Why one result is not enough
A result can be a little higher or lower on any day because of the time of the sample, what you ate, how well you slept and the natural variation of the test itself. A pattern across several reports tells you far more than a single value. That is why doctors ask for your earlier reports.
Keep every report, with its date
The first rule is to keep every report, including the ones that looked fine. The date on each report matters: results are only useful if you know when they were taken. If you only keep the abnormal ones, your history will tell a lopsided story.
Compare like with like
A fair comparison needs the conditions to match as closely as possible. Note these for every report:
- the lab, because methods and ranges differ between labs
- the unit, because a change of unit changes the number
- whether the sample was taken fasting
- any medicine you had started or stopped since the last test
Which tests people follow
People most often follow tests that their doctor repeats on a schedule. Examples are cholesterol (total, LDL, HDL and triglycerides), HbA1c, hemoglobin, vitamin D, vitamin B12, thyroid tests such as TSH, creatinine and ferritin. Your doctor decides which ones matter for you and how often to repeat them.
Do not over-read small changes
A small change between two reports is often within the normal variation of the test, or the effect of a different lab or method. A change in a result is a reason to ask your doctor, not a reason to change your medicines or your diet on your own.
A simple way to keep the record
A table with one row for each report works: the date, the lab, the test, the value, the unit and the reference range printed on that report. Add a column for notes, such as fasting or a new medicine. A chart of one test across the rows shows the direction at a glance.
MyCareTrack does this for you. Scan each lab report and its results join a chart for that test, drawn against the range printed on your reports. Open Records, then Test trends, to see every test, and compare two reports side by side to see the change in each one.