BME100 f2014:Group17 L3

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BME 100 Fall 2014 Home
Lab Write-Up 1 | Lab Write-Up 2 | Lab Write-Up 3
Lab Write-Up 4 | Lab Write-Up 5 | Lab Write-Up 6
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Name: Maribel Hernandez
Name: Lauren Britton
Name: Nermin Elsharawy
Name: Aron Lopez
Name: Measho Habtemichael
Name: Talal Alzouman


Descriptive Statistics

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Tables summarizing the mean, standard deviation, and standard error when comparing temperature in degrees Farenheit between the Spree and the thermometer (gold standard).

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Tables summarizing the mean, standard deviation, and standard error when comparing heartbeats per minute (bpm) between the Spree and the gold standard.


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A T-test was used to examine the average (mean) values for the heart rates taken during the walk. The two variables analyzed were the gold standard and the spree heart rates in beats per minute (bpm). The p-value generated from the t-test was 0.8571, which is greater than 0.05. This indicates that there is no significant difference between the gold standard heart rate and the Spree heart rate. However, it was noted that during several readings, the Spree's readings differed from that of the gold standard. It should be noted that the average displayed in the t-test chart will be slightly different than those in the results and descriptive statistics section due to the omitting of certain data due to no recorded Spree readings. The Pearson's r value indicates a decent relationship between the two variables (0.85) however a correlation greater than 0.9 is preferred.


In this lab the Spree was tested against a pulse ox and an oral thermometer to identify its accuracy. At first the spree failed to read pulse until the subject was changed. Once the subject was changed, it began reading the pulse. It was clear then that the Spree does not work for every one. Comparisons couldn’t really be made in between the spree and the oral thermometer since the spree shows body temperature by three colors: blue, yellow, and red. Once the subject became more active or body temperature began to rise, the readings in between the Spree and the pulse ox began to differ.

Before even testing the Spree, one big flaw was clear. There is no way to accurately find body temperature if it is not inside the actual body. In order for the spree to actually measure precisely, it must find a way to test from the inside of the body rather than just the surface of the skin, which can be affected by climate. Another thing that would help its accuracy would be to have accurate readings when the subject’s pulse began to rise so there won’t be so much error when compared to the pulse ox. It would be more helpful to make the Spree more sensitive in order to pick up readings with everyone that attempts to use it. As can be seen in the graphs, the Spree is much more accurate in recording heart rate than temperature as the standard deviation is much greater in the Spree when compared to the thermometer. The standard deviations are much more similar when comparing the heart rate data between the Spree and the gold standard device, indicating the Spree is more accurate at measuring heart rate than temperature. This indicates that there is room for improvement in the design.


Target Population and Need

The target population would be people who work out and maintain an active lifestyle or those who want to become active and improve their lifestyle. People with heart problems that need to monitor their heart rates would be excellent candidates for this device. Common heart conditions such as diabetes or high blood pressure can be easily monitored with the wristband.

Device Design

The device will be in a black wristband form with a neon green accent to improve visibility. The band will have direct contact to the person's wrist and improve better pulse readings. Since the band has direct contact to the skin, their would be improved temperature readings that would be fairly close to an oral temperature reading. The wristband is better than the spree because it is easier to wear and would not leave headlines on the customer. Unlike the spree, the wristband would feature a screen that would provide heart rate and temperature readings without the need of a smart phone. In order to keep the wristband secure on the wrist, the product will have a clamp like design that will adjust to most people's size. The rubberized finish to this wristband would provide a weather and water resident feature.There is also an option to log data from the wristband to a smartphone via bluetooth by using an app to save the data day by day. In the case that the person's heart rate should go below or above the average, there will be a small beeping noise to notify the user. A flashing warning message will appear on the screen if the heart rate or temperature have a drastic change. This device will be light weight and about half an inch wide.

Inferential Statistics

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T-tests were performed on the Easy Monitor and compared to the gold standard, a finger pulse oximeter. The Pearson's coefficient was above 0.9 in all three trials, indicating there is a strong relationship between the new product and the gold standard, this is much higher correlation than found in a competing product, the Spree forehead monitor. This may be projected onto the population as a whole, one may infer that this would be more successful and accurate at monitoring the overall population than the Spree, which did not work on some customers and had less accurate readings, indicating the new product may be a more desirable choice.


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