic of interest. It should be designed in a way to simplify the search for the solution. PICO model makes this an easier task (Boehm et al., 2016). PICO is a mnemonic for the essential aspects of a clinical question. It identifies the key concepts of the article and formulates different search strategies to address the question (Liamputtong, 2013). The PICO model is mentioned in Table 1.

Table 1- Key words used in PICO model





Population (young female)

Females of the age group 18-40, young females, adult females.


Intervention (use of green tea)

How to drink green tea, green tea consumption


Comparison (medical benefits of green tea and black tea)

green tea and cancer, cancer and herbs


Outcome (Improvement of Effect)

Green tea, black tea anticancer

Information source

Two kinds of literature sources are available for clinical research. A primary literature in refers to journal articles, which report an original project and are written by experts and commercially published. These articles are reviewed. Secondary literature, like textbooks and encyclopedias analyze and interpret the primary sources (Stretton, 2014). Appropriate utilization of sources is essential for clinical research. For information on the possible anticancerous and herbal effects of green tea, the Cochrne library and the DIACAN database were used. Cochrane Library is helpful for healthcare professionals in addressing effectiveness of disease outcomes (Kontopantelis, Springate & Reeves, 2013). DIACAN is an Integrated Database for Antidiabetic and Anticancer Medicinal Plants. It collects and provides a platform for phytochemicals extracted from plants, having antidiabetic or anticancer activity. Presently, cancer is one of the major causes of mortality and affects more than one-third of the world’s population. Phytochemical effects of natural products in anticancer drug discovery are quite prominent (James et al., 2013). These two databases will help in understanding the direct potential anticancerous benefits of green tea and its effectiveness in the target population for the case study.

Search process

Credibility plays an important role in clinical research. Credible sources and databases can change opinion and attitudes. Critical evaluation of the information available is needed to conduct clinical research. Firstly, all key terms were searched individually under the Natural Medicines Comprehensive Database. No limiters were included. Therefore, several related articles were obtained. Boolean operators like ‘AND’, ‘OR’ were applied to the database to narrow the search results to topics that contain only the required information. Firstly, the Boolean phrase ‘OR’ was used (‘green tea OR black tea) in between the key words, which displayed in large numbers of evidences. To narrow down the search results, the search terms used later on were ‘green tea AND cancer’ and ‘green tea AND anticancer properties’. This eliminated displaying of unwanted results. Therefore, limiters or filters were used to further refine obtained search results. It was done by filtering the search results to recent publication dates (from 2008). After following these techniques to refine the search, numerous relevant articles were obtained. Thus, these specific and selective results enabled precise answering of the PICO model. The search process using the Natural Medicines Comprehensive Database is mentioned in Table 2.

Table 2- Steps for narrowing search results






Females of the age group 18-40 drinking tea OR young females drinking tea

Searched all items


No limiters


green tea consumption OR health

Searched all items


No limiters


cancer AND herbs

Searched all items


Limiters used


green tea OR black tea AND cancer

Searched all items


Limiters used



Searched all items


Limiters used



Limiters used

Published Date: 2008-2017


Limiters used

Published Date: 2008-2017

(Source- Richardson?Tench et al., 2016)

Best search result

In this scenario, after utilizing the PICO model questions and limiting the search in the Cochrane library database, the evidence entitled “Green tea (Camellia sinensis) for the prevention of cancer” was found to be the best for the purpose of providing answers to the questions in the PICO model. This review was found in the Cochrane database of systematic reviews after searching the database with the limiters mentioned in the S6 hierarchy level. The review contains elaborate information on the anticancerous effects of catechin, an antioxidant found in polyphenol (the active ingredient of green tea). It used controlled interventional and observational studies to assess the link between incidence of cancer risk and consumption of green tea by several randomized trials (Boehm et al., 2009). The evidence was insufficient and conflicting to provide any information on the potential anticancerous benefits of green tea.


Thus, it can be concluded that for any clinical trial or research, healthcare professionals or researchers need to develop and implement a plan according to the PICO question model. They should utilize the best of resources available by limiting their search results to relevant topics. Narrowing search results provide better credibility of sources in formulating the outcomes.


Boehm, K., Borrelli, F., Ernst, E., Habacher, G., Hung, S. K., Milazzo, S., & Horneber, M. (2009). Green tea (Camellia sinensis) for the prevention of cancer. The Cochrane Library.

Greenhalgh, T., Bidewell, J., Crisp, E., Lambros, A., & Warland, J. (2016). Understanding Research Methods for Evidence-Based Practice in Health 1e.

James, P., Mathai, V. A., Shajikumar, S., Pereppadan, P. A., Sudha, P., Keshavachandran, R., & Nazeem, P. A. (2013). DIACAN: integrated database for antidiabetic and anticancer medicinal plants. Bioinformation, 9(18), 941.

Kontopantelis, E., Springate, D. A., & Reeves, D. (2013). A re-analysis of the Cochrane Library data: the dangers of unobserved heterogeneity in meta-analyses. PloS one, 8(7), e69930.

Liamputtong, P. (2013). Research methods in health: foundations for evidence-based practice.

Lodi, G., Franchini, R., Warnakulasuriya, S., Varoni, E. M., Sardella, A., Kerr, A. R., ... & Worthington, H. V. (2016). Interventions for treating oral leukoplakia to prevent oral cancer. The Cochrane Library.

Richardson?Tench, M., Taylor, B., Kermode, S., & Roberts, K. (2016). Inquiry in health care.South Melbourne, Australia: Cengage Learning.

Stretton, S. (2014). Systematic review on the primary and secondary reporting of the prevalence of ghostwriting in the medical literature. BMJ open, 4(7), e004777.

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