Testing and Statistics

[TheTartanPimpernel]

This thread is a split from ,' Please Explain something for me ' in 'Ask the Experts'.



I only ever tested twice a day; before breakfast and before my evening meal.

I managed my HBa1cs to between 5 and 6 by removing all biscuits and sweets/puddings and by adopting portion control which, by its nature, reduced the volume of carbohydrate I consume.

My view is that you do not have to eat to the meter. However, it is also my view that you have to record all of your test results and do some sort of analysis on the accumulating data. Its no use whatsoever simply testing and noting the results - unless the data are recorded its pretty meaningless. I used a simple spreadsheet and graphed actual readings for the two data streams, the daily average, a couple of moving average (to provide a 'smoothed' view of what was being recorded) and linear trend. My target was to get between the tramlines I set at 4.5 and 5.5.

Having made the range 5-6 I am reasonably happy and do not feel that my food intake is much restricted - its now probably where it should have been years ago. My GP thinks I have room for relaxation but having acquired better habits I prefer to stick with what I am doing.

 

[RichardNY]

Re: Please explain something for me !!

My view is that you do not have to eat to the meter. However, it is also my view that you have to record all of your test results and do some sort of analysis on the accumulating data.

Surley you need to use your meter to get those good results ? Maybe I wasn't clear enough "eating to your meter" in my view is getting good results building up that good list which means testing before you eat, 1hr after and 2hr after not just a before breakfast and before an evening meal (How do you know the effects of what you are eating if you never test after ?) Surley just testing before breakfast and before an evening meal never lets your meter identify the bad foods ? and therefor you cannot eat to your meter or build up a good food list that your meter tells you is good to eat.

I am glad your method works for you but am confused as to why when you never identify the foods that spike or increase your blood glucose.

Is your HBa1c the one tested by your Dr or is that just an average of your spreadsheet as they both use differnent forms of measurement and averageing.

I am however going to make a slight observation if you construct a test to measure an average using minimal readings (2 per day) then average an already average reading on a linear test with result that every morning with roughly be averagely the same or linear in nature ? (you will get no deviation or very very little) The variable is the food that we eat you are not recording or measuring that variable you are however measuring values which will be roughly the same and obtain a linear consistant average.

In a nutshell the method of testing is flawed your setting yourself up to measure the same thing everyday an average with no variable of food that alters the blood sugar ... remember this is in a type 2 context. The emphasis is on finding the highs and spikes.

"However, it is also my view that you have to record all of your test results and do some sort of analysis on the accumulating data. Its no use whatsoever simply testing and noting the results - unless the data are recorded its pretty meaningless."

Your testing has to include the variable that makes our blood sugar rise and has an impact on us that means testing after a meal. Your testing method did not include this only as you state before you eat in the morning and before you eat in the evening.

I'm sorry but I disagree with your method of testing and not using the meter to build up a good list. I took it for granted that a "meter eater" or someone that "ate to the meter" was collecting data and establishing an average via the use of that meter in particular the nano meter as mentioned by Rick that works out your average for you 7/14/30 and 90 days. The option to record on a spreadsheet is always there something which I do but that spreadsheet also includes the lists of good/medium and bad foods.

I apologise for assuming that people knew how and when to test.

Test a few minutes before you eat.
Test 1hr after
Test 2hr after

at a bare minimum

Test before you eat
Test 2hr after

Use the readings to build up your good and bad food lists. I also find its useful to repeat test for good and offending foods (3 strikes and there out as it were)


All the best Richard.

 

[TheTartanPimpernel]

Re: Please explain something for me !!

My first action after being diagnosed was to set about establishing what 'normal, blood glucose readings might be and how various foodstuffs might affect a diabetics blood glucose. The next step was to eliminate from my diet anything I considered extraneous, i.e. no sweets, no chocolate, no jams/marmalade, no honey (hard for a man who keeps bees) no ice cream, no biscuits, no sweetened soft drinks (I have never added sugar to tea or coffee), no puddings etc., etc. Most people, including my GP and the consultant, at that point said I was over-reacting. I prefer to say focussed.

That left the hidden (but fairly obvious) main sources of glucose in my diet. I added pasta to the no list; it was something that I was particularly fond of and ate in large quantities - having had an Italian Godmother. Sadly, I also added porage oats - something I ate most mornings with wheatgerm. I then set about to portion control 'staples' which had a high carb content or that I had a particular liking for. This led me to serious reductions in my intake of bread in its many forms, potatoes, rice, couscous etc and to similarly limit what I ate by way of root vegetables. Unfortunately, it also led me to reduce my intake of some things I ate simply because I liked eating them, for example cheese and lots of it in its many forms, grapes and many other fruits.

I have never tested, ate, then tested to see the outcome - and I think I have I have a good outcome. So, arguably, my methodology was/is not flawed. I simply eliminated what I considered were the readily identifiable 'baddies' and plotted the results of my two daily tests. Looking at averages and moving averages simply helps smooth out some of the lines. Looking at a linear trend (there are other trends you can examine for the same data set) simply enables you to extrapolate and this allows you to perhaps consider the extrapolated value as a mini-target on the journey towards near normality. What a boost when you just miss a target and what a better boost when you come in under the wire.

If nothing else I am not stupid. I am very aware of the differences in BG and HBa1c testing. My HBa1c is now done twice per annum - I attend the surgery, the leech removes the blood samples, the lab does the business and provides the results and within a few days I phone the surgery and get the full results list along with my GPs comments. I assumed that all diabetics did something similar

My testing had nothing to do with establishing an average value for the day, the week, the month or for that matter any other time period. Having established what a normal blood glucose level might be I set out to collect, record and track the data from my samples relative to my chosen 'normal' bandwith. On the journey it was useful to convert and compare values for the dates that, my initially 3 monthly, HBA1c results arrived. I simply set a target, a goal and observed the movement towards that goal. Simple, with few variables to consider, I was testing the blood glucose outcome of my chosen dietary regime - overall I was eating less and I was eating less carbs (by eliminating the real baddies) and by reducing those that remained in my diet through controlling portion size.

No need to apologise for assuming that most people knew how to test. I would argue that the eat by the meter regime you offer tests too often and produces too much data and further that you make assumptions about the outcomes that may or may not be valid. I would not be surprised that if you ate A+B today and tested X and went on to eat A+B tomorrow and test X+n (or indeed tested X-n). If you eat A + B and test X then eat A + B + C and test X+n then you are assuming that C is the cause of the increase, it might well be - but then again it might not.

However, as I obviously don't know how to test - silly me. Nevertheless, I might reasonably argue that the outcomes of my chosen regime are not due to chance and that my testing regime gathered sufficient information to direct me to my chosen goal. I have no diabetic complications. I am probably a healthier person since diabetes was diagnosed and in many ways I am grateful that it was.

I obviously don't believe in using sledgehammers to crack walnuts. No need to make life more complicated than it already is. But then again there is nothing like amassing a vast amount of detailed and for a large part arguably spurious information to keep oneself occupied.

Softly, softly catchee monkey.

 

[RichardNY]

Re: Please explain something for me !!

I'm sorry but I still disagree with your method of analysis its an area I know something about I have in the past been employed to provide Quantative analysis in the finance sector through employment in other sectors dealing with complex numbers (Isolated singularity and meromorphic functions) at the the opposite end of the spectrum. I say this only so that you know that I construct and test data collection and analysis methods and also have to submit them to peer review.

I think what you have done is set yourself up first with a method of exclusion that has by chance luck or extremely good guess work eliminated the things most likely to cause blood sugar highs for you. But your method of analysis cannot support this from the way you construct it. In other words it's a coincidence. Why? because you measure at a time that most diabetics would have their lowest readings anyway. Remember again this is in a T2 context.

You then take small and in this context of testing meaningless readings you then also include another moving average.

You do not test after food when the value of the variable is available. The most important factor.

Looking at averages and moving averages simply helps smooth out some of the lines.

- On an incomplete data set with a small sample size and one which totally ignores the variables your line will be smoother than smooth in fact extremely straight!

These are not methods of using a sledgehammer to crack a walnut because once you know what foods do to you, you can relax on the testing because you will know your safe foods. There are many other useful outcomes of regular testing too but in essence and in a nutshell it gives you a complete picture of your condition and how and what you react too.

There are other variables which you cannot control but to diabetics food is the one variable they can. Your meter and the readings it provides are the best tools on a daily basis to provide this.

I think we are moving away from the original question of the poster here and if you like we can start another thread and not hijack someones thread (as the original question was about the reasons for low carbing and not methods of testing and analysis)

I have to say that a testing method and indeed an analysis method as you are suggesting is much like riding a bicycle up a busy one way street, you'll only get away with it for so long ...

All the best Richard.

 

[hanadr]

Re: Please explain something for me !!

Some of You guys seem to want to do a Ph D in statistics. This may be the obsessive behaviour that the "Establishment" are worried about.
I find it sufficient to test twice a day. Not at the same times and to keep the results below 6 at all times. I do extra tests if something shows up that seems out of kilter.
For example I've just had a course of antibiotics to clear a UTI. I found keeping on target difficult.
I finished the course and am back on track.
Since metabolism is a complex set of processes, There's not a lot of point in collecting endless data and processing it. All it needs is for a colder day tomorrow, for everything to be different.
You need to know if you are onto your personal targets and which foods do what. Any more isn't going to help anything.
Hana

 

[Rob49]

How Often to Check BS

Firstly I am one of those lucky people who gets my strips on repeat prescription. I attended a recent 6 monthly check at my local surgery and during this showed the Diabetic Nurse the results of my daily testing of BS, including a 7-day rolling average; something I do each morning (fasting) before breakfast. I have been doing this for the last 7 years with no critique from any of the health care people, including Consultants, that I have come across. Well the DN told me I had got it all wrong and that I should measure my BS 2 hours after each meal and that the BS recovery (from high back to normal) was much more important than the fasting level. Well I am ready to consider this, but before my fingers become pin cushions I thought I would consult the Oracle - sorry I mean the forum

Rob49

 

[ShyGirl]

I'm not sure aboout the best time to test as some say an hour after eating and others claim 2 2hours. My consultant was surprised when I said I wasn't testing much at the moment and I forgot to tell her what was said to me at my clinic two years ago when I asked for more strips "The consultants at the (my hospital) say T2's don't have to test".
I have often wondered if Habc1's show an accurate picture of what is happening in your body and what spikes do in the long run as you can't catch EVERY high reading.

 

[sugarless sue]

Testing just before a meal then two hours after is the norm. The reason, however, to test one hour after is to look for 'spikes' if you suspect something is sending your blood sugars up. I did this with oat based products as I did not understand some highs I was getting.
Sometimes, if you eat a very fat based meal a three hour test can be done as the fat slows down absorption.

 

[ShyGirl]

Is it possible for a Diabetic to be a 4% though? I wonder what the lowest is for a diabetic
I

 

[hanadr]

Yes Shygirl
Luck and genetics
but there's no reason why we sshouldn't all help our luck a little with the best control we can manage.
Hana

 

[TheTartanPimpernel]

Perhaps I should end my comments on this thread by repeating that the use of the two daily test results was to show that my diet regime was having a positive effect and reducing my blood glucose levels towards the target hat I set. It sees to me that the simple methodology did exactly what I set out to do, nothing more, nothing less, with minimum effort.

Having spent 10 years of my life within the government statistical service dealing with the analysis of morbidity and mortality data, occupational mortality etc., I think I know what level of testing was fit for purpose. If I had wanted to test for the impact of specific foods I would have done so - and that analysis would not have been based around mealtimes.

 

[cugila]

Having spent 10 years of my life within the government statistical service dealing with the analysis of morbidity and mortality data, occupational mortality etc.,

TP.

So, you might be one of the ones who made me fill in reams of statistical forms at every RTA I ever dealt with........ :wink: Everybody knows government statistics prove what they want you to hear, not what actually happens. I think I'm with Richard on this one - your methodology is definitely flawed. It only proves what you want to see.

How on earth can you say that testing twice a day proves everything is 'hunky dory ?' OK, so your HbA1c is great, no getting away from that. I just hope you aren't missing the spikes and troughs ?Remember though it is only an average, not definitive. As a Cop we used to use VASCAR (Visual average speed and recording) devices. Quite often a motorist would be stopped and asked what his speed was, he usually answered, "30 guv"....when shown that his average speed was nearer 45 they would usually admit to doing around 60 at one point, so in effect they got away with an awful lot, because averages are rubbish. Cover's a multitude of sins.

Here is an example for you from my Bg levels recently.
Fasting (waking)....................4.2 mmol/l.
1 hr after Breakfast................13.4
Before Lunch........................10.3
2 hrs after Lunch....................6.0
Before Dinner.......................3.6
2 hrs after Dinner...................7.9
Before bedtime.....................10.2

Total of 55.6 divided by 7 = average of 7.9 mmol/l. Now this figure is within the 'infamous' NICE guidelines so would seem to be OK ? Not the case. As you can see my blood sugars have been all over the place, hypoglycaemic, hyperglycaemic. I am only aware of them because I test frequently.

That was the whole point of the original thread which this was split from, to give a new poster advice on frequency of testing. A related subject. A very important subject too in my opinion

Using your methodology I would be oblivious to all of this and my average would be around 3.9 which would seem miraculous, great for some, bad for others. I really do wonder just what your method is missing TP. I have a friend who used your method as advised by the GP. He thought because all his numbers were in the 5's he was doing great. HbA1c was good as well. He is now seeing after taking some advice to test more frequently that his numbers are far from great, they are at times appalling !


BTW folks.....I don't need advice on my Bg control, I know exactly what is affecting it at the moment and I can do nothing about it other than try to cope by adjusting carb intake as and when. Thanks.

 

[cugila]

BTW folks.....I don't need advice on my Bg control, I know exactly what is affecting it at the moment and I can do nothing about it other than try to cope by adjusting carb intake as and when. Thanks.

This is where you have to ask the questions and not just take things at 'face value.'

Let's just say, it is an extremely powerful non diabetic drug I am having to take 3 times a day which is affecting my Bg levels in all sorts of ways. I could give you even worse days !! For somebody who is used to a 98% target figure being achieved throughout a month to suddenly go to about 30% in a couple of weeks is pretty disheartening in itself. Which is why I said I know what is causing it, not MY loss of control, but circumstances BEYOND my control I'm afraid.

 

[cugila]

Normal BG'.....has to be individualised as well. Some cannot hope to achieve some of the lower numbers posted by others. We all strive to do our best, that's all we can do. Sometimes we fail, that's life.

NONE of my readings prior to this were any more than around 6 - 7 including 'spikes' which I actually didn't get before all this started. Down to a much reduced carb and low GI/GL diet. That virtually eliminated any spikes. In my opinion I don't want any spikes, if there are any they remain within my target range, or for now at least the nice guidelines (less than 8.5 mmol/l. Anything outside of that and you are asking for trouble in my view. That's why my present predicament is so frustrating. :roll:

 

[sugarless sue]

When I had a plentiful supply of test strips (we won't reopen that discussion here) I used to test the blood of many people just so that I could get a comparison with mine. Frequently, I recorded fasting and 2-hour levels, which confirmed non-diabetic status, and then 1-hr levels that were 13, 14, 15mmol/L (and much higher than mine!). I would not begin to suppose that my small sample could be used to infer anything other than a view that 'spikes' happen - and apparently happen for non-diabetics just as one would expect them to happen for diabetics. If I were to draw a conclusion I would have to say that those tests indicate that not everyone has a daily BG profile which conforms to the view of non-diabetics always having BG levels below 10. In my limited experience that is simply not true (but, of course, that is my limited experience). But if you feel inclined take another look at the WHO paper and see what it says on the subject of 'normal' BG levels - it's quite an interesting view.

Yes non diabetics get spikes in their blood sugars as well, the difference is in how well their insulin production deals with it to bring it back to normal. That is the distinction between non diabetics and diabetics and what the GTT test picks up when it is carried out.

 

[graham64]

Is it possible for a Diabetic to be a 4% though? I wonder what the lowest is for a diabetic?
I just wish there was a cure as some people abuse themselves , eat what they want and there Diabetes is ok. Others have ridiculous complications . I guess it's down to luck as to why some people can handle porridge or cake.

Hi ShyGirl,

Yes it is possible to have a HbA1c in the 4s Fergus a T1 consistently achieves sub 5s, and on another forum we have a T2 with a HbA1c in the 4s :mrgreen:

Regards
Graham