Layout
The HbA1c Tracker has eleven parts:
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• Info box |
| • Body |
| • 3 drag and drop HbA1c (%) headings (tight, medium, loose) |
| • 3 drag and drop Glucose (mg/dl) headings (tight, medium, loose) for plasma blood glucose readings |
| • 3 drag and drop Glucose (mg/dl) headings (tight, medium, loose) for whole blood glucose readings |
Capacity
The body of the HbA1c Tracker is divided into 120 rows, one row per glucose reading. At an average of 4 readings per day, one printout covers one month. At 8 per day, two printouts cover one month.
The headings and body are divided into 12 columns. The 10 center columns (marked by a yellow band on the headings) define the range of readings covered for tight, medium and loose control. Each of the 10 center columns covers an equal range of readings.
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Plasma Blood Glucose (Newer Home Glucose Meters) | |
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Color code |
Glucose control level | Interval and maximum predictive accuracy | Covered range |
| Blue | Tight | 7 mg/dl, 0.2% HbA1c | 97-167 mg/dl, 4.9-6.87% HbA1c |
| Green | Medium | 18 mg/dl, 0.5% HbA1c | 83-260 mg/dl, 4.5-9.47% HbA1c |
| Red | Loose | 36 mg/dl, 1.0% HbA1c | 65-420 mg/dl, 4.0-13.97% HbA1c |
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Whole Blood Glucose (Older Home Glucose Meters) | |
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Color code |
Glucose control level | Interval and maximum predictive accuracy | Covered range |
| Blue | Tight | 6 mg/dl, 0.2% HbA1c | 87-146 mg/dl, 4.9-6.87% HbA1c |
| Green | Medium | 15 mg/dl, 0.5% HbA1c | 75-224 mg/dl, 4.5-9.47% HbA1c |
| Red | Loose | 30 mg/dl, 1.0% HbA1c | 60-359 mg/dl, 4.0-13.97% HbA1c |
The first and twelfth columns collect "overflow" readings not covered in the ten center columns.
First time setup
Open in Microsoft Word. Type name and start date in info box. The HbA1c Tracker is set to open the first time with the medium control headings for HbA1c and plasma blood glucose in place. If your meter tests whole blood glucose, replace the glucose heading with the medium whole blood glucose heading. If you are unsure which type of readings your meter gives, check your instruction book or contact the manufacturer.
Drag all unconnected HbA1c and glucose headings to second page. Print page 1.
Record readings from glucose monitor as dots
Keep your Tracker sheet with you. Whenever you test your blood record the reading as dot on the chart.
To record a reading simply find the column where the reading falls and use a pencil or pen to make a dot on a red cross in that column.
Each row should contain only one glucose reading. Always start a new printout with the row closest to the glucose heading.
Stack readings to form histogram (for more on histograms see HbA1c Tracker overview)
Shade the cells within columns to construct histogram. For every dot in a column one cell should be shaded. However, not every cell with a dot will be shaded. This is because dots are spread out in the tracker, but shaded cells are stacked. For example, the column in the diagram (which is turned sideways) has dots in rows 1, 14, 32, 53 and 74. To form this column's portion of the histogram, collapse readings to the first five cells (starting with the cell closest to the glucose scale).
Readings can be stacked as dots are entered, stacked when all rows are filled, or stacked in batches at anytime in-between.
Interpreting first histogram
At the end of the month, analyze completed histogram.
Size up the shape and tightness- Does histogram have an identifiable "shape"? Is it symmetrical (like a bell curve)? Do most readings cluster in just one of the ten center columns? Do they pile up in one or both "overflow" columns? Compare to model shapes and troubleshoot as indicated.
Estimate the first month's HbA1c range- In a symmetrical histogram with a pronounced central bar, the range of the central bar corresponds to the most likely HbA1c range over the previous month. Of course, this assumes the histogram is made up of glucose tests that are both accurate and representative, and that a large enough readings sample has been included.
If a user's first month histogram prediction is materially different from her most recent lab result, she should review the histogram with her healthcare professional before starting a new one or adjusting goals.
Setting goals and improving control
When it comes to goals, generally diabetics should strive to achieve before meal readings within the range of 90 to 130 mg/dl (whole blood glucose)* or 100 to 150 mg/dl (plasma blood glucose). Unfortunately, the readings many diabetics encounter are far from this, and sometimes their readings plateau in an unacceptable range. One approach to tighter control is "continuous improvement".
The layout of the HbA1c Tracker and the tool's monthly frequency lend themselves to incremental goal setting and the notion of continuous improvement. For some users it may be beneficial at the start of a new sheet to draw in lines representing "must hit" goals:
- Line(s) representing upper (and/or lower) glucose limits
- HbA1c range
In the case of glucose limits, the cause of each reading outside the goal should be explained and noted by hand on the tracker.
In order to get the most from setting goals for continually improving, users should:
- Set realistic goals-- goals that can be reached, but require increased effort
- Tighten goals each month
- Always involve their healthcare provider
- Never set goals that jeopardize other aspects of their diabetic therapy or endanger their health
Predicting HbA1c
Prior to a lab test average the estimated HbA1c for the preceding three months to determine your overall estimate. For example, suppose there are these estimates: Month One 6.7 to 6.87 HbA1c, Month Two 6.5 to 6.67, and Month Three 6.3 to 6.47. Add the lower members and divide by 3. Then add the higher members and divide by 3. This gives the 3 month estimate. So, (6.7 + 6.5 + 6.3) / 3 = 6.5 and (6.87 + 6.67 + 6.47) / 3 = 6.67. The three month HbA1c estimate is 6.5 to 6.67.
A number of factors can cause actual HbA1c to differ from the estimate. Users should always review with their healthcare professional any disparity between an HbA1c result and the estimate obtained from the Readings Tracker. When analyzing results with their caregiver, users should also provide their completed Tracker sheets. This documentation will assist the caregiver in spotting underlying problems.
Day to day tracking
The HbA1c Tracker may be used to follow movement in day to day glucose readings. Dots may be connected to form a time series, color coded to compare readings from different times of day, or easily partitioned to show changes from day to day or week to week.
How the HbA1c Tracker is used in this regard depends on the nature of the logs and charts are already kept by users. The Tracker visually demonstrates changes from range to range (column to column), but does not capture individual readings. It is not meant to replace logging and tracking individual glucose reading numbers.
