BME100 f2015:Group8 1030amL1
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LAB 1 WRITE-UP
Independent and Dependent Variables
The independent variable in this experiment will be the amount in milligrams of lipopolysaccharide given to each of the five groups. Lipopolysaccharide is the independent variable because it is the drug that is being varied to measure the amount of inflammation in this experiment
The dependent variable in this experiment will be the levels of the protein Inflammotin in the blood stream of the test subjects. The level of inflammation is being measured and therefore depends on the amount of the Lipopolysaccharide being taken.
A double-blind experiment is conducted to measure the protein Inflammation level of each subject before and after a dose of lipopolysaccharide is administered.
Each group is administered a different level of lipopolysaccharide: 0 mg, 2.5 mg, 5.0 mg, 7.5 mg, and 10 mg. These increasing levels of the drug allow a determination of the lowest range at which the drug functions.
A total sample of 100 elders between the ages of 65-85, randomly selected from the Social Security data base, are split into 5 groups. This age range allows a wide variety of subjects and includes subjects who are elderly but are healthy and strong enough to withstand the drug. Each of the 5 groups contains 20 people, consisting of 5 elders from the ages of 65-70, 5 of 70-75, 5 of 75-80, and 5 of 80-85. Specific age ranges are implemented in order to decrease biases in the sample (for example, if one group were all 80+). The elders of each age group are then randomly placed into groups.
Two groups of 20 elders act as controls; one group of 20 is given a placebo which contains no drug, and another group is given the highest dosage of the drug at 10 mg, to validate that the drug will have taken effect and to compare the two extremes of the drug. Of the three remaining groups, one is given a dosage of 2.5 mg, the second 5.0 mg, and the third 7.5 mg. Each member of all the groups is tested for inflammation levels before taking the drug. Then, after taking the drug, each member of each group is tested four times: 30 minutes, 60 minutes, 90 minutes and 120 minutes after taking the drug. The subjects are tested every day for a week and each group will take the same dosage as they did before, in order to repeat the test and minimize error.
During each test, neither the experimenter nor the subject will know what dosage they are administering/given, so that there is no placebo effect or observer-expectancy effect. This reduces bias and error in the experiment.
There are five groups, with the following amounts of lipopolysaccharide given to each group of subjects: 0 mg, 2.5 mg, 5 mg, 7.5 mg, and 10 mg. 5 groups were chosen in order to give a certain level of accuracy in determining the lowest amount of the drug needed to cause inflammation. The two extreme groups (0 mg and 10 mg) act as controls for the experiment, with 0 mg acting as a control to verify that no other variables within the experiment are causing inflammation, and with 10 mg acting as a control for the drug's performance. The middle three groups act as a net to determine the lowest amount at which the drug performs, giving a range of 2.5 mg for each category. For example, if increased inflammation is recorded in the group given 2.5 mg, then it would follow that the drug's lowest dose of performance is somewhere in the range of 0-2.5 mg.
A twenty-year age range of 65-85 was chosen. The rationale for choosing the subjects is to have a definite age range for the “elderly” as defined in the study. The ages 65-85 set a lower range of what could start to be defined as elderly and 85 is the upper range while still including relatively healthy subjects.
There are 20 subjects in every group. Each group has five people in the following age ranges: 65-70, 70-75, 75-80, and 80-85. The rationale for picking these age groups is to have an evenly distributed sample group for the study. Taking one person from each age between 65 and 85 allows the study to show the effects of lipopolysaccharide in a large age range while keeping the group small enough for monetary reasons.
Subjects are citizens on the Social Security list
Subjects must fit into age range listed (65-85) Reason: Subjects are chosen out of the Social Security list because it contains a large part of the population of the elderly, reducing the risk of limiting the sample size to a small population, which could increase bias within the experiment. The specific age-range chosen gives a large range of people to choose from (again, reducing bias in the samples), but also limits the samples to the elderly that are most likely in good enough health so that other confounding variables (such as age-related diseases) do not put the experiment or the people at risk. Subjects are randomly selected based on their social security number.
Subjects show prior inflammation
Subjects use medicine that affects Lipopolysaccharide. Reason: These exclusion criteria were included in order to reduce the possibility of bias and confounding variables (such as other drugs or diseases which could alter the results of the experiment).
Sources of Error and Bias
Sources of Error in the experiment may include other health problems that each individual may have, such as allergies or certain medical conditions that may impact the blood results. Another source of error in this experiment may include other medicines or treatments that each of the subjects is currently taking that could potentially impact the protein levels in the test subjects' blood system. Since the sample population only includes people of the age 65 to 85 who are registered with the Social Security Administration in the United States, another source of error may be created by not including people who are not registered with the Social Security Administration. Therefore this experiment does not measure subjects from outside the United States, which may create different results had this experiment been conducted on the global scale.