Research Methods Report

Topic 1: Energy Drinks – are they worth the risk? 

Research Methods Report

Your report must consist of the sections described below.

  1. Introduction

Use this section to introduce your topic. In particular, address the following:

  • Why were researchers studying this topic?
  • Summarise the research questions that the papers address.
  • How did the studies hope to address one or more of deficiencies (if any) in the current body of 
knowledge? (5 marks) Use your own words! 
There is no word limit, just ensure you address the points listed above. As a guideline, one to two paragraphs will be sufficient.
  1. Materials and Methods

In this section, address the following:

  • What type of study designs were chosen by the authors to address research questions? Name these study designs.
  • How were subjects chosen for the studies? How many subjects were there? What do we know about them (e.g. age)?
  • What efforts (if any) were made to control for potential confounding factors?
  • What variables were measured? Are there any issues which relate to the internal reliability and 
validity of the measurement processes used?
  • What types of statistical analyses were employed?
  1. Outcomes and contributions

In this section discuss the following:

  • What were the key results of the studies? What significance level was used?
  • How do these results contribute to what is known about the area of study? Summarise briefly 
what the authors say in that regard.
  • What are the factors which may influence or limit the drawing of meaningful conclusions from 
the studies? Summarise the key issues which relate to the internal and external validity of the results.
  • For one of the statistical procedures employed in one of the papers, discuss power and effect size 
using appropriate Minitab output. Instructions on how to do this are given on page 7 of this 
 Put full details of your power calculation in an Appendix
  • How did the authors choose to present their results? Were their tables and displays easy to 
follow? Were they helpful? Comment briefly.
  1. Conclusion

In this section draw some overall conclusions and provide your answer to the topic question. There is no word limit. As a guideline, one to two short paragraphs will be sufficient.

Power Calculation in Section 3Instructions:

Place full details of your calculation (Steps 1 to 5 below) in an Appendix. Also include a report style discussion in Section 3 of the report.

First of all, check whether the authors themselves discuss their study power.

Step 1.Identify a two-sample t-test or a paired t-test of interest among the results in one of the papers

Step 2.Decide whether a two-sided or one-sided alternative was used / would have been appropriate.

Step 3.Assume the significance level used by the authors, or else use α = 0.05.

Step 4.For a medium effect size (|d| = 0.5), use Minitab to calculate power for the chosen test at the sample size used by the authors:

  • Use standard deviation calculated at baseline, corresponding to a control group, or pooled, whichever one is given or appropriate.
  • Use that standard deviation and effect size to calculate the difference needed to produce the effect size.

Step 5.Comment on your result.

Suggestions for Topic One: Energy drink effects on BP and ECG study (Shah et al 2016a) – you can use results from Table 1 or Table 2. Pick one of the variables and consider the comparison between the placebo and the energy drink group. Alternatively, you can verify the authors’ claim regarding power. 
Energy drinks and ginseng clinical trial (Shah et al 2016b) – you could try to use SBP or DBP for the comparison between placebo and energy drink at one of the time points. 
C-energy study (Kozik et al 2016) – consider changes from baseline reported in Table 1 or Table 2.

Suggestions for Topic Two: Dark chocolate and blood pressure in high-risk patients study (Desch et al 2010) – you can verify the author’s claims regarding power. 
Dark chocolate and snack consumption study (Koli et al 2015) – consider completer analysis results in Table 1 (e.g. before-after difference in clinical SBP or DBP for the dark chocolate or control period) or Table 2 (e.g. before-after difference in serum glucose, insulin or cholesterol for the dark chocolate or the control period). 
Dark chocolate and prehypertension study (Petyaev et al 2014) – you could use Table 2 (e.g. before-after difference in Systolic or Diastolic for one of the groups). 



The researchers were interested in study the specific effects of the energy drinks that are increasingly becoming common in the global market. Most of the researchers who were involved in the three different articles were interested in developing understanding of the dangers that are associated with the energy drinks (Lacey et al, 2016). They were interested in this topic due to the fact that little knowledge about these drinks is known by the user despite their increase in the beverage market. In addition, they interested establish some of the effects of the energy drinks in the beverage industry.  The most common questions of the research that the three articles addresses include among others where there were some of the dangers associated with the energy drinks.  However, most specific the research question that the articles involved establishing where the energy drinks have a specific effects on the electrocardiographic and blood pressure.

These studies explores using the current addiction never of the most of the energy drinks which the previous studies which had been conducted on the energy drinks had not visited. The study hope to address this deficiency in the existing knowledge by relating the higher energy drinkers with the effects of withdraws of the energy drinks in their system for some time (Pelter et al, 2016).   This particularly define in the body of the current knowledge was initially missing and could be used to explain where there are considerably higher addiction of the energy drinks to most of the users. This current studies also hoped to address the link that existed between the high blood pressure patients and the considerably previous use of the energy drinks. This the study hoped to achieve by study specific addicts of most of the energy drinks and looking into their blood pressure while monitoring a trend in the relation between these two most important variables.

Materials and Methods

The authors of the different articles used the randomized double blinded designs which conducting the study. In all the three articles the authors designed there study and conducted the study though the use of a considerably randomized study choosing a random population and facing under study. The areas of the three studies were also selected on a randomized basis. In all the articles the authors used a specific age group population chosen at random and developed a baseline which the evaluation of the effects of the energy drinks on their blood pressure were measured (Pelter et al, 2016). The subject of the three studies were human. These subjects of the study were choses at random as well. There are three 3 different subjects that were selected for the study by the researchers in both the three articles. For instance, in all articles healthy volunteers from the age of 18-40 years of age were used for the study. The third article however used 14 subjects with mean age of 28.6 years. In the studies, the subjects were excluded from the study on the basis of pregnancy.  The participants were randomized into different phases of treatment (Lacey et al, 2016).

During the study several variables were measured establish the effectsof the energy drinks in the subjects that were considered for study. Some of the variables include the QTc intervals and the systolic blood pressure. Secondly, some of the variables that were considered for the study include, QT intervals, QRS duration, heart rate and the diastolic blood pressure of the subjects. All these variable of the study were measured against a single baseline of the study. In addition, all the parameters for the study were then evaluated at baseline period 1, 3, and 5 hours. This was then used to monitor some of changes that existed in energy drinks consumption against the blood pressure.

The researchers of the different articles employed the use of ANOVA to analyze the statistical variables of the research. Specifically, the researchers uses the two-way analysis of the variance ANOVA to allow for the significance of 0.10 in conducting the pair-wise comparison since the variables under analysis were considerably many and widely vary. In addition, the T- test was used in the bonferroni corrections of the outlier values that were obtained during the analysis. In addition, the study also involve the use of the two way (ANOVA) analysis to draw conclusion from the different values that were obtained on the different time point(Pelter et al, 2016).

Outcomes and contributions

The result of the study was positive confirming the hypotheses of the studies. There was considerable increasing the blood pressure among higher energy drinks consumer in all the three studies.  There was an increase in the QTc interval after an energy drink consumption among most of the subject who were considered for the study.  There may also an increase in the participant blood pressure level after the consumption of these drinks use for the study. According to the studies, certain energy drinks that were consumed at higher volume significantly resulted in an increase of the QTc intervals as well as the systolic blood pressure considerably over 6ms and 4mmHg respectively. This represented a considerably a higher percentage in blood pressure increase in a lifetime consumption of the energy drinks. There was a considerable decrease in the PR intervals in 2 hours after the consumption of these energy drinks during the studies. Pana ginseng which was also considered for most of studies did not record any significant change in the ECG or the participant’s blood pressure. A significance level of 0.10 was used in the three studies(Lacey et al, 2016).

These results confirms to the knowledge about this areas of study. It confirm some of the effects of the energy drinks on the levels of the blood pressure by confirm that actual effects to the blurred knowledge which was initially stating that these drinks have effects on the blood pressure by stating the actual effects. Considering the article 2 for the power sample size analysis for the calculations. See appendix.

Some of the factor which may influence the drawing an effective or meaningful conclusion from the studies is the lack of the uniformity of the drinks where the studies considered for the different studies under consideration. In addition, the differences slight difference which is experienced in the three studies regarding the significance of the energy drinks may also result be quiet confusing. The other factor that may limit drawing of a meaningful conclusions from the articles is based on the fact that they are not detailed especially on the long-term effects of the energy drinks. The results from the findings used on the three articles is just based on a short term analyses of few hours of 1, 3 and 5. The articles does not provide the longtime effects of the energy drinks under study on the blood pressure.

The authors the papers presented their findings in a table form which are considerably easy to follow and understand. The tables used to present the information were helpful. This is due to the fact that one could have one on one comparison of the issue of discussion from the table the researchers presented. In the articles 2 and 3 the presentation of the tables are considerably easy to make conclusion from. Article on the other hand does not present good tables for the purposes of analysis.  The table doses not stand alone unlike in the case of the other articles.


From the three articles, there is considerable effects which particular involve some dangers which are involve in the energy drinks consumption. The dangers particle involves an increase in the blood pressure and the electrocardiographic among the consumers. This possess a great health among the consumers of these drinkers which are considerably becoming more common among the beverages across the world. This is like to the increase in the emergency room visits in most of the Emergency departments ED as a result of these dangers related to blood pressure.


Shah, S. A., Occiano, A., Nguyen, T. A., Chan, A., Sky, J. C., Bhattacharyya, M., …& Nguyen, N. N. (2016). Electrocardiographic and blood pressure effects of energy drinks and Panax ginseng in healthy volunteers: A randomized clinical trial. International journal of cardiology, 218, 318-323.

Shah, S. A., Dargush, A. E., Potts, V., Lee, M., Millard-Hasting, B. M., Williams, B., & Lacey, C. S. (2016).Effects of single and multiple energy shots on blood pressure and electrocardiographic parameters.The American journal of cardiology, 117(3), 465-468.

Kozik, T. M., Shah, S., Bhattacharyya, M., Franklin, T. T., Connolly, T. F., Chien, W., …&Pelter, M. M. (2016). Cardiovascular responses to energy drinks in a healthy population: the C-energy study. The American journal of emergency medicine, 34(7), 1205-1209.


ANOVA Power Calculation Results           

Considering the first article subject for the calculation of the Minitab output and size power, the standard deviation in diastolic blood pressure between subjects was 27 for that study.  The researcher planning the study would like to know the total number of subjects that will be needed to detect a practical difference in the diastolic blood pressure between subjects taking the energy drinks and hose not taking the drinks.  A significance level of 0.10 and a power of 0.8 are desired. Mintab output result 4.67

Power and sample size

Testing mean= null versus alternative

Calculating power for mean= null+ differences

Alpha= 0.10 Assumed standard deviation= 27

Sample size   target power

40                         0.8              = 32

The actual power = 32