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Re: BFS Survey

PostPosted: May 11th, 2011, 10:22 am
by pbohan
A quick update, we now have 31 participants. In general, the people participating, have not had BFS symptoms very long - under 5 years. I think we are missing people that have had this disorder for long lengths of time and may have tried a lot of different remedies. This information would be vital (actually all information is vital, but people that have tried most remedies would undoubtably be very helpful to find correlation).

Re: BFS Survey

PostPosted: May 12th, 2011, 1:22 pm
by pbohan
Anyone with statistic knowledge, please provide me feedback. My statistic knowledge may have regressed over the years since my retirement so I may be a little rusty. So please correct me if my assumptions/conclusions are wrong or if you have a better way to explain these results. And if you have any suggestions for some future model results from our survey please let me know. In the past, my goal when building a linear regression model was to predict an outcome, so I was more interested in the R² value of the model and not so much for correlation – so I welcome some insight I may be overlooking. My hope here is to try to show what type of information can be generated to get more people involved in the survey. Remember, the sample size is too small to jump to any conclusions. And this is not an official scientific study, but it may shed light on what to study in the future or what we can try to do to alleviate symptoms. Once again, the data columns is not aligned properly when I compied over the results. If someone wants me to send them these excel files so they can be viewed easier, please provide me your email address. My email is [email protected].

Below are a couple of linear regression models based on the data we have to date (31 participants, so n = 31). However, in the models below participant data was eliminated if they answered 0 (have not tried) certain remedies. The first model solves for Benzo drugs to see if there is correlation between symptoms and body part affected by the symptoms. We only have data for 14 people (n=14) that have tried the Benzo drug, this is a very small sample size. First, I ran the model using all symptoms and body parts and by trial and error kept eliminating those parameters that did not correlate. The Benzo model is fairly weak. It has about 41% (Adjusted R²) correlation to the symptoms Pins and Needles, Cramps, Muscle Stiffness, Vibration / Buzzing, and Arms and Shoulders. Another statistic of importance is “t statistic”. Those parameters that have a high absolute value of t statistic have the highest correlation. A t statistic above 2 is best. In this case Cramps (-2.44), Vibration / Buzzing (2.18), and Pins and Needles (2.06) have the best correlation. Hence, a person that tries a Benzo drug has a chance to see some change in the symptoms: Cramps, Vibration / Buzzing, and Pins and Needles; and the body part that may see a change are the arms and shoulders (although that correlation is fairly weak, t-statistic -1.42). The higher the value of F Statistic the better the model, which equates to a lower value of p. A higher t statistic also means a lower value of p. SE is the standard error of the model. In this case, the standard error is 1.99. If for example a person answered that Benzo helped them by a factor of 2 (out of 10 in the survey), it is possible their value in the model may be 2+1.99 or 2-1.99 (3.99 or .01). This is the worst case scenario. This can be shown by the residual error plot that I did not include below. The coefficients are the solution to the model:

Benzo = 3.095 + .5338x(Pins and Needles) - .8296x(cramps) + .5226 (Muscles Stiffness) + .6073x(Vibration / Buzzing) - .6986x (Arms/shoulders)

Hence, if you have tried Benzo, then if we fill your questionnaire results into the above equation for Pins and Needles, cramps, muscle stiffness, vibration/buzzing sensation, and arms shoulders the result should equal your questionnaire response for Benzo within the standard error of 1.99. Those positive coefficients will drive the Benzo value up and those negative coefficients drive the Benzo value down. My assumption is that most people may have had fairly low survey answers to the above parameters for pins and needles, cramps, muscle stiffness, vibration / buzzing, and arms and shoulders.

n 14 (cases excluded: 17 due to missing values)

R2 0.64
Adjusted R2 0.41
SE 1.99

Term Coefficient 95% CI SE t statistic DF p
Intercept 3.095 -0.850 to 7.040 1.7108 1.81 8 0.1080
Pins and Needles 0.5338 -0.0634 to 1.1309 0.25897 2.06 8 0.0732
Cramps -0.8296 -1.6122 to -0.0471 0.33936 -2.44 8 0.0403
Muscle Stiffness 0.5226 -0.1686 to 1.2139 0.29977 1.74 8 0.1194
Vibration / Buzzing Sensation 0.6073 -0.0341 to 1.2486 0.27812 2.18 8 0.0605
Arms / Shoulder -0.6986 -1.8336 to 0.4365 0.49220 -1.42 8 0.1936

Source of variation Sum squares DF Mean square F statistic p
Model 55.29 5 11.06 2.80 0.0947
Residual 31.63 8 3.95
Total 86.92 13

The next model below is for muscle relaxants. This is the strongest model. People taking a muscle relaxant may see a 77% chance of seeing some change on a variety of symptoms over several body parts. Once again, the sample size is very small, only 15 participants have tried muscle relaxants.

n 15 (cases excluded: 16 due to missing values)

R2 0.92
Adjusted R2 0.77
SE 1.1

Term Coefficient 95% CI SE t statistic DF p
Intercept 6.234 2.075 to 10.393 1.6178 3.85 5 0.0120
Muscle Fatigue and Weakness -1.201 -2.126 to -0.276 0.3598 -3.34 5 0.0206
Headaches 0.6397 0.0355 to 1.2438 0.23502 2.72 5 0.0417
Itching 0.9998 -0.1660 to 2.1656 0.45352 2.20 5 0.0786
Muscle Stiffness 0.558 -0.385 to 1.501 0.3668 1.52 5 0.1887
Sensitivity to Temperatures -1.437 -2.459 to -0.415 0.3977 -3.61 5 0.0153
Feet -0.477 -0.759 to -0.196 0.1095 -4.36 5 0.0073
Neck / Head 1.133 0.407 to 1.859 0.2823 4.01 5 0.0102
Hands 0.2661 -0.0567 to 0.5889 0.12556 2.12 5 0.0876
Arms / Shoulder -0.6067 -1.3740 to 0.1607 0.29850 -2.03 5 0.0978

Source of variation Sum squares DF Mean square F statistic p
Model 72.1 9 8.0 6.31 0.0282
Residual 6.3 5 1.3
Total 78.4 14

The final model is for anti convulsant drugs. This model is also fairly strong based on 16 inputs. Itching, Numbness, Feet, and Arms and Shoulders are the symptoms and body parts with the highest correlation.

n 16 (cases excluded: 15 due to missing values)

R2 0.87
Adjusted R2 0.73
SE 1.20

Term Coefficient 95% CI SE t statistic DF p
Intercept -1.188 -4.656 to 2.280 1.4666 -0.81 7 0.4447
Itching -1.149 -2.400 to 0.102 0.5289 -2.17 7 0.0664
Numbness -0.7151 -1.3615 to -0.0687 0.27335 -2.62 7 0.0346
Vibration / Buzzing Sensation 0.3033 -0.1620 to 0.7685 0.19677 1.54 7 0.1672
Muscle Pain / Soreness 0.2795 -0.2622 to 0.8213 0.22910 1.22 7 0.2619
Sensitivity to Temperatures 0.3696 -0.4083 to 1.1475 0.32898 1.12 7 0.2983
Feet 0.3711 -0.0276 to 0.7698 0.16862 2.20 7 0.0636
Upper Leg -0.3152 -0.9837 to 0.3533 0.28270 -1.11 7 0.3017
Arms / Shoulder 0.6515 0.1719 to 1.1310 0.20280 3.21 7 0.0148

Source of variation Sum squares DF Mean square F statistic p
Model 69.82 8 8.73 6.04 0.0142
Residual 10.12 7 1.45
Total 79.94 15

FYI, although the muscle relaxant model had the best correlation, it has the 2nd lowest average of improvement when compared to anti convulsants and benzo drugs. On average, people that have tried these drugs say that benzo helps about 3.6 (out of 10), muscle relaxants 3.4, and anti-convulsants 3.2. And there are a significant amount of respondents that saw no improvement using these drugs. And finally, we do not know what particular drug and dosage levels that people are taking. This could be a follow up study if we can get a sample size of 100 participants or more. There also could be outliers in the results (people’s whose responses fall outside the typical response of the survey population), which could be eliminated from the model results.

Re: BFS Survey update

PostPosted: May 18th, 2011, 10:51 am
by pbohan
We are up to 36 participants. Still too small a sample to draw conclusions.

Re: BFS Survey update

PostPosted: May 20th, 2011, 7:03 pm
by pbohan
Here are some results of a few models I ran on 39 particpants (not enough to draw conclusions):

Those who felt stess/anxiety caused their condition draws strong correlation to cramps, muscle pain and soreness, muscle relaxants, and Benzo. No body part had significant correlation.

Flu shot correlates to suppliments and sleeping pills but no symptom or body part.

Perscription drugs correlates to vibration/buzzing sensation but no body part or remedy.

Sickness correlates to headaches, abdomen, hands, back, muscle relaxants, diet, and massage

Exercise correlates to twitching, cramps, arms and shoulder, but no remedy.

People with a history of muscle issues correlates to chest, abdomen, feet, and lower leg but no symptom or remedy.

spine or back injury correlates to numbness, upper leg, back, and suppliments.

chemicals correlates with numbness, muscle stiffness, vibration and buzzing, feet, suppliments, and sleeping pills.

Those who think something else caused their BFS correlates with headaches, hands, and homeopathic treatments.

this can all change when we get more participants but it may give us an idea why we all have varying symptoms, affected body parts, and respond different to remedies. It could be because what triggers our BFS causes different symptoms and so forth. this does not mean you cannot have symptoms or other body parts affected if you think fore instance, stress caused your condition. I am merely pointing out the few contitions that have the stronges correlation.

Re: BFS Survey Update

PostPosted: May 25th, 2011, 8:47 am
by pbohan
We have 40 participants. How many doctors and neurologist did you see? And what did they do with your file explaining your symptoms and condition? Most likely it is collecting dust in a file drawer. They did not send the information to be analyzed against others with the condition. They did not even compare your notes with others they have seen with the condition. They did nothing with the information. This is an opportunity to get all our information into one file and try to proper analyze the data using statistics. Isn't this the goal of forum to properly define the syndrome and its characteristics and to try to find answers and solutions? Of course, we all have told our story and now it is time to try to find answers so please participate. Thank You.

Re: BFS Survey Update

PostPosted: June 1st, 2011, 8:53 am
by pbohan
We now have 44 participants. My plan of attack will be to run 330 models/simulations as well as 56 statisical summaries. it will take me quite a bit of time to run and sumarize this data. In all likelyhood I will keep the suvery open for a while to maximize our participants before crunching this massive amount of data. Thanks for participating.

Re: BFS Survey Update

PostPosted: June 6th, 2011, 2:41 pm
by pbohan
First, the good news, we are now up to 48 participants. Now for the bad news, somehow the settings got changed and I am unable to save the data file to my computer. I can see the data, but I am unable to hit any of the selections (i.e. file, data,). I cannot access or edit the survey form. I am not sure how this happened, but it must have happened today 6/6. There has only been one person to update information today and not sure if they could change any file settings. I found a way to get around this by using a select all function, but it requires about 30 minutes of editing to get the data into a format I can use. If anyone has any information about google docs that would be helpful, please let me know.

Re: BFS Survey update

PostPosted: June 6th, 2011, 4:04 pm
by pbohan
I cannot figure out what is wrong. Please continue to send in your responses - I can work around the problem. It only seems to affect google .xls files and not .doc files. People can still access and answer the survey - so lets just move forward.

Re: BFS Survey Update

PostPosted: June 13th, 2011, 8:43 am
by pbohan
A quick update - we now have 49 participants. The sample size is becoming significant, but it would be helpful to get more survey results. Thanks for participating.

Re: BFS Survey Update

PostPosted: June 18th, 2011, 4:27 pm
by pbohan
We now have 52 participants and counting. I will keep the survey open as long as we continue to get new inputs.

Re: BFS Survey Update

PostPosted: June 26th, 2011, 9:17 am
by pbohan
We are up to 55 participants. Keep the responses comming, we are moving towards a significant sample.

Re: BFS Survey Update

PostPosted: July 3rd, 2011, 9:17 am
by pbohan
We are up to 57 participants in the survey. Thanks for participating and hopefully we can continue to grow the sample size even further.

Re: BFS Survey Update

PostPosted: July 10th, 2011, 4:42 pm
by pbohan
We are up to 58 participants. Please respond to the survey if you have not already done so.

Re: BFS Survey update

PostPosted: July 17th, 2011, 3:09 pm
by pbohan
We now have 60 participants. Keep the responses coming, we certainly have nothing to lose. Thanks for participating.

Re: BFS Survey Update

PostPosted: July 24th, 2011, 8:18 am
by pbohan
We now have 62 participants. As long as people continue to respond, I will keep the survey open. The better the sample the better the results.