Erythrocyte Sedimentation Rate (ESR)
Why Get Tested?
To detect the presence of inflammation caused by one or more conditions such as infections, tumors or autoimmune diseases; to help diagnose and monitor specific conditions such as temporal arteritis, systemic vasculitis, polymyalgia rheumatica, or rheumatoid arthritis
When To Get Tested?
When your health practitioner thinks that you might have a condition causing inflammation; when you have signs and symptoms associated with temporal arteritis, systemic vasculitis, polymyalgia rheumatica, or rheumatoid arthritis such as headaches, neck or shoulder pain, pelvic pain, anemia, poor appetite, unexplained weight loss, and joint stiffness
HbA1C
Why Get Tested?
To help determine whether you are at an increased risk of developing diabetes; to help diagnose diabetes and prediabetes; to monitor diabetes and to aid in treatment decisions
When To Get Tested?
As part of a health checkup or when you have risk factors for or symptoms of diabetes; after first diagnosis with diabetes, every 3-4 months or about 120 days to ensure that your glycemic goals are met and/or maintained or when your therapy plan has changed 
Calcium
When To Get Tested?
As part of a routine metabolic panel; when you have symptoms of a disorder, or known presence of one, affecting your kidneys, bones, thyroid, parathyroid, or nerves or when symptoms of significantly increased or decreased calcium concentrations are present; when someone is critically ill, to monitor ionized calcium levels; when someone has certain types of cancer; when someone is being treated for abnormal calcium levels, to evaluate the effectiveness of treatment
Vitamin B12
Why Get Tested?
To help diagnose one cause of anemia or neuropathy; to evaluate nutritional status in some people; to monitor the effectiveness of treatment for vitamin B12 or folate deficiency
When To Get Tested?
When you have abnormal results on a complete blood count (CBC) with a blood smear showing large red blood cells (macrocytosis) or abnormal (hypersegmented) neutrophils; when you have symptoms of anemia (weakness, tiredness, pale skin) and/or of neuropathy (tingling or itching sensations, eye twitching, memory loss, altered mental status); when you are being treated for vitamin B12 or folate deficiency\
Lipid Profile
Why Get Tested?
To assess your risk of developing cardiovascular disease (CVD); to monitor treatment of unhealthy lipid levels
When To Get Tested?
Screening when no risk factors present: for adults, every four to six years; for children, teens and young adults, once between the ages of 9 and 11 and again between ages 17 and 21
Monitoring: at regular intervals when you have risk factors, when prior results showed high risk levels, and/or to monitor effectiveness of treatment
When is it ordered?
Adults with no other risk factors for heart disease should be tested with a fasting lipid panel once every four to six years.
If you have risk factors or if previous testing showed that you had a high cholesterol level, more frequent testing with a full lipid panel is recommended.
Examples of risk factors other than high LDL-C include:
Cigarette smoking
Being overweight or obese
Unhealthy diet
Being physically inactive—not getting enough exercise
Age (if you are a male 45 years or older or a female 50-55 years or older)
Hypertension (blood pressure of 140/90 or higher or taking high blood pressure medications)
Family history of premature heart disease (heart disease in a first-degree male relative under age 55 or a first-degree female relative under age 65)
Pre-existing heart disease or already having had a heart attack
Diabetes or prediabetes
Children, teens, and young adults (ages 2 to 24 years old) with no risk factors should have a lipid panel once between the ages of 9 and 11 and again between 17 and 21, according to the American Academy of Pediatrics (AAP).
Children, teens, and young adults with an increased risk of developing heart disease as adults should have earlier and more frequent screening with lipid panels. Some of the risk factors are similar to those in adults and include a family history of heart disease or health problems such as diabetes, high blood pressure, or being overweight. High-risk children should be tested between 2 and 8 years old with a fasting lipid panel, according to the AAP.
Children younger than 2 years old are too young to be tested.
For additional details on this, see the screening articles for Children, Teens, Young Adults, Adults, and Adults 50 and Up.
Monitoring
A lipid panel may be ordered at regular intervals to evaluate the success of lipid-lowering lifestyle changes such as diet and exercise or to determine the effectiveness of medication such as statins.
Thyroid Profile
Why Get Tested?
To help evaluate thyroid gland function and to help diagnose thyroid disorders; to monitor treatment of thyroid disorders
When To Get Tested?
When you have signs and symptoms suggesting underactive thyroid (hypothyroidism) or overactive thyroid (hyperthyroidism) due to a condition affecting the thyroid; when you have an enlarged thyroid (goiter) or a thyroid nodule (a small lump on the thyroid gland that may be solid or a fluid-filled cyst)
When is it ordered?
A thyroid panel may be ordered when you have signs and symptoms that suggest underactive thyroid (hypothyroidism) or overactive thyroid (hyperthyroidism) due to a thyroid disorder.
Signs and symptoms of an underactive thyroid may include:
Slowed heart rate
Weight gain
Enlarged thyroid (goiter)
Dry skin
Constipation
Trouble tolerating cold
Muscle and joint pain
Puffy skin
Thinning hair, hair loss
Fatigue
Depression
Forgetfulness
Heavy or irregular menstrual periods or infertility in women
Signs and symptoms of an overactive thyroid may include:
Rapid heart rate
Anxiety
Weight loss
Difficulty sleeping
Tremors in the hands
Muscle weakness
Increased sweating
Trouble tolerating heat
Sometimes more frequent bowel movements
Some uncommon problems that can affect the eyes: puffiness around the eyes, dryness, irritation, excessive tearing, light sensitivity, blurry double vision
In some cases, bulging of the eyes
Less frequent or lighter menstrual periods in women