BME100 f2014:Group25 L1

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LAB 1: The Effect of Lipopolysaccharide on Inflammotin Levels in the Elderly

Independent and Dependent Variables

The Independent Variable is the dosage of the Anti-inflammatory, Lipopolysaccharide, because that is the variable being manipulated by the experimenter. The Dependent Variable is the amount of inflammatory protein, Inflammotin, found in the elderly because they are dependent on the amount of Lipopolysaccharide administered to the patients. In other words, the concentration of Inflammotin measured in the bloodstream changes relative to the amount of LPS taken by the test subjects.

Experimental Design

In this experiment, elderly people will be randomly selected and assigned into four groups of ten. The control group's participants must have zero exposure to any other medications within the last two weeks. The other three groups will not be surveyed or tested for prior exposure to drugs. First, each participant will be tested and screened for lipopolysaccharide allergies and any inabilities to produce Inflammotin to assure accurate results in the data set. After this screening, a blood test will be administered to measure initial levels of Inflammotin (no LPS will be in their system). Then, each group will take their respective LPS dosage: 0mg, 5mg, 8mg, or 10mg. Then another blood test will be taken to track Inflammotin levels over time. This procedure will be repeated three times during this experiment.

After all of the quantitative data is collected, qualitative data (e.g. age, race, gender, health conditions, drugs currently taking) will be collected to be taken into account upon running statistical analyses with ANOVA for multivariance. Moreover, Pearson's R Correlation test will be run to determine which dosage is the most effective at producing Inflammotin, while still being cost-effective.

There will be four groups containing ten elderly participants each, with the participants randomly assigned into one of the groups. One group will be the control group, in which a placebo will be n administered in lieu of the drug. The following three groups will be given dosages of five, eight, and ten milligrams, respectively. The drug will be taken three times over the course of the experiment, with a blood test before and after each administration. The Inflammotin levels over the course of the trial will be measured and recorded to analyze its change over time relative to the amount of LPS administered to each patient.

All of the test subjects will be between the ages of 65-85 in order to have a normalized elderly sample. LPS has been found to have a greater effect on the elderly. Subjects outside of this age group may not provide statistically significant results, and will therefore not be included.

Number of subjects per group
Ten people between the ages of 65-85 will be analyzed in each of the four groups to provide a proper amount of data for significant testing.

The control group will consist of a ten elderly individuals that have not been taking prior medication. A placebo drug will be administered to this group without its, nor the administer’s, knowledge on what drug and what dosage -- if any -- is being administered. The placebo is used in order to prevent error and bias. The results of this group will be used as a baseline in order to see the effect of the drug on the other three experimental groups.

Subject Selection

Elderly between the ages of 65-85 will be tested in this experiment in efforts to find the effect of the LPS on Inflammotin levels in the bloodstream. Younger people are excluded because they will not contribute any significant results since the emphasis of this study is geared towards the health of the elderly. The upper boundary of 85 was used because most people over 85 years of age are more prone to sickness and disease, which would may compromise the data.

Since this experiment is run on a budget, randomly selected volunteers will be used and placed into three random groups of ten. The fourth group, the control group, will consist of ten randomly selected elderly people who have not been regularly taking any medications to ensure that there is no external source of error in their blood test results when measuring LPS vs. Inflammotin levels.

This will increase the cost-effectiveness of the experiment, reduce the bias, and provide a wide range of test subjects that qualify under the subject selection criteria.

  • Prior to the experiment, all patients must undergo an allergy screening to assure that no unintentional harm will be done during experimentation with the lipopolysaccharide. This will increase the accuracy of the data set and maintain equal sample sizes.*

Sources of Error and Bias

This experiment will be double-blinded and therefore leaves a small margin for bias from both the experimenters and the participants. Furthermore, the participants are randomly selected and assigned into groups, reducing the chance that any participant or experimenter will have any tacit knowledge on the study. By performing a double-blinded experiment, neither the subject nor the experimenter will have have preconceived misconceptions or notions on the study, or expected results -- which ultimately will give them no incentive to manipulate the results.

Given the age range of the test subjects, it is likely that they will already be taking a wide variety of medication. Testing the drug on subjects that are already under the effects of other medications would be testing multiple variables (the effect of the anti-inflammatory on a person while under drug X as well) which would be considered a source of error. The control for this source of error is the placebo group.

Moreover, there was failure to perform sample size analysis (statistical power analysis) before the study took place. Although it is important to know how many subjects are needed to achieve the minimum power level desired, ten is stated sample size large enough to calculate averages and statistical analyses within a small community (Refer to: [1]).

Furthermore, another source of error is that the drug dosage increments are not equal and may not show evident signs of the effect of lipopolysaccharide on Inflammotin levels. To control this possible source of error, an ANOVA test will be run, along with Pearson's R Correlation test to verify which dosage is most effective at producing Inflammotin.