Reading Lab Test Results

a lab report showing the conclusion of results "satisfactory".

Q: What Does word “Satisfactory” results mean?

Hi what does mean that’s

a lab report showing the conclusion of results "satisfactory".

When your results screen type “satisfactory”, then it’s simply means you have no bad findings and your results is just fine and you should not worry about harm or bad issues in your lab test results.
But, this is for the already done tests, while other tests you don’t take we still don’t know what they are yet.
Also, this doesn’t mean that your health is perfect as this flag is for the current test result.

It’s one of the terms used in the lab reports to help people simply know what the conclusio of there results, similar like using “A” letter before or after the final result values, read more about flags and alarms on test results.

logo all flags on results

Red Flags H, L, A, C, Astric, Stars, Arrows on results, what is meaning, does that bad? should I worry?

Decoding all flags, signs and symbols that appear on the lab test reports, if you were looking for a test code used in the lab as abbreviation to the test itself please visit lab test codes


  • Meaning of arrows near of results
  • Symbols “Astrik” and stars (* and #), what does they indicate?
  • Red color
  • Orange color
  • Green color and the letter “N”
  • Grey/Gray shadow
  • Flag H, Flag L, Flag A and Flag C
  • Warning exclamation triangle
  • Signs minus(-) and plus(+)
  • What does “+1, +2, +3” mean on test results?
  • Technical Flags
  • AG* on platelet count

Basically, marking or highlighting a word or phrase in a book page is believed to grab the reader’s attention to that word or phrase that there additional information to know about that point, the same thing with the lab test results the laboratory usually highlight the unexpected results to ensure the reader don’t miss them, below you can find most used marks, signs, notations and flags with the appropriate interpretation.

Are you looking for explanation of what is the meaning of a lab result in red or green or the result has placed near down arrow or above arrow?

Generally, if your lab results followed by signs, flags, marks, symbols, or printed in different color than other results, surely these findings are abnormal results of a certain degree, however, abnormality doesn’t necessary mean harmful condition, please read the details carefully to decoding your labs and understand well…

The report shows most of abnormal flags, H L, A, C, red, green, orange, gray, warning triangle
A report shows most of abnormal flags

What does the result in red color mean?

Always, the red color means “risk”, when the patient’s result exceeds the normal nominated limits for a test (either above the high limit or below the low limit), the lab print the result is different color than the rest of the words in the document, usually the red color means abnormal finding that is require attention and treatment.

Some labs print the patient’s result on a red bar, also, it means the results is outside the reference range and it’s important to understand that well.

I got my lab result shown printed on an orange color bar?

The orange color means that the test result is inside the grey zone or on the borderline levels, that does mean your numbers neither high, nor low, nor normal. Such lab final results need more confirmatory tests, more sensitive, more specific tests or repeating the test again after few days which let the values adjusted and be clearer.

What is meant by the results when written in green color?

Usually the green color means safe, based on that the medical labs use the green color to distinguish the normal findings from other abnormal results, the same as the letter “N”, and greenish line, all share the same indication, the normal safe result.

The normal result is a lab finding that is inside the reference range and considered a healthy non-risky level and doesn’t require a treatment itself,

however you may have a normal finding in some test and abnormal finding in other tests, therefore the treatment plan or the final diagnosis is based on the whole information gathered from lab findings along with clinical examination and imaging results not based on a single result, so take care of the final interpretation of your lab test results.

For example: having normal random blood glucose value doesn’t mean you don’t have diabetes, because there’re blood test A1C to detect the history of accumulated glucose in the blood and diagnose the diabetes effectively than the RBG test.

Alt test and the result is normal and on the green area
Creatinine test and the result is normal and on the green area

What is meaning of test results that on gray shadow?

One of the simplest methods to differentiate the results that exceed the normal range is to print it on gray color highlight or grey shading the abnormal findings.

What do the letters “A”, “H” and “L” on a blood test result stand for?

The Letter “A” stands for the word “abnormal” which means a lab result that is outside the reference ranges either above or below limits. The “H” letter stands for the word “high” which indicate an abnormally elevated lab test result. The “L” letter stands for the word “low” which indicate an abnormally decreased lab result.

Also, the letters may be in the color red or without special color. sometimes arrows or stars and letters added together to emphasize how risky the results are.

Examples: visit, meaning of flag “A”, Flag “H” on PLT, Flag “L” on PLT, Flag “C” on results

What do the single arrow and double arrows near the lab results mean?

Promptly, the result with the arrows nearby is generally abnormal or out the common familiar norms, thus the laboratory prints the abnormal sign “arrow” beside the written value in the final result.

However, the single arrow marks the abnormal finding but doesn’t tell if it was mild or severe. On the other hand, the double arrows mark a sever abnormal result which requires urgent medical decision.

Double arrows to the downside is similar to the abbreviation “C” which means “very low” but not critical yet, likewise, if the result is printed with double arrow to the above it means that the result is “very high” but not reaches the critical level yet

lab report show abnormal results highlighted in red and arrows
lab report show abnormal results highlighted in red and arrows

My lab results got a flag ‘Astric’ right to the number, is that mean an issue?

A frequent question sent nearly every day to the website and the FB group, simply, the lab prints the sign looks like the star “*” or “#” on your numbers that are not inside the normal reference range, the reason is to highlight the untypical or unexpected findings in the printed lab report. Some labs add two red stars near the abnormal results to indicate it’s exceeded the normal range too much.

Therefore, Astric or stars flags mean “an odd results” that come beyond the expected values of the same age and gender, although flags don’t always mean a bad situation.

How to distinguish the Abnormal Results from Normal Results on the lab Report?

Normal results written in black color or greenish color, green bar with the value above it or below it, the letter “N”, or without any marks or flags. On the other hand, the abnormal results got a flag of many types such as (writing the result in red color with or without stars, arrows, double arrows, or writing results accompanied by one of the letters “H”, “L”, “A”, “C”), shading the abnormal result with a grey color is another way to represent that it’s a different than other normal results.

What is meant by “out of range” with exclamation and danger triangle?

The range, means the reference range or the normal nominated range for the same age and gender of you. being out of range or outside the range is referring to abnormal results. Yellowish or reddish exclamation triangle means “warning”.

The meaning of flags like “Plus sign and a number”

Flags consists of “number and the sign plus+” means “how much is a quantity while testing for something?”

The Flag “+1” means “Mild or simple amount” or “positive one level or at the first degree”, likewise, the “+2” stands for “moderate amount”; “high to the second level”; or “elevated to the second degree”, “3+” means “large amount, big amount, a lot of, to the third order, at the third levels, elevated to the third degree, etc”

A urine analysis report show the flags “H”, “+3”, “+1”

Examples: on the image you may see “+3” on a result of the quantity of blood in urine which typically means the urine analysis revealed that there’s a lot of blood in urine which is abnormal that’s why it’s flagged. Other labs may write it as “Hematuria 3+

The same example report shows: the result “protein 1+” which means simple amount or little amount of protein (has the medical term, proteinuria 1+) which is abnormal but mild condition.

The meaning of the signs minus(-) and plus(+)

Minus sign”-” before or after a test result means “Low”, while plus sign “+” before or after the results means “High”, the same as “H” and “L” abbreviations, the example shown on the image below (the red arrow refer to the minus sign).

Technical Flags: Astrik, Window sign, WL, MP

If you received a copy of your results printed on the instrument’s paper like this,

A CBC report show many technical flags and medical flags
A CBC report show many technical and medical flags

The image show flags on red circles that alert the lab technician that there’re something not complete or the procedure background has got some technical errors and he/she must repeat the test or do other maintenance to let the instrument adjusts and fixes the final results next time.

The technical flags such as “WL, MP or *#” appear on the instrument’s printout only which must not gave to the patient because it still not final yet. the example above shows a report of the full blood count test from the instrument screen which has many technical flags for the lab technician to deal with such as:

“AG*” flag, abbreviation to the word “Aggregations” which alert the lab technician to do another examination of blood film to confirm either natural decrease of platelets count or the decrease is due to aggregations of platelets which may be due to error in the blood sample itself or due to malfunction in the instrument and needs troubleshooting.

My labs got red symbols, is the flag near the result a bad thing or of good things?

Results that printed in a flagged manner is surely non-typical or outside the reference ranges but it’s not always a bad result because the annotation is used for just paying your attention to this different finding. For instance, the annotation on the positive pregnancy test result is to grab your eyes towards the unusual finding but it’s a good finding for a female to be pregnant.

When should I worry about Red Flags on my lab results?

All flags are designed to alert that your results are abnormal but only the flag “C” or “double arrows” that mean “extreme abnormal” to a degree of panic, undesirable, worrying or uncommon and must get prompt medical care.

If the result is not highlighted or flagged, it does mean a normal finding, and doesn’t mean less important or has no importance, for sure it is important for overall diagnosis but the flags is for just alerting the reader for abnormal results only.

Examples 1:

HbA1c (NGSP) 8.1 H at first, 7.3 H after treatment 6.0 N,(the reference ranges 4.0-6.0 %)
HbA1c (IFCC) 65 H at first, after follow-up and took treatment become 42 N (reference range 20-42 mmol/mol)

Explanation: The patient number is printed in red and followed by the letter “H” to indicate it’s outside the expected range and therefore diabetes, while after treatment the result is followed by “N” and printed in ordinary color which means it reaches the target range for the diabetes person.

Example 2:

Haemoglobin test: first visit was 118L, second visit was 132 L, third visit was 146 (normal ranges 135-175 g/L).

Explanation: The final lab report show the hemoglobin result two times elevated so that the numbers is highlighted in reddish color and followed by “L” flag to be understood that it is anemic, but finally the hemoglobin level returns inside the normal levels and the lab printed the result in the ordinary color without flags, signs, or letters to indicate “it’s safe level, no medical issue”.

Note that in both examples 1,2 the high and low results are highlighted in red color because they both outside the normal levels.

Example 3:

Qualitative pregnancy test (hCG): Positive*
Quantitative BhCG test: H 550 mIU/mL

Explanation: the pregnancy test shows the word Positive which means there’re pregnancy, but the quantitative test of the pregnancy hormone revealed that it was 550 followed by “H” which means high quantity of the pregnancy hormone, therefore the flags printed here “H” and “*” pointing to an elevated level in despite of bad or good outcome.

Example 4: Flag H before plt and wbc

Who writing my test results report? Who made the highlighting marks on my labs?

The lab pathologist or specialist is the responsible for writing the final lab document that assess your doctor to indicate the appropriate diagnosis. Interestingly, modern laboratories don’t still write on papers, instead they use programmed platforms or medical electronic devices to write the final reports, and those platforms programmed to highlight the abnormal findings according to the recorded reference ranges inside.

Why print results with flags and highlighted marks?

Eliminating the confusion when reading lab results and confirm the abnormal results.

When you open a lab form it may show many numbers, codes, uncommon words or symbols which make you brain stopped and become confused, therefore the colored marks and flags act as pointers on the abnormal findings to erase such confusion and facilitate the reading of the whole report.

Can I ask my doctor for a copy of my blood test results?

It’s from your legal rights that allowed by most healthcare providers and medical laboratories to receive a copy of your medical reports and lab results, therefore if you didn’t take the by default just ask you healthcare provider who ordered the lab tests for the copies.


Concluding the meaning for the lab codes of abnormal results
Concluding the meaning for the lab codes of abnormal results

If your blood result has a grey shadow or is surrounded by a mark or a flag (i.e. star, L, H, A, C, arrow) or written in red color, it means that your result exceeded the normal reference range and the lab highlight it because it’s “abnormally important”, but, if the result is written in the usual color or highlighted by the green color or the results followed by “N” sign, it means normal healthy finding and has no medical issue.

If you still can’t decipher your lab results you can post, messaging, or Facebooking with us anytime.

red flag C critical on a lab result

What is the Meaning of Red Flag C Near My Lab Results?


  • Meaning of the letter C beside labs & blood test results
  • When results are flagged with the “C” notation?
  • Why the label “C” printed in the lab test reports?
  • What is the meaning of a Critical Level?
  • Which test results don’t flag with the critical mark “C”?
  • Examples
  • Meaning of reddish double arrows and star

The Abbreviation “C” stands for the word “Critical” which may appear near a lab test result and means that the result is extremely abnormal either high or low. Some labs print that reddish letter “C” beside some of patient’s results to highlight the very risky and urgent lab result, and here some details to read and understand your lab test report easily and effectively.

Also, Critical or Panic values in the laboratory terms mean sudden or prolonged uncontrollable lab test results, often causing another severe complications.

The critical test result is the lab finding that experimented to hold greater health danger or extreme risk by exhibiting mad multiplication of the normal limits.

Generally, the lab finding must be compared to a reference range, a range of two normal limits at least that tell us what’s the normal or abnormal, but sometimes the abnormal values of a lab test exceed the normal limit many times,

for instance, the uric acid test has the normal limits 3 and 6 when the patient’s results found in between these limits it written normal and the patient doesn’t have to receive treatment, if the uric acid result is 6.1 or any value below 11.0 the lab describe it as “high” and have the flag “H” and the patient should receive treatment anytime later to lower uric acid levels but it’s not urgent,

but when the uric acid value jump over the limit 12.0 the lab flag it as “C” which means the uric level is at the critical or panic level because it is double the normal limit and this that must take appropriate treatment promptly without delay.

The reasons of Flag “C” beside the lab test result

The typical reason is that the lab finding is too much high or too much low to the emergency degree that must immediately meet the doctor and take immediate treatment to adjust the blood test to its normal healthy levels, and any delay can prone the patient to great health issues to a very big degree “in ordinary-people words”.

The lab report designated to show the codes like “C” to ensure that the emergency indicators in your results will not miss during exploration of the whole results

Examples of lab tests that may show with “C” mark:

Lab test results that reported in numbers may have critical levels, for instance, the Glucose test, Creatinine test, urea test, Hemoglobin test, HbA1C , Liver enzymes, Testosterone test, COVID-19 antigen and PCR tests, etc.

example show different flags "A""C"
Real-case example of flag “C” on the platelet value

Tests that don’t require the critical mark:

All test that reported in “negative” and “positive” system don’t necessitate to have critical levels, for instance the pregnancy test and qualitative virus B test.

Difference between flag “C” and other flags in the lab report:

Flag “A” means abnormal result but doesn’t distinguish the abnormality if it was low, mild, moderate, or very severe, just mark the result to pay attention to.

Flag “H” means a “High” result obviously but doesn’t distinguish mild elevated from severe elevations, just say the level is outside the higher normal limit.

Flag “C” means not just a high result or just a low result but annotate “extreme elevation or decreasing” in other words the results is “abnormally elevated or decreased many-times over the greater limit of the normal range”

Flag “L” means that the result is “Low” Exclusively but doesn’t provide how low is it.

What to do if your lab results are highlighted with “C” Flag?

Without delay, you must go to the nearest doctor or any healthcare provider to urgently stop the extreme abnormal condition until the results come back normal or near of it.

Other codes in the lab test report

Flag A, Flag L on platelets, Flag H on platelets, and reddish double arrows and star marks, but I will explain that later in another post, so that please follow and save this website to be alert when there is another explanation, also you may send your results to get free interpretation.

the flag A prior a test result

What is The Meaning of Flag A Near Some Blood Test Results? (WBC, RBC, PLT, Hgb, MCV, RDW, Glucose, BhCG)

Medical laboratories take a distinct approach to organize the writing of medical reports in a way that ensures easy reading and maximize the benefits from the laboratory results. Among the ways to facilitate writing and reading the laboratory reports are abbreviations that make the medical report understandable with the least amount of writing.

We have discussed before the meaning of the letter “L” before platelets, you can understand it from here; understand the Flag L on Platelets.
We have discussed before the significance of the letter “H” before the result of platelets, from here we can understand the meaning of “H” on platelets.

And here, we clarify the meaning of the mark ” A ” that is placed near the test result and sometimes placed before any result.

you may know that the flag or the mark is used in order to draw the attention of the reader of the laboratory report that there is a difference in this result to be flagged from the rest of the results written in the final report. And if the result is normal, it is not necessary to put a distinctive sign such as the letter “ A ” before the number that expresses the result of your test . But if the result is abnormal, some medical reports distinguish it by adding the letter “ A ” next to the result that is outside the human healthy level to alarm the reader “it’s an Abnormal result”.

The image below educate you how to read the CBC test report that include some results flagged with the letter “A” as an example.

What is the meaning of flag A prior a test result
Example: demonstration the flag “A” near the CBC lab test results

Which test results that should be marked with the letter “A” ?

Did you know before how the laboratory report is written? the lab result consists of three pieces , the first on the left of the report is the name of the test that was done, the second in the middle is dedicated to the result that appeared when doing the test, and the third is used to write down the normal levels that the patient’s result must correspond with so that we can say that the test result is normal and don’t represent an issue .

Therefore, any result that is not within this known normal range, a distinctive mark must be placed near it for easy identification.

If you want to know what is the meaning of abnormal labs, you may go here, Understand the Abnormal Lab Results.

Which lab test should flagged by “A”?

Examples of tests that the laboratory puts a distinction “ A ” next to it:

  • Total white blood count test (WBC or TLC) , tells us how many white blood cells are circulating in the bloodstream , if the number is greater than the highest normal number for a human being it’s called leukocytosis , and if the number is less than it’s called leukocytopenia or leucopenia, both conditions are considered an abnormal WBC result and must be flagged by the notation “ A ” accompanying the number of the result.
  • Test of the red blood cell count “RBCs” , when the number that was measured in the laboratory is within the normal range for each age, it means that there is no problem with the red blood cells count , but if the number of red blood cells for the patient’s sample is less ( Erythropenia ) or higher ( polycythemia ) than normal levels Specific for each age, the medical report flagging the result by adding the mark “ A ” to the number.

Examples of lab that may not got the notation “A” sign near the result?

  • Quantitative pregnancy test or BhCG test : This test does not have a normal range, as the goal of the test is to know the gestation days and viability of the new fetus in the mother’s womb, and therefore the resulting number after doing the test is not described as being normal or abnormal in the first place , and therefore it does not the result that must be marked with such signs that aim to show results that are inconsistent with the healthy range . There is a full page that explains about the letters used to distinguish the result of a quantitative pregnancy test. Provide your information about it there .

Which are abnormal results that don’t flagged by “A”?

Examples of abnormal test results, but the distinctive abnormal mark “A” is not shown around them:

  • The infectious viruses such as C virus, B virus and AIDS virus : The presence of the virus in a blood sample is expressed by the word “ Positive”, and therefore, the result may accompanied by a flag sign near it to confirm that the patient is infected with the virus, but sometimes has a different sign ” a star or an asterisk”, a star-shaped character (*) similar to that used in some books to indicate a cross-reference to a footnote, this sign” is a substitute to the flags of the type “letter” when the result isn’t in numbers .

Here we tried to write down the most common labs that are performed and reported with flag or alert of the type “A” and to clarify the importance of the distinction that the laboratory makes about your lab results, but if you want more clarification on how to read your own results, please do not hesitate to write to us or send a message that includes pictures of the labs and we promise you a brief useful explanation of your lab report.

Abstract : The letter “ A ” is an abbreviation of the word “ Abnormal ” and is used as a alerting sign to the right of or around the lab result that is written in numbers, in order to warn or attract attention that this number resulting from the test of your blood is outside the normal permissible range defined for the human healthy condition in similar age and gender. This method of recognizing the exceeded results helps in speeding up the reading of the test and enhances your understanding of the labs and what’re the possible steps you should do after receiving the test and here you find the detailed description and other examples of the tests flagged with the letter “ A ”.

That was how to read the lab test report that has the flag “A”, however, lab test results may include some mysterious characters and signs that you may not know about, so that feel free to post your question or messaging us through comments or Facebook page and group, however, you may follow this website for future explanation that may educate you to read and understand your lab results easily.