1. Define the terms ‘bias’ and ‘confounding’ in relation to quantitative public health and health services research . Hepatitis B is a severe liver infection that if left untreated leads to fatality and/or death. Due to the seriousness of the disease there are a plethora of prescription drugs available to help ease the symptoms of Hepatitis B and perhaps ultimately dissolve the disease entirely. In recent times the homeopathic appeal of medicine has been influencing the way many that suffer with diseases treat their ailments. Many are realizing the pharmaceutical approach to treating illnesses is dangerous and ineffective a lot of the time. In a study contributed by; Winnie Wing-man Leung, Suzanne C Ho, Henry L Y Chan, Vincent Wong, Winnie Yeo and Tony S K Mok it proved that regular coffee consumption reduces the risk of hepatocellular carcinoma in hepatitis B. Hepatocellular carcinoma is ‘a cancer that starts in your liver. It’s different from secondary liver cancers, which spread to the liver from other organs’( WebMD) . The study argues that the regular consumption of coffee has a protective attribute to it and the reduction risk ranged from thirty to eighty percent. The study was done from late 2007 to mid 2008 in Hong Kong where two hundred and thirty four HBV carriers were studied determining whether coffee reduced the risk of hepatocellular carcinoma. The data collection for the study included medical history consisting of medical records and first person interviews. The control variables in the study include; age, gender, cigarette smoking, alcohol use, tea consumption and physical activity so that the results are not altered. A bias in a quantitative public health research is an error where research digress from authentic research. Possible ways bias’ can come into play is during the interview process or during the process where the subjects of the study are selected. An example of a bias would be if a lip balm company was conducting a study on the effectiveness of their new formula infused with almond oil. Further, the lip balm company would recruit one hundred women between the ages of thirty and thirty five. Fifty of these women are not taking a medication that causes dry mouth while the other fifty are taking the medication that gives them that symptom. This would be a blatant bias because half of the subjects are already exposed to having drying lips and mouth because of their medication, this fact would alter the information derived from the study. Confounding definition in health services research is when there is no control variable of the study, similar to a bias, but is more oblivious in nature. An example of this would be if a paintbrush company where testing the steadiness of their new paintbrush but they brought in subjects who had arthritis and compared their handwork with those without arthritis.
2. Describe the steps taken to minimise bias and confounding by the authors.
The steps taken to minimise a bias in a study with several contributing authors is to first establish what the dependent and independent variables are. This is important because it creates a clear goal of the study and allows for those conducting the research to have constant factors in a study. When there are several authors conducting the same research and putting it together for one cohesive quantitative or qualitative study, it is important to have concrete variables so that data can not vary too much. The next step to minimise bias would to construct a study where the experimenter is carefully keeping a control variable that was established during the beginning stages of putting together the study. After the study concludes all those involved should double check for the credibility of the information gathered. Despite being thorough in a study, it is impossible to have complete control over a study and the subjects involved because of the nature of life and humans. This does not excuse error in data. As a matter of fact, having contributors compare data and analysis with each other is significant in minimising bias because it employs the knowledge and background information of numerous professionals.
3. Describe any remaining sources of bias and confounding that the study may still be open to. Any remaining factors that would cause bias or confounding results by the authors would be human error. For an example if a study is researching a new hair serum for women over fifty a variable out of the control of the researcher may be that some of the women are using a shampoo that dries out their hair more than other shampoos or some subjects may consume more nuts than others, which promotes moisture. The habits and daily routines of the subjects, in this example and many examples the subjects are humans, play a key role in scientific effects taking place. Medical background also plays an important role during scientific experiments involving living subjects because it has an effect on the outcome of the research and study. For an example, if someone where extra sensitive to caffeine resulting in shaking or increased anxiety it will have an effect on the outcome of the protective agent coffee contains. Concerning the coffee and hepatitis B study, the subjects that are carriers of the disease may be taking extra medications or health remedies that affect the protective agents in coffee consumption.
4. Briefly describe one alternative study design that could be used to determine if moderate coffee consumption reduces the risk of hepatocellular carcinoma in chronic carriers of hepatitis B.
An alternative study that would support the coffee consumption and hepatocellular carcinoma reduction risk would be by conducting a study than replaces hot coffee with iced coffee. The alternative study will explore the depth of the protective agent in coffee against hepatocellular carcinoma in chronic carriers. If coffee consumption is as valid as the original quantitative study promotes, the temperature of the beverage should not have a significantly negative effect. The carriers will consume iced coffee instead of hot coffee and the experimenters could see if it has the same effect, a lesser effect or no effect at all. Essentially, the experiment will be looking if temperature is pivotal in the protective agent or if it is irrelevant. Because coffee is the the active factor in the reduction of the disease, the temperature of the beverage should not make much of a difference so as a result it should yield identical or at least a similar outcome. The alternative study will design questions, hypotheses and experiments around that fact and make note if the temperature does have a larger effect than anticipated.
5. Discuss the pros and cons of the alternative study design proposed in section 4. Include, but do not limit your discussion to, issues of bias and confounding. When discussing the pros and cons of the alternative study by using the iced coffee as the protective factor over hot coffee it appears that the pros outweigh the cons. The pro is that the study would have very little to alter from the original. The subjects would remain untouched and so would the product, coffee. Mainly, the only thing that would change would be the temperature it is served at and the preferences and disorders of the people being evaluated. Perhaps the most challenge the researcher would face when collecting a focus group is possibly switching out subjects who are opposed or cannot handle the consumption of iced coffee. It is common amongst more traditional coffee drinkers to have a dislike for iced coffee and especially do not like to drink it in the morning. This has the possibility to cause an error in the data because if someone doesn't like something, they will not be committed to drinking it like the way they would something they liked. Also, many people like to drink hot coffee in the morning because it wakes them up, while the intensity of cold drinks in the morning makes many people upset. Another possible roadblock when using iced coffee instead of hot coffee in the experiment is considering the subject who may have dental sensitivity. Many of those suffering from dental sensitivity cannot handle cold food and beverages because it gives them the sensation of a toothache. Subjects who are suffering with that problem will possibly refrain from drinking iced coffee because of the sensitivity. That is the interesting thing when conducting experiments, those involved have to remember that studies involve people a lot of the time and human factors that create imperfection do have a key role in the data received. That is why it is important for all researchers involved to verify all components of the experiment to ensure authentic data and information received.
6. A further case-control study reported the following results: of 209 individuals with hepatocellular cancer, 135 reported they did not drink any coffee; of 1583 individuals without hepatocellular cancer, 1257 reported they did drink coffee. Calculate the odds ratio of the risk of hepatocellular carcinoma in those who did versus those who did not consume any coffee. Show your working. Interpret your result.
In a further case-control study the reported results had two hundred and nine individuals with hepatocellular carcinoma and one hundred and thirty five pupils were recorded to have not consumed coffee. Of the one thousand five hundred eighty three without the disease, one thousand two hundred and fifty seven did drink coffee on a daily basis. The odd ratio is calculated by multiplying ‘a’ by ‘d’ and then by dividing by the sum of ‘b’ multiplied by ‘c’. In this case one hundred and thirty five is ‘a’, two hundred and nine is ‘b’, one thousand two hundred and fifty seven is ‘c’ and one thousand five hundred and eighty three is ‘d’. So to obtain the odds ratio, one hundred and thirty five will be multiplied by one thousand five hundred and eighty three to end up with 213,705. This number will be divided by the sum of multiplying two hundred and nine by one thousand two hundred and fifty seven which would be 262,713. The end product is calculated to be 0.8134 which computes to roughly eighty one percent. Essentially, the odds ratio is eighty one percent showing that coffee consumption does have notable effect on carriers of HBV. This study was also done in Japan and Europe according to the text, which also had consistent results with the study done in Hong Kong.
Part 2 Question: Does regular coffee consumption reduce the endangerment of hepatocellular carcinoma in hepatitis B in chronic carriers?
Setting: The hospital where the quantitative study was conducted, so that the setting can remain a control variable.
Design: The design of the study will research the subjects consuming the coffee on a regular basis and will be seeing if it has an effect on the risk of hepatocellular carcinoma. Essentially, the research experiment will not be testing for a cure, but for a prevention agent. The design will be similar to the quantitative study in terms of the procedures and the way the data is collected.
Before the study beings medical history, habits and daily routines will be documented for each subject participating in the study. Factors like smoking, heart disease, regular exercise or anything else that may have an effect of the results should be documented for data collection and reasons concerning bias. Eliminating bias in a study ensures authenticity and accurate information which is the most important aspect of scientific research. The study will take place over a course of a month and will be split into two groups at the hands of random selection, where subjects will come into the the hospital twice every week and report the amount of coffee they have consumed. The amount consumed will be measured in cups, for an instance, one subject may report that they drank four cups of coffee total on the first data collecting day of the week. The other group will be prohibited from drinking coffee but will still come in on all data collecting days so that an update on medical history and daily routines can be documented. The coffee consumption group’s medical background, information and daily routines will also be documented on examination days.
On examination days throughout the month the coffee consuming group, here will hereby be known as ‘group A’, will report the amount of cups consumed on each examination day. While at the hospital they will also document their medical history, information and daily happenings. If nothing changes they inform the researcher that nothing has changed. If it has, for an example if one of the subjects apart of group A got the stomach flu, they would let their researcher know so that it can be documented. Changes in health and routine will be considered when tallying up results and writing up the paper and study after the month has concluded. Group B, the group who is not allowed to consume coffee, will do the same as group A except for informing the authors how much coffee they have consumed, for they are consuming zero cups throughout the month. At the end of the month the number of cups consumed from group a will be calculated subject by subject. To illustrate the calculation process I will use the following example; Howard: 40 cups, Elizabeth: 27 cups, and so on and so on. After the amount of cups consumed are collected and documented, they will be tested for the presence of hepatocellular carcinoma, subject by subject. Once all of those numbers are tallied, they will be added together then divided so that the researchers can have a percentage and create a ratio to compare to group B. Once the results are overlooked by all contributing authors, they will be typed up in research paper of study showcasing the results collected by the two participating groups.
Essentially, the design of the two studies will have very little differences except for the data recorded which will focus more on the symptoms of hepatocellular carcinoma which are non-numerical like; loss of appetite and yellowing in the skin and eyes.
Population/Sampling/Recruitment: The study group will remain the same for the simple fact that the data collected has to stay constant so that the non-numerical and numerical results can match each other. This means that the same people, or people that have identical qualities must be included in the study to promote continuity. Those who have identical qualities may have to replace those apart of the quantitative study for the simple fact that some may not be available and the study would be most accurate if the data collected is the same, or close to the one collected in the quantitative study. The study will take place over the course of a month so those participating must have availability on the two scheduled examination days. Absence of a single subject can alter results and decrease the authenticity of the study.
Data Collection: The data collected will align with the information gathered from the quantitative study because it is the same study, the only difference is that the information is being reported in terms of qualitative traits not quantitative traits like numbers and percentages. The data collection will take place two days during each week of the month. There will be a total of eight examination days where the researchers communicate with subjects and receive updates on their health and activities in their daily lives. This aspect of the study is important because it is the core of the research and it will determine whether the hypothesis is correct or incorrect. It will also have a social effect where if the coffee is an effective protective agent it will make a difference with those suffering with chronic hepatitis B. The data collected must be accurate and overseen by all of the scientist involved in the study. If the information collected is inaccurate it will completely ruin the research and the study, wasting money and time.
Data Analysis: The data analysis will act as a miniature version of the scientific report. It will analyse all of the information collected throughout the study by various contributors and make cohesive sense of the figures gathered. The data analysis will transform the data collected into legible figures that can easily be translated into a narrative in the form of a report. This aspect crucial in view of the fact that the information received by the public and other members of the scientific and academic community will be through the form of words. The numerical figures will only acts a support for the foundation of the research, the data collected and the words forumalted will make the decision whether the research done was accurate or just another scientific assumption. Even though the contributors apart of the study are always professionals who are aware of bias and confounding factors and the extra measures that have to be taken during scientific research there is still a possibility of human error to occur. Sometimes the error is on the side of the research scientist and sometimes the subjects involved are responsible. Regardless of where the possible error can be coming from, it is important for the authors of the research to implement measures to decrease the possibility. If error occurs, it should be included in the analysis so that the reader can be aware of it as well. An example of this would be if a research study were conducting a new formula of a lipstick. With this new formula palm oil is infused to promote long lasting moisture. An error that one who is collecting data may not be able to control is the time of year, like the summer. During the summer people sweat, so when women are wearing makeup it tends to swell and sweat, making it not last as long as it would during the fall and winter. If one of the subjects where to come in an report that the new formula of lipstick was not as long lasting as the original formula, that would be due to the fact that the summer heat causes makeup to not last as long and that when the subject was using the original formula it was during the winter. That is an error that the researcher cannot control because of the weather. An extra measure that can be taken to prevent this from happening is that the researcher can have one group using the original formula and the other group using the palm oil infused. That will prevent that nature of error from happening and will display the new formula up against the original one having the same conditions without bias. This is the same for the coffee and hepatitis B experiment. External factors that could affect the study will be considered before the start of it so that rules and regulations can be created around it. Preparing for errors decreases their chance of happening. The data analysis of the qualitative study will show the same numerical results of the quantitative study but will express it in non-numerical ways. This is important because the quantitative information will be easier for the public to interpret for the own lives and validity of the research. The data analysis fundamentally summarises the data.
Ethical Issues: The matter of whether the study is ethical or unethical is not a major concern for the coffee and hepatitis B study because coffee is not a controversial topic or substance, it is a regular beverage that is apart of popular culture and is acceptable to drink, especially amongst adults who are the focus of the research being conducted. It is not like a study that employs subjects to smoke marijuana to uncover the effects of medical marijuana on a disease. This can be viewed as unethical because marijuana is undeniably a drug and having subjects take drugs for a study can be seen as dismissing the dangerous effects of the drug and making it acceptable for varying circumstances like scientific research. In the case of the coffee and hepatocellular carcinoma protective agent connections there is no real ethical dilemma unless you are opposed to consuming coffee due to personal beliefs or religious beliefs. In the Mormon faith followers are not allowed to drink coffee so possibly this study could pose a moral threat to a Mormon. This fact should be taken into consideration when forming a sampling group, but in reality, someone who is opposed to consuming coffee will not volunteer to be apart of a study that instructs subjects to drink it. Other than that it is a mild study and does not employ many ethical roadblocks.