BME100 f2015:Group7 8amL3

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BME 100 Fall 2015 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: Andrew Medina
Name: Farah Al Yasari
Name: Rafael Lopez
Name: Kelly Harper
Name: Tristan Loveday
Name: Jeremy Atkinson


Descriptive Statistics



    Standard Deviation: 1.193736
    Standard Error: 0.061809

Thermometer (Gold Standard)

    Standard Deviation:1.020886868
    Standard Error: .052859518

T-Test: 7.93663e-60

Pearson's R: .087158866

Heart Rate-


    Average: 96.7942
    Standard Deviation: 23.45037
    Standard Error: 1.262525

Pulse-ox (Gold Standard)

    Average: 95.82029
    Standard Deviation:23.00208
    Standard Error: 1.23839

T-Test: 0.102593

Pearson's R: 0.88692



Heart Rate:


Heart Rate Analysis:

Because the t-test for the heart rate values was greater than 0.05 (5% confidence interval) at approximately 0.103, the heart rate data from the pulse ox and the spree headband were not statistically different. This indicates that the spree headband was indeed recording accurate data of heart rate. If the headband’s data was statistically different, that would indicate that the headband was recording information that was different that the gold standard. The headband would therefore be considered less precise. The Pearson value for the spree and pulse ox data was approximately 0.887. As this number is close to 1, it indicates a strong, although not perfect, positive correlation between the data sets. This means that the spree headband, while not recording identical information to the pulse ox, did give similar heart rate readings. The spree headband therefore appears to be a good measure of heartrate, although it is not completely accurate.

Temperature Analysis:

The t-test value for temperature was incredibly small (approximately 7.937*10^-60), meaning that the values for the spree headband and the thermometer where statistically different. The spree headband is therefore not precise, as its readouts were different from the accepted gold standard of the thermometer. The Pearson’s R value for the spree and the thermometer data was approximately 0.087. Although it is positive, indicating a positive correlation, the correlation is very weak. If the spree headband accurately recorded body temperature, there would have been a strong correlation, with an R value approaching one.

Summery (Design Flaws) – Spree Headband:

The Spree Fitness Heart Monitor makes various and exciting promises. The company advertised that “Spree provides a pinpoint accurate reading of your body temperature throughout your workout to find your optimal body temperature zones for warm up, workout, and cool down” – while this sounds great in theory, the data refutes it. The spree does not provide detailed measurement of body temperature, it shows a scale of four colors that guesstimate temperature. On top of that, the scale does not register the temperature precisely. For the first two measurements the spree recorded the temperature to be one out of four, and for the next twenty-three measurements, the temperature read two out four. This seems to be inaccurate since the subject engaged in activities such as running up the stairs, speed walking in the heat, and consuming calories. This suggests that the headband fails to collect accurate and specific measurements, and it requires a great amount of change to push up the temperature scale. It is not as useful and efficient as advertised in measuring the body temperature. It is recommended that the company implements a specific body temperature reader instead of a scale by utilizing more advanced technology. The company continues to advertise the Spree Heart Monitor. Their ad claims that “Using a plethysmograph, Spree measures heart rate with a non-visible light that views the change in the size of blood vessels through the skin. This gives an accurate measure of heart rate in beats per minute”. The spree had the correct units; and specific plus precise measurement. Also, the device recorded an increase in heart rate when the subject was active. The Spree is easy to use and has a comfortable size, but it is not aesthetically pleasing and it encourages sweat around the headband. The subjected reported that it felt unappealing to wear a band around the forehead and it is concerning that touching the sensors may mess up the results. It is recommended that the company collaborates on the design, so it does not look as if the person is wearing an elastic band around their forehead. Also, different material may be used to prevent excess sweating. In conclusion. The Spree Fitness Heart Monitor is overpriced, overrated, and may be easily replaced, but it has the potential if effort is made to improve it.


Target Population and Need

1. The target population for our device is anyone who plays a sport that is at risk for suffering a concussion. Certain sports, especially contact sports, give athletes a high chance for developing a concussion through repeated, high force impacts that can cause brain injury. These sports include football, soccer, hockey, and others. 2. This target population could use a device that can accurately assess the risk that the wearer has sustained a concussion. The problem in many sports is that athletes will develop a concussion from a high force collision, and then either not realize it or stay in the game regardless. Often athletes may choose to remain in the game to improve their chances of making the team, or the team’s chances of winning. In doing so they risk further damaging their brains and suffering serious health complications. Our device will measure changes in acceleration, and send this data wirelessly to trainers on the sideline during games or practice. If players register collisions of a high enough change in acceleration, they will be flagged by the device for a potential concussion. The device will also measure brain swelling via tympanometry (measuring vibrations in the middle ear). If swelling is recorded, they player will be flagged by the device. This two sided approach will make it much less likely that a concussion occurs unnoticed, improving diagnosis of sports related concussions.

Device Design

Inferential Statistics


Accelerometer (Golden Standard)

    count: 20
    standard deviation:4.027537
    standard error:0.900585


    count: 20
    average: 49.05
    standard deviation: 4.211201
    standard error: 0.41653

t-test: 0.329877

pearson's r: 0.964145


Tympanometer (Gold Standard

    count: 20
    average: 4.26
    standard deviation: 0.114248
    standard error: 0.025547


    count: 20
    average: 4.265
    standard deviation: 0.138697
    standard error: 0.031014

t-test: 0.748137

pearson's r: 0.870225


Brainsaver is 1, golden standard is 2.