Analysis Force Plate Measurements
George Heintz
“https://rpubs.com/jheintz/762531”
Configuration
\[\newcommand{\eq}[1]{\begin{align*}#1\end{align*}}\]
Preprocessing
Data Sets Steadyness.measures and Fequency Spectral Density
| Trial | AP_ | ML_ | RDIST.AP | RDIST.ML | MDIST | RDIST | TOTEX | TOTEX.AP | TOTEX.ML | MVELO | MVELO.AP | MVELO.ML | AREA_CC | AREA_CE | MFREQ | POWER | POWER.ML | POWER.AP |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| BDS00001 | -7.994 | 0.949 | 0.300 | 0.173 | 0.308 | 0.346 | 29.924 | 27.872 | 7.565 | 0.611 | 0.569 | 0.154 | 1.011 | 0.968 | 0.315 | 1.237 | 0.339 | 3.551 |
| BDS00002 | -7.734 | 0.550 | 0.383 | 0.157 | 0.335 | 0.414 | 32.398 | 29.909 | 8.562 | 0.661 | 0.610 | 0.175 | 1.697 | 1.131 | 0.314 | 2.434 | 0.731 | 7.103 |
| BDS00003 | -7.890 | 0.417 | 0.208 | 0.125 | 0.216 | 0.242 | 27.971 | 26.232 | 7.064 | 0.571 | 0.535 | 0.144 | 0.498 | 0.486 | 0.421 | 0.579 | 0.429 | 1.517 |
| Trial | Freq | RD.dens | AP.dens | ML.dens |
|---|---|---|---|---|
| BDS00001 | 0.04 | 14.64 | 14.76 | 12.28 |
| BDS00001 | 0.06 | 7.00 | 82.38 | 1.65 |
| BDS00001 | 0.08 | 7.95 | 9.39 | 2.24 |
| BDS00001 | 0.10 | 2.40 | 71.72 | 0.25 |
| BDS00001 | 0.12 | 6.21 | 9.85 | 0.13 |
Merging data with BDSInfo
## 'data.frame': 1930 obs. of 31 variables:
## $ Trial : chr "BDS00001" "BDS00002" "BDS00003" "BDS00004" ...
## $ Subject : num 1 1 1 1 1 1 1 1 1 1 ...
## $ Vision : chr "Open" "Open" "Open" "Closed" ...
## $ Surface : chr "Firm" "Firm" "Firm" "Firm" ...
## $ AgeGroup : chr "Young" "Young" "Young" "Young" ...
## $ Age : num 33 33 33 33 33 33 33 33 33 33 ...
## $ Illness : chr "Yes" "Yes" "Yes" "Yes" ...
## $ Illness2 : chr "Hypothyroidism" "Hypothyroidism" "Hypothyroidism" "Hypothyroidism" ...
## $ Disability : chr "No" "No" "No" "No" ...
## $ Disability2: chr "No" "No" "No" "No" ...
## $ Footwear : chr "Flip-Flops" "Flip-Flops" "Flip-Flops" "Flip-Flops" ...
## $ BMI : num 21.8 21.8 21.8 21.8 21.8 ...
## $ AP_ : num -7.99 -7.73 -7.89 -6.89 -7.69 ...
## $ ML_ : num 0.949 0.55 0.417 0.567 0.58 ...
## $ RDIST.AP : num 0.3 0.383 0.208 0.181 0.419 ...
## $ RDIST.ML : num 0.173 0.157 0.125 0.1 0.205 ...
## $ MDIST : num 0.308 0.335 0.216 0.18 0.41 ...
## $ RDIST : num 0.346 0.414 0.242 0.207 0.466 ...
## $ TOTEX : num 29.9 32.4 28 26.4 30.6 ...
## $ TOTEX.AP : num 27.9 29.9 26.2 24.4 28.6 ...
## $ TOTEX.ML : num 7.57 8.56 7.06 7.21 7.59 ...
## $ MVELO : num 0.611 0.661 0.571 0.539 0.624 ...
## $ MVELO.AP : num 0.569 0.61 0.535 0.498 0.583 ...
## $ MVELO.ML : num 0.154 0.175 0.144 0.147 0.155 ...
## $ AREA_CC : num 1.011 1.697 0.498 0.38 1.892 ...
## $ AREA_CE : num 0.968 1.131 0.486 0.337 1.61 ...
## $ MFREQ : num 0.315 0.314 0.421 0.476 0.242 ...
## $ POWER : num 1.237 2.434 0.579 0.533 1.869 ...
## $ POWER.ML : num 0.339 0.731 0.429 0.33 0.568 ...
## $ POWER.AP : num 3.55 7.1 1.52 1.6 6.06 ...
## $ BMI.Class : Factor w/ 3 levels "normal","overweight",..: 1 1 1 1 1 1 1 1 1 1 ...Analysis
Surface: firm vs. foam
vision eyes closed, young, no illness 
Observations: The mean velocity from and to the COP, considering total excursion. The mean velocity is higher on soft than on firm base of support. On the firm surface it looks like 3 modes at 0.6, 1, and 1.9 MVELO. The MVELO distribution on foam base of support is skewed the right.
Age: young vs. old
- Vision eyes closed, surface firm
- Vision eyes closed, surface foam
p-value = 0.01584 for surface = firm
p-value = 8.911e-08 for surface = foam
Observation: Higher average velocity is observed for older population on a firm and foam base of support. The velocity distribution of both population is skewed the right. 1. upper plot: firm, eyes closed Shows 2 modes at .6 and at 1. 2. lower plot: foam, eyes, closed Shows mode.
Vision: eyes open vs closed
- young, no illness, firm surface
- old, with illness, firm surface
1. Upper Plot and Test:
Plot shows eyes open vs eyes closed for young population on a firm base with no illness. The average velocity is higher with eyes closed. The p-value indicates statistical significance.
2. Lower Plot and Test:
Plot shows eyes open vs eyes closed for old population on a firm base with illness (sample size restriction). The average velocity is higher with eyes closed. The p-value indicates statistical significance.
Observation: The effect of higher average velocity when eyes are closed seems to increase with age. The point estimate difference of -0.0874 (young population) is about 22% smaller than -0.1113 (older population). The analysis was not controlled for disease.
Analysing Disease Influence
Disease Overview Cases
Using regular expression the following diseases have been selected from Illness2 and Disability2.
| Counts | Illness.Disability |
|---|---|
| 336 | Hypertension |
| 138 | Diabetes |
| 138 | Arthrosis |
| 132 | Rhinitis |
| 129 | Osteoporosis |
| 102 | Hearing |
| 84 | knees |
| 72 | Spine |
| 48 | Depression.Anxiety |
| 40 | Visual |
| 36 | Tendinitis |
| 36 | Hyperthyroidism |
| 24 | Heel |
| 21 | Cerebral_Palsy |
| 12 | Parkinsons |
Hypertension
Description:
People with high blood pressure and or heart problems can feel light headed and may have a different stabilogram profile. The test should show the statistical significance of this hypothesis.
Testing: MVELO | firm surface, eyes open
Remark: There is not difference MVELO when hypertension is present or missing. This counts also for POWER, frequency density.
Spine
Conditions: firm, open, sample size 72
Heel
Sever’s disease is a painful condition of the heel that occurs in growing children. It happens when the tendon that attaches to the back of the heel (the Achilles tendon) pulls on the growth plate (the apophysis) of the bone of the heel (the calcaneus).
Conditions: firm, open sample size = 24
Arthrosis
Description:
1. 4 x hypothesis test arthrosis yes/no for eyes open, closed and surface firm and foam
2. all signficant
Diabetes
Conditions: firm, open
BMI (not finished! test conditions to be developed…)
Upper Plot and Test: obese & overweight vs. normal | shows eyes open, all ages, firm, no illness, no disability (obese fall out) The average velocity is higher with larger with higher BMI. The p-value indicates statistical significance. The obsese density curve shows two modes, which may be caused by age.
Lower Plot and Test: MVELO ~ obese & overweight vs normal | firm, eyes open, A average velocity is for high BMI with eyes open, firm surface, illness and disabilty.
Plot shows eyes open vs eyes closed for old population on a firm base with illness (sample size restriction). The average velocity is higher with eyes closed. The p-value indicates statistical significance.
- Test MVELO ~ illness yes, no | obese, overweight, eyes open, surface firm A higher average velocity is observed for obese and overweight with illness.
Observation: The effect of higher average velocity when eyes are closed seems to increase with age. The point estimate difference of -0.0874 (young population) is about 22% smaller than -0.1113 (older population). The analysis was not controlled for disease.
Analysing Footwear Influence
Flip Flops vs. all other
Conditions: Foam, eyes open
Remark: If surface is firm, no statistical signficant difference.
Flip Flops vs. Casual shoes
Conditions: foam, open, young, no illness sample size = 18
Clustering (k-means)
Descriptive Statistics on Illnes, Disability, BMI
| Disability | Disability2 | n |
|---|---|---|
| No | No | 1761 |
| Yes | Hearing (Left ear and Right ear) | 18 |
| Yes | Hearing (Left ear and Right ear), Visual (Right eye) | 12 |
| Yes | Hearing (Left ear) | 36 |
| Yes | Hearing (Right ear) | 36 |
| Yes | Intellectual | 12 |
| Yes | Physical (Cerebral Palsy) | 21 |
| Yes | Physical (Poliomyelitis) | 6 |
| Yes | Visual (Left eye and Right eye) | 12 |
| Yes | Visual (Left eye and Right eye), Physical (Tumor in the head surgery) | 4 |
| Yes | Visual (Left eye) | 12 |
Illness
| Illness2 | Illness | n |
|---|---|---|
| Allergy | Yes | 12 |
| Allergy, Osteoporosis, Conjunctivitis | Yes | 12 |
| Anemia, Hypertension, Spine problem | Yes | 12 |
| Anxiety | Yes | 12 |
| Arrhythmia, Arthrosis | Yes | 12 |
| Arrhythmia, Hypertension | Yes | 12 |
| Arthrosis | Yes | 24 |
| Arthrosis of the knees | Yes | 12 |
| Arthrosis of the spine/knees/toes | Yes | 12 |
| Ascending colon cancer, Progressive breast cancer | Yes | 12 |
| Asthma | Yes | 60 |
| Asthma, Dermatitis, Keratoconus | Yes | 12 |
| Asthma, Hypertension | Yes | 12 |
| Chodromalacia of the knees | Yes | 12 |
| Deep vein thrombosis | Yes | 12 |
| Depression, Arthrosis of the left knee, Labyrinthitis | Yes | 12 |
| Depression, Hypercholesterolemia, Arthrosis | Yes | 12 |
| Diabetes mellitus | Yes | 48 |
| Diabetes mellitus, Arthrosis of the feet/hands, Vascular leakage of the eyes | Yes | 12 |
| Diabetes mellitus, Hypertension | Yes | 12 |
| Diabetes mellitus, Hypertension, Osteoporosis, Arthrosis | Yes | 12 |
| Diabetes mellitus, Hypothyroidism, Hypercholesterolemia, Osteopenia | Yes | 12 |
| Diabetes mellitus, Osteopenia, Labyrinthitis | Yes | 12 |
| Diabetes mellitus, Osteoporosis | Yes | 12 |
| Endometriosis | Yes | 24 |
| Familial Hypercholesterolemia, Chodromalacia of the knees, Sinusitis, Rhinitis | Yes | 12 |
| Hashimoto disease, Rhinitis | Yes | 12 |
| Heart disease, Lymphedema of the lower members | Yes | 12 |
| Heel spurs, Heart problem, Arthrosis of the hands | Yes | 12 |
| Heel spurs, Inflammation of the tibial nerve, Prostatitis, Skin cancer | Yes | 12 |
| Hepatitis B | Yes | 12 |
| Herniated lumbar of the L4-L5 discs | Yes | 12 |
| Hypercholesterolemia | Yes | 48 |
| Hypercholesterolemia, Osteopenia | Yes | 24 |
| Hypertension | Yes | 60 |
| Hypertension, Diabetes mellitus, Osteopenia, Labyrinthitis, Hypothyroidism | Yes | 12 |
| Hypertension, Diabetes mellitus, Poliomyelitis | Yes | 6 |
| Hypertension, Heart problem | Yes | 12 |
| Hypertension, Hypercholesterolemia, Essential tremor, Osteopenia, Gastritis, Esophagitis | Yes | 12 |
| Hypertension, Hypercholesterolemia, Glaucoma, Arthrosis | Yes | 6 |
| Hypertension, Hypercholesterolemia, Labyrinthitis, Asthma, Varicose veins of the legs | Yes | 12 |
| Hypertension, Hypercholesterolemia, Osteopenia | Yes | 12 |
| Hypertension, Hypercholesterolemia, Osteopenia, Arthritis, Bursitis | Yes | 12 |
| Hypertension, Labyrinthitis | Yes | 12 |
| Hypertension, Labyrinthitis, Prostate disease, Skin disease | Yes | 12 |
| Hypertension, Lumbar tumor, Osteoporosis | Yes | 12 |
| Hypertension, Migraine | Yes | 12 |
| Hypertension, Osteopenia, Arthritis, Sinusitis | Yes | 12 |
| Hypertension, Osteoporosis, Herniated lumbar disc, Labyrinthitis | Yes | 12 |
| Hyperthyroidism | Yes | 12 |
| Hyperthyroidism, Tendinitis of the knees | Yes | 12 |
| Hypoglycemia | Yes | 24 |
| Hypothyroidism | Yes | 36 |
| Hypothyroidism, Breathlessness | Yes | 12 |
| Hypothyroidism, Hypercholesterolemia, Hypertriglyceridemia, Osteopenia, Fatty liver | Yes | 12 |
| Hypothyroidism, Hypertension | Yes | 12 |
| Hypothyroidism, Hypertension, Hypercholesterolemia | Yes | 12 |
| Hypothyroidism, Rheumatism, Anxiety, Osteopenia, Gastroesophageal reflux | Yes | 12 |
| Hypothyroidism, Rhinitis | Yes | 12 |
| Intestine disorder | Yes | 12 |
| Labyrinthitis | No | 12 |
| Labyrinthitis | Yes | 24 |
| Labyrinthitis, Hypertension, Hypercholesterolemia | Yes | 12 |
| Labyrinthitis, Osteoporosis, Hypothyroidism | Yes | 9 |
| Melanoma | Yes | 12 |
| No | No | 661 |
| Osteeopenia | Yes | 12 |
| Osteoporosis | Yes | 12 |
| Osteoporosis, Arthrosis, Hypercholesterolemia, Hypoglycemia | Yes | 12 |
| Osteoporosis, Fibromyalgia | Yes | 12 |
| Osteoporosis, Hypertension, Hyperthyroidism | Yes | 12 |
| Osteoporosis, Osteopenia, Hypothyroidism, Stroke, Hypertension, Hypercholesterolemia, Bronchitis | Yes | 12 |
| Parkinson’s disease | Yes | 12 |
| Rhinitis | Yes | 24 |
| Rhinitis, Migraine | Yes | 12 |
| Rhinitis, Sickle cell anemia | Yes | 12 |
| Rhinitis, Sinusitis | Yes | 24 |
| Rhinitis, Sinusitis, Kidney stones | Yes | 12 |
| Scoliosis, Hypercholesterolemia | Yes | 12 |
| Sjogren’s syndrome | Yes | 12 |
| Tendinitis | Yes | 12 |
| Tendinitis of the knees/feet, Ligament problems, Spine problem, Asthma | Yes | 12 |
| Urinary tract infection, Osteopenia | Yes | 12 |
| Vasovagal syncope, Gastritis, Bronchitis, Rhinitis, Gastroesophageal reflux | Yes | 12 |
| Vitiligo | Yes | 12 |
BMI
| BMI.Class | n |
|---|---|
| normal | 1281 |
| overweight | 589 |
| obese | 60 |
Footwear
| AgeGroup | Footwear | n |
|---|---|---|
| Old | Casual shoes | 276 |
| Old | Casual shoes, Dress shoes | 12 |
| Old | Casual shoes, Flip-Flops | 24 |
| Old | Casual shoes, Sandal | 24 |
| Old | Dress shoes | 48 |
| Old | Flip-Flops | 24 |
| Old | Orthopedic shoes | 12 |
| Old | Sandal | 123 |
| Old | Sandal, Casual shoes | 12 |
| Old | Walking shoes | 142 |
| Old | Walking shoes, Boots | 12 |
| Old | Walking shoes, Casual shoes | 84 |
| Old | Walking shoes, Flip-Flops | 36 |
| Old | Walking shoes, Sandal | 60 |
| Young | Boots | 36 |
| Young | Casual shoes | 72 |
| Young | Flip-Flops | 36 |
| Young | Sandal | 24 |
| Young | Tennis with zero drop | 12 |
| Young | Walking shoes | 681 |
| Young | Walking shoes with silicone insole | 12 |
| Young | Walking shoes, Boots | 12 |
| Young | Walking shoes, Casual shoes | 36 |
| Young | Walking shoes, Flip-Flops | 84 |
| Young | Walking shoes, Flip-Flops, Casual shoes | 12 |
| Young | Walking shoes, Sandal | 24 |
| Disability | Disability2 | n |
|---|---|---|
| No | No | 1761 |
| Yes | Hearing (Left ear and Right ear) | 18 |
| Yes | Hearing (Left ear and Right ear), Visual (Right eye) | 12 |
| Yes | Hearing (Left ear) | 36 |
| Yes | Hearing (Right ear) | 36 |
| Yes | Intellectual | 12 |
| Yes | Physical (Cerebral Palsy) | 21 |
| Yes | Physical (Poliomyelitis) | 6 |
| Yes | Visual (Left eye and Right eye) | 12 |
| Yes | Visual (Left eye and Right eye), Physical (Tumor in the head surgery) | 4 |
| Yes | Visual (Left eye) | 12 |