Reference ranges for blood tests explained

Reference ranges (reference intervals) for blood tests are sets of values used by a health professional to interpret a set of medical test results from blood samples. Reference ranges for blood tests are studied within the field of clinical chemistry (also known as "clinical biochemistry", "chemical pathology" or "pure blood chemistry"), the area of pathology that is generally concerned with analysis of bodily fluids.

Blood test results should always be interpreted using the reference range provided by the laboratory that performed the test.^[1]

Interpretation

A reference range is usually defined as the set of values 95 percent of the normal population falls within (that is, 95% prediction interval).^[2] It is determined by collecting data from vast numbers of laboratory tests.

Plasma or whole blood

In this article, all values (except the ones listed below) denote blood plasma concentration, which is approximately 60–100% larger than the actual blood concentration if the amount inside red blood cells (RBCs) is negligible. The precise factor depends on hematocrit as well as amount inside RBCs. Exceptions are mainly those values that denote total blood concentration, and in this article they are:^[3]

• All values in Hematology – red blood cells (except hemoglobin in plasma)
• All values in Hematology – white blood cells
• Platelet count (Plt)

A few values are for inside red blood cells only:

• Vitamin B₉ (folic acid/folate) in red blood cells
• Mean corpuscular hemoglobin concentration (MCHC)

Units

• Mass concentration (g/dL or g/L) is the most common measurement unit in the United States. Is usually given with dL (decilitres) as the denominator in the United States, and usually with L (litres) in, for example, Sweden.
• Molar concentration (mol/L) is used to a higher degree in most of the rest of the world, including the United Kingdom and other parts of Europe and Australia and New Zealand.^[4]
• International units (IU) are based on measured biological activity or effect, or for some substances, a specified equivalent mass.
• Enzyme activity (kat) is commonly used for e.g. liver function tests like AST, ALT, LD and γ-GT in Sweden.
• Percentages and time-dependent units (mol/s) are used for calculated derived parameters, e.g. for beta cell function in homeostasis model assessment or thyroid's secretory capacity.

Arterial or venous

If not otherwise specified, a reference range for a blood test is generally the venous range, as the standard process of obtaining a sample is by venipuncture. An exception is for acid–base and blood gases, which are generally given for arterial blood.

Still, the blood values are approximately equal between the arterial and venous sides for most substances, with the exception of acid–base, blood gases and drugs (used in therapeutic drug monitoring (TDM) assays).^[5] Arterial levels for drugs are generally higher than venous levels because of extraction while passing through tissues.^[5]

Usual or optimal

Reference ranges are usually given as what are the usual (or normal) values found in the population, more specifically the prediction interval that 95% of the population fall into. This may also be called standard range. In contrast, optimal (health) range or therapeutic target is a reference range or limit that is based on concentrations or levels that are associated with optimal health or minimal risk of related complications and diseases. For most substances presented, the optimal levels are the ones normally found in the population as well. More specifically, optimal levels are generally close to a central tendency of the values found in the population. However, usual and optimal levels may differ substantially, most notably among vitamins and blood lipids, so these tables give limits on both standard and optimal (or target) ranges. In addition, some values, including troponin I and brain natriuretic peptide, are given as the estimated appropriate cutoffs to distinguish healthy people from people with specific conditions, which here are myocardial infarction and congestive heart failure, respectively, for the aforementioned substances.

Variability

References range may vary with age, sex, race, pregnancy,^[6] diet, use of prescribed or herbal drugs and stress. Reference ranges often depend on the analytical method used, for reasons such as inaccuracy, lack of standardisation, lack of certified reference material and differing antibody reactivity.^[7] Also, reference ranges may be inaccurate when the reference groups used to establish the ranges are small.^[8]

Sorted by concentration

By mass and molarity

Smaller, narrower boxes indicate a more tight homeostatic regulation when measured as standard "usual" reference range.

Hormones predominate at the left part of the scale, shown with a red at ng/L or pmol/L, being in very low concentration. There appears to be the greatest cluster of substances in the yellow part (μg/L or nmol/L), becoming sparser in the green part (mg/L or μmol/L). However, there is another cluster containing many metabolic substances like cholesterol and glucose at the limit with the blue part (g/L or mmol/L).

The unit conversions of substance concentrations from the molar to the mass concentration scale above are made as follows:

• Numerically:

molarconcentration x molarmass = massconcentration

• Measured directly in distance on the scales:

log _{10} (molarmass)/(1000) = distancetoright(decades) ,where distance is the direct (not logarithmic) distance in number of decades or "octaves" to the right the mass concentration is found. To translate from mass to molar concentration, the dividend (molar mass and the divisor (1000) in the division change places, or, alternatively, distance to right is changed to distance to left. Substances with a molar mass around 1000g/mol (e.g. thyroxine) are almost vertically aligned in the mass and molar images. Adrenocorticotropic hormone, on the other hand, with a molar mass of 4540,^[9] is 0.7 decades to the right in the mass image. Substances with molar mass below 1000g/mol (e.g. electrolytes and metabolites) would have "negative" distance, that is, masses deviating to the left.Many substances given in mass concentration are not given in molar amount because they haven't been added to the article.

The diagram above can also be used as an alternative way to convert any substance concentration (not only the normal or optimal ones) from molar to mass units and vice versa for those substances appearing in both scales, by measuring how much they are horizontally displaced from one another (representing the molar mass for that substance), and using the same distance from the concentration to be converted to determine the equivalent concentration in terms of the other unit. For example, on a certain monitor, the horizontal distance between the upper limits for parathyroid hormone in pmol/L and pg/mL may be 7 cm, with the mass concentration to the right. A molar concentration of, for example, 5 pmol/L would therefore correspond to a mass concentration located 7 cm to the right in the mass diagram, that is, approximately 45 pg/mL.

By units

Units do not necessarily imply anything about molarity or mass.

A few substances are below this main interval, e.g. thyroid stimulating hormone, being measured in mU/L, or above, like rheumatoid factor and CA19-9, being measured in U/mL.

White blood cells

Sorted by category

Ions and trace metals

Included here are also related binding proteins, like ferritin and transferrin for iron, and ceruloplasmin for copper.

Test	Lower limit	Upper limit	Unit*	Comments	-	Sodium (Na)	135, 137	145, 147	mmol/L or mEq/L		-	310,^[10] 320	330, 340	mg/dL	-	-	Potassium (K)	3.5, 3.6	5.0, 5.1	mmol/L or mEq/L		-	14^[11]	20	mg/dL	-	-	Chloride (Cl)	95, 98, 100	105, 106, 110	mmol/L or mEq/L		-	340^[12]	370	mg/dL	-	-	Ionized calcium (Ca)	1.03,^[13] 1.10	1.23, 1.30	mmol/L		-	-	4.1,^[14] 4.4	4.9, 5.2	mg/dL	-	-	Total calcium (Ca)	2.1,^[15] 2.2	2.5, 2.6, 2.8	mmol/L		-	-	8.4, 8.5	10.2, 10.5	mg/dL		-	-	Total serum iron (TSI) – male	65,^[16] 76	176, 198	μg/dL		-	11.6,^[17] 13.6	30, 32, 35	μmol/L	-	-	Total serum iron (TSI) – female	26, 50	170	μg/dL		-	-	4.6, 8.9	30.4	μmol/L		-	-		100	250	μg/dL		-	-	18^[18]	45	μmol/L		-	-	Total serum iron (TSI) – children	50	120	μg/dL		-	-	9	21	μmol/L		-	-	Total iron-binding capacity (TIBC)	240, 262	450, 474	μg/dL		-	-	43, 47	81, 85	μmol/L		-	-		190,^[19] 194, 204	326, 330, 360	mg/dL		-	25^[20]	45	μmol/L		-	-		20	50	%		-	Ferritin – Males and postmenopausal females	12^[21]	300^[22]	ng/mL or μg/L		-	27^[23]	670	pmol/L		-	-	Ferritin – premenopausal females	12	150 – 200	ng/mL or μg/L		-	27	330 – 440	pmol/L		-	-		10,^[24] 20^[25]	35, 65	μmol/L		-	17,^[26] 34	60, 110	μg/dL	-	Copper (Cu)	70	150	μg/dL		-	11^[27]	24	μmol/L	-		15	60	mg/dL		-	1^[28]	4	μmol/L		-	Phosphate (HPO4^2−)	0.8	1.5^[29]	mmol/L		-	-	Inorganic phosphorus (serum)	1.0	1.5	mmol/L	-	3.0	4.5	mg/dL		-	-	Zinc (Zn)	60,^[30] 72^[31]	110, 130	μg/dL		-	9.2,^[32] 11	17, 20	μmol/L	-		1.5, 1.7^[33]	2.0, 2.3	mEq/L or mg/dL		-	0.6,^[34] 0.7	0.82, 0.95	mmol/L	-

• Note: Although 'mEq' for mass and 'mEq/L' are sometimes used in the United States and elsewhere, they are not part of SI and are now considered redundant.

Acid–base and blood gases

If arterial/venous is not specified for an acid–base or blood gas value, then it generally refers to arterial, and not venous which otherwise is standard for other blood tests.

Acid–base and blood gases are among the few blood constituents that exhibit substantial difference between arterial and venous values.^[5] Still, pH, bicarbonate and base excess show a high level of inter-method reliability between arterial and venous tests, so arterial and venous values are roughly equivalent for these.^[35]

Test	Arterial/Venous	Lower limit	Upper limit	Unit	-		Arterial	7.34, 7.35	7.44, 7.45		-	Venous	7.31^[36]	7.41		-	-	[H^+] || rowspan=2|Arterial || 36 || 44 || nmol/L |- | 3.6^[37] || 4.4 || ng/dL |- | Base excess || Arterial & venous || −3 || +3 || mEq/L |- |rowspan=4| Oxygen partial pressure (pO2) ||rowspan=2| Arterial pO2 || 10, 11 || 13, 14 || kPa |- | 75, 83 || 100, 105 || mmHg or torr |- |rowspan=2| Venous || 4.0 || 5.3 || kPa |- | 30 || 40 || mmHg or torr |- |rowspan=2| Oxygen saturation || Arterial || 94, 95,^[38] 96 || 100 ||rowspan=2| % |- | Venous || colspan=2| Approximately 75 |- |rowspan=4| Carbon dioxide partial pressure (pCO2) ||rowspan=2| Arterial PaCO2 || 4.4, 4.7^[39] || 5.9, 6.0 || kPa |- | 33, 35 || 44, 45 || mmHg or torr |- |rowspan=2| Venous || 5.5, || 6.8 || kPa |- | 41 || 51 || mmHg or torr |- |rowspan=2| Absolute content of carbon dioxide (CO2) ||rowspan=2| Arterial || 23 || 30 || mmol/L |- | 100^[40] || 132 || mg/dL |- |rowspan=2| Bicarbonate (HCO3^−) || rowspan=2| Arterial & venous || 18^[41] || 23 || mmol/L |- | 110^[42] || 140 || mg/dL |- |rowspan=2| Standard bicarbonate (SBCe) || rowspan=2| Arterial & venous || 21, 22 || 27, 28 || mmol/L or mEq/L |- | 134 || 170 || mg/dL |-|} Liver function Test Patient type Lower limit Upper limit Unit Comments - Total protein (TotPro) 60, 63 78, 82, 84 g/L - 35 48, 55 g/L - 3.5 4.8, 5.5 U/L - 540^[43] 740 μmol/L - 23 35 g/L - 1.7,^[44] 2, 3.4, 5 17, 22, 25 μmol/L - 0.1, 0.2, 0.29 1.0, 1.3, 1.4^[45] mg/dL - Direct/conjugated bilirubin 0.0 or N/A 5, 7 μmol/L - 0 0.3, 0.4 mg/dL - Alanine transaminase (ALT/ALAT) 5, 7, 8^[46] 20, 21, 56 U/L Also called serum glutamic pyruvic transaminase (SGPT) - Female 0.15 0.75 μkat/L - Male 0.15 1.1 - Aspartate transaminase (AST/ASAT) Female 6^[47] 34 IU/L Also called serum glutamic oxaloacetic transaminase (SGOT) - 0.25 0.60 μkat/L - Male 8 40 IU/L - 0.25 0.75 μkat/L - Alkaline phosphatase (ALP) 0.6 1.8 μkat/L - Female 42^[48] 98 U/L - Male 53 128 - Gamma glutamyl transferase (GGT) 5, 8 40, 78 U/L - Female 0.63^[49] μkat/L - Male 0.92 μkat/L - Cardiac tests Test Patient type Lower limit Upper limit Unit Comments - Creatine kinase (CK) Male 24, 38, 60 174, 320 U/L or ng/mL - 0.42^[50] 1.5 μkat/L - Female 24, 38, 96 140, 200 U/L or ng/mL - 0.17 1.17 μkat/L - 0 3, 3.8, 5 ng/mL or μg/L - Female 1^[51] 66 ng/mL or μg/L - Male 17 106 - Cardiac troponin T (low sensitive) 0.1^[52] ng/mL 99th percentile cutoff Cardiac troponin I(high sensitive) 0.03 ng/mL 99th percentile cutoff Cardiac troponin T (high sensitive) Male 0.022 ng/mL 99th percentile cutoff Female 0.014 ng/mL 99th percentile cutoff newborn/infants not established more than adults ^[53] ^[54] Brain natriuretic peptide (BNP) Interpretation Range / Cutoff Congestive heart failure unlikely < 100 pg/mL^[55] ^[56] "Gray zone" 100–500 pg/mL Congestive heart failure likely > 500 pg/mL NT-proBNP Interpretation Age Cutoff Congestive heart failure likely < 75 years > 125 pg/mL^[57] > 75 years > 450pg/mL Lipids Test Patient type Lower limit Upper limit Unit - Triglycerides 10–39 years 54 110 mg/dL < 100 mg/dL or 1.1 mmol/L - 0.61^[58] 1.2 mmol/L - 40–59 years 70 150 mg/dL - 0.77 1.7 mmol/L - > 60 years 80 150 mg/dL - 0.9 1.7 mmol/L - 3.0,^[59] 3.6 5.0, 6.5 mmol/L < 3.9 mmol/L - 120, 140 200, 250 mg/dL < 150 mg/dL - Female 1.0,^[60] 1.2, 1.3 2.2 mmol/L > 1.0 or 1.6 mmol/L 40 or 60^[61]  mg/dL - 40,^[62] 50^[63] 86 mg/dL - HDL cholesterol Male 0.9 2.0 mmol/L - 35 80 mg/dL - LDL cholesterol (Not valid when triglycerides >5.0 mmol/L) 2.0, 2.4 3.0, 3.4 mmol/L < 2.5 mmol/L - 80, 94 120, 130 mg/dL < 100 mg/dL - LDL/HDL quotient n/a 5 (unitless) Tumour markers Test Patient type Cutoff Unit Comments - Alpha fetoprotein (AFP) 44 ng/mL or μg/L Hepatocellular carcinoma or testicular cancer - Beta human chorionic gonadotrophin (β-hCG) In males and non-pregnant females 5 IU/L or mU/mL choriocarcinoma - 40 U/mL Pancreatic cancer - 30,^[64] 35^[65] kU/L or U/mL - Carcinoembryonic antigen (CEA) Non-smokers, 50 years 3.4, 3.6^[66] μg/L - Non-smokers, 70 years 4.1 - Smokers 5^[67] - Prostate specific antigen (PSA) 40–49 years 1.2–2.9^[68] μg/L or ng/mL - 4.0–9.0 - 70–79 years, African-American 7.7–13 - 3 units/dL (Bodansky units) - 5,^[69] 15 ng/L or pg/mL Cutoff against medullary thyroid cancer More detailed cutoffs in Calcitonin article Endocrinology Thyroid hormones Test Patient type Lower limit Upper limit Unit - Thyroid stimulating hormone (TSH or thyrotropin) 0.3, 0.4, 0.5, 0.6^[70] 4.0, 4.5, 6.0 mIU/L or μIU/mL - 0.3,^[71] 0.5^[72]	2.0, 3.0	-	Infants	1.3^[73]	19	-	Free thyroxine (FT4)	Normal adult	0.7,^[74] 0.8	1.4, 1.5, 1.8^[75]	ng/dL	-	9, 10, 12^[76]	18,^[77] 23	pmol/L	-	Child/Adolescent 31 d – 18 y	0.8	2.0	ng/dL	-	10	26	pmol/L	-	Pregnant	0.5	1.0	ng/dL	-	6.5	13	pmol/L	-	Total thyroxine		4, 5.5	11, 12.3	μg/dL	-	60	140, 160	nmol/L	-	Free triiodothyronine (FT3)	Normal adult	0.2	0.5	ng/dL	-	3.1^[78]	7.7	pmol/L	-	Children 2-16 y	0.1^[79]	0.6	ng/dL	-	1.5	9.2	pmol/L	-			60, 75^[80]	175, 181	ng/dL	-	0.9, 1.1	2.5, 2.7	nmol/L	-	Thyroxine-binding globulin (TBG)		12	30	mg/L	-	Thyroglobulin (Tg)		1.5	30	pmol/L	-	1	20	μg/L	-

Sex hormones

The diagrams below take inter-cycle and inter-woman variability into account in displaying reference ranges for estradiol, progesterone, FSH and LH.

Other hormones

Test	Patient type	Lower limit	Upper limit	Unit	-	Adrenocorticotropic hormone (ACTH)		2.2^[99]	13.3	pmol/L	-	20	100	pg/mL	-			140^[100]	700	nmol/L	-	5^[101]	25	μg/dL	-	Midnight	80	350	nmol/L	-	2.9	13	μg/dL	-	Growth hormone (fasting)		0	5	ng/mL	-	Growth hormone (arginine stimulation)		7	n/a	ng/mL	-	IGF-1	Female, 20 yrs	110^[102]	420	ng/mL	-	Female, 75 yrs	55	220	-	Male, 20 yrs	160	390	-	Male, 75 yrs	48	200	-	Prolactin	Female	71, 105	348, 548^[103]	mIU/L	-	3.4, 3.9	16.4, 20.3	μg/L	-	Male	58, 89	277, 365	mIU/L	-	2.7, 3.3	13.0, 13.5	μg/L	-	Parathyroid hormone (PTH)		10,^[104] 17^[105]	65, 70	pg/mL	-		1.1, 1.8^[106]	6.9, 7.5	pmol/L	-			8,^[107] 9	40, 80	ng/mL	-	20,^[108] 23^[109]	95, 150	nmol/L	-			30,^[110] 40^[111]	65, 100	ng/mL	-	85,^[112] 100	120, 160	nmol/L	-			0.29,^[113] 1.9	3.7^[114]	ng/(mL·h)
	3.3,^[115] 21^[116]	41	mcU/mL	-	Aldosterone			Adult		19, 34.0	ng/dL	-		530, 940^[117]	pmol/L			-	Aldosterone-to-renin ratio	Adult		13.1, 35.0^[118]	ng/dL per ng/(mL·h)	-			360, 970	pmol/liter per μg/(L·h)

Vitamins

Also including the vitamin B₁₂)-related amino acid homocysteine.

Test	Patient type	Standard range		Optimal range		Unit	-	Lower limit	Upper limit	Lower limit	Upper limit	-			30	65			μg/dL	-	Vitamin B9 (Folic acid/Folate) – Serum	Age > 1 year	3.0^[119]	16	5^[120]		ng/mL or μg/L	-	6.8^[121]	36	11		nmol/L	-	Vitamin B9 (Folic acid/Folate) – Red blood cells		200	600			ng/mL or μg/L	-		450	1400			nmol/L	-	Pregnant			400		ng/mL or μg/L	-			900		nmol/L	-	Vitamin B12 (Cobalamin)		130,^[122] 160^[123]	700, 950			ng/L	-		100,^[124] 120	520, 700			pmol/L	-	Homocysteine		3.3,^[125] 5.9	7.2, 15.3		6.3	μmol/L	-		45,^[126] 80	100, 210		85	μg/dL	-	Vitamin C (Ascorbic acid)		0.4	1.5	0.9		mg/dL	-	23^[127]	85	50		μmol/L	-	25-hydroxycholecalciferol (a vitamin D)		8, 9	40, 80	30, 40	65, 100	ng/mL	-	20, 23	95, 150	85, 100	120, 160	nmol/L	-					28		μmol/L	-			1.2		mg/dL	-

Toxic Substances

Test	Limit type	Limit	Unit	-			< 20 or 40	μg/dL	-			0, 0.2,^[128] 0.8	‰ or g/L	-	17.4^[129]	mmol/L

Hematology

Red blood cells

These values (except Hemoglobin in plasma) are for total blood and not only blood plasma.

Test	Patient	Lower limit	Upper limit	Unit	Comments	-	Hemoglobin (Hb)	Male	2.0,^[130] 2.1^[131]	2.5, 2.7	mmol/L	Higher in neonates, lower in children.	-	130, 132, 135	162, 170, 175	g/L	-	Female	1.8, 1.9	2.3, 2.5	mmol/L	Sex difference negligible until adulthood.	-	120^[132]	150, 152, 160	g/L	-	Hemoglobin subunits (sometimes displayed simply as "Hemoglobin")	Male	8.0,^[133] 8.4	10.0, 10.8	mmol/L	4 per hemoglobin molecule	-	Female	7.2, 7.6	9.2, 10.0	-	Hemoglobin in plasma		0.16	0.62	μmol/L	Normally diminutive compared with inside red blood cells	-		1	4	mg/dL	-	Glycated hemoglobin (HbA1c)	< 50 years	3.6	5.0	% of Hb		-	> 50 years	3.9	5.3	-		< 50 years	0.35	1.9	g/L		-	> 50 years	0.47	2.1	-	Hematocrit (Hct)	Male	0.39, 0.4, 0.41, 0.45	0.50, 0.52, 0.53, 0.62	L/L		-	Female	0.35, 0.36, 0.37	0.46, 0.48	L/L		-	Child	0.31	0.43	L/L		-	Mean corpuscular volume (MCV)	Male	76, 82	100, 102	fL	Cells are larger in neonates, though smaller in other children.	-	Female	78	101	fL	-	Red blood cell distribution width (RDW)		11.5	14.5	%		-	Mean cell hemoglobin (MCH)		0.39	0.54	fmol/cell		-	25, 27	32, 33, 35	pg/cell	-	Mean corpuscular hemoglobin concentration (MCHC)		4.8,^[134] 5.0	5.4, 5.6	mmol/L		-		31, 32	35, 36	g/dL or %	-	Erythrocytes/Red blood cells (RBC)	Male	4.2, 4.3	5.7, 5.9, 6.2, 6.9	x10^12/L or million/mm^3		-	Female	3.5, 3.8, 3.9	5.1, 5.5		-	Infant/Child	3.8	5.5		-	Reticulocytes	Adult	26	130	x10^9/L		-	0.5	1.5	% of RBC		-	Newborn	1.1	4.5	% of RBC		-	Infant	0.5	3.1	% of RBC		-	Immature reticulocyte fraction (IRF)	Adult	1.6^[135]	12.1	% of reticulocytes		-	Reticulocyte hemoglobin equivalent	Adult	30.0	37.6	%		-	24.1^[136]	35.8	pg	-	Immature platelet fraction (IPF)	Adult	0.8	5.6	%

White blood cells

These values are for total blood and not only blood plasma.

Test	Patient type	Lower limit	Upper limit	Unit	-	Rowspan=3	White Blood Cell Count (WBC)	Adult	3.5, 3.9,^[137] 4.1, 4.5	9.0, 10.0, 10.9, 11	x10^9/L x10^3/mm^3 or x10^3/μL	-	Newborn	9^[138]	30	-	1 year old	6	18	-	Neutrophil granulocytes (A.K.A. grans, polys, PMNs, or segs)	Adult	1.3, 1.8, 2	5.4, 7, 8	x10^9/L	-	45–54	62, 74	% of WBC	-	Newborn	6	26	x10^9/L	-		Adult		0.7	x10^9/L	-	3	5	% of WBC	-	Lymphocytes	Adult	0.7, 1.0	3.5, 3.9, 4.8	x10^9/L	-	16–25	33, 45	% of WBC	-	Newborn	2	11	x10^9/L	-	Monocytes	Adult	0.1, 0.2^[139] ^[140]	0.8	x10^9/L	-	3, 4.0	7, 10	% of WBC	-	Newborn	0.4	3.1	x10^9/L	-	Mononuclear leukocytes (Lymphocytes + monocytes)	Adult	1.5	5	x10^9/L	-	20	35	% of WBC	-		Adult	0.4,^[141] 0.5	1.5, 1.8	x10^9/L	-	Eosinophil granulocytes	Adult	0.0, 0.04	0.44, 0.45, 0.5	x10^9/L	-	1	3, 7	% of WBC	-	Newborn	0.02	0.85	x10^9/L	-	Basophil granulocytes	Adult	40	100, 200, 900	x10^6/L	-	0.0	0.75, 2	% of WBC	-	Newborn		0.64	x10^9/L

Coagulation

Test	Lower limit	Upper limit	Unit	Comments	-	Thrombocyte/Platelet count (Plt)	140, 150	350, 400, 450	x10^9/L or x1000/μL		-	Mean platelet volume (MPV)	7.2,^[142] 7.4,^[143] 7.5^[144]	10.4, 11.5, 11.7			-	Prothrombin time (PT)	10, 11, 12	13, 13.5, 14, 15	s	PT reference varies between laboratory kits – INR is standardised	-	INR	0.9	1.2		The INR is a corrected ratio of a patient's PT to normal	-	Activated partial thromboplastin time (APTT)	18, 30	28, 42, 45	s		-	Thrombin clotting time (TCT)	11	18	s		-		1.7, 2.0	3.6, 4.2	g/L		-		0.80	1.2	kIU/L		-	0.15, 0.17^[145]	0.2, 0.39	mg/mL	-		2	9	minutes		-	Viscosity	1.5^[146]	1.72

Immunology

Acute phase proteins

Acute phase proteins are markers of inflammation.

Test	Patient	Lower limit	Upper limit	Unit	Comments	-	Erythrocyte sedimentation rate (ESR)	Male	0	Age÷2	mm/h	ESR increases with age and tends to be higher in females.^[147]	-	Female	(Age+10)÷2^[148]	-	C-reactive protein (CRP)			5, 6^[149]	mg/L		-		200, 240	nmol/L	-	Alpha 1-antitrypsin (AAT)		20,^[150] 22^[151]	38, 53	μmol/L		-		89,^[152] 97	170, 230	mg/dL		-				0.15^[153]	ng/mL or μg/L

Isotypes of antibodies

Test	Patient	Lower limit	Upper limit	Unit	-		Adult	70, 110^[154]	360, 560	mg/dL	-		0.5	3.0	-		0.01	0.04	-		800	1800	-		54	220	-

Autoantibodies

Autoantibodies are usually absent or very low, so instead of being given in standard reference ranges, the values usually denote where they are said to be present, or whether the test is a positive test. There may also be an equivocal interval, where it is uncertain whether there is a significantly increased level.

Test	Negative	Equivocal	Positive	Unit	-	anti-SS-A (Ro)	< 1.0^[155]	n/a	≥ 1.0	Units (U)	-	anti-SS-B (La)	< 1.0^[156]	n/a	≥ 1.0	-		< 30.0^[157]	30.0–75.0	> 75.0	International Units per millilitre (IU/mL)	-		< 8^[158]	8–10	> 10	Units per millilitre (U/mL)	-		< 25	n/a	> 25	-	Cytoplasmic anti-neutrophil cytoplasmic antibodies (c-ANCA)	< 20	21–30	> 30	-	Perinuclear anti-neutrophil cytoplasmic antibodies (p-ANCA)	< 5	n/a	> 5	-	Anti-mitochondrial antibodies (AMA)	< 0.1^[159]	0.1-0.9	≥ 1.0	Units (U)	-	Rheumatoid factor (RF)	< 20	20–30	> 30	Units per millilitre (U/mL)	-	Antistreptolysin O titre (ASOT) in preschoolers			> 100	-	ASOT at school age	> 250	-	ASOT in adults	> 125

Test	Negative	Low/weak positive	Moderate positive	High/strong positive	Unit	-	Anti-phospholipid IgG	< 20	20–30	31–50	> 51	GPLU/mL	-	Anti-phospholipid IgM	< 1.5	1.5–2.5	2–9.9	> 10	MPL /mL	-	Anti-phospholipid IgA	< 10	10–20	21–30	> 31	arb U/mL	-		< 20	20–39	40–59	> 60	EU

Other immunology

Test	Lower limit	Upper limit	Unit	-	Serum free light chains (FLC): kappa/lambda ratio	0.26^[160]	1.65	(unitless)

Other enzymes and proteins

Test	Lower limit	Upper limit	Unit	Comments	-		60, 63	78, 82, 84	g/L		-	Lactate dehydrogenase (LDH)	50	150	U/L		-	0.4	1.7	μmol/L		-	1.8	3.4	μkat/L	< 70 years old	-		25, 30, 53	110, 120, 123, 125, 190	U/L		-	0.15	1.1	μkat/L		-	200^[161]	240	nmol/L		-	D-dimer	n/a	500^[162]	ng/mL	Higher in pregnant women^[163]	-	0.5	mg/L	-		7, 10, 23	60, 150, 208	U/L		-	Angiotensin-converting enzyme (ACE)	23	57	U/L		-			3.0	ng/mL		-	Eosinophil cationic protein (ECP)	2.3	16	μg/L

Other electrolytes and metabolites

Electrolytes and metabolites:For iron and copper, some related proteins are also included.

Test	Patient type	Lower limit	Upper limit	Unit	Comments	-			275, 280, 281	295, 296, 297	mOsm/kg	Plasma weight excludes solutes	-			Slightly less than osmolality		mOsm/L	Plasma volume includes solutes	-			3.0^[164]	7.0	mmol/L		-	7	18, 21	mg/dL	-			0.18	0.48	mmol/L		-	Female	2.0	7.0	mg/dL		-	Male	2.1	8.5	mg/dL		-		Male	60, 68^[165]	90, 118	μmol/L		-	0.7, 0.8^[166]	1.0, 1.3	mg/dL	-	Female	50, 68	90, 98	μmol/L	-	0.6, 0.8	1.0, 1.1	mg/dL	-	BUN/Creatinine Ratio		5	35	–		-	Plasma glucose (fasting)		3.8, 4.0	6.0, 6.1	mmol/L	See also glycated hemoglobin (in hematology)	-	65, 70, 72^[167]	100, 110	mg/dL	-	Full blood glucose (fasting)		3.3	5.6	mmol/L	-	60	100	mg/dL	-			3.9^[168]	7.8	mmol/L	-	70^[169]	140	mg/dL	-	Lactate (Venous)		4.5	19.8	mg/dL		-	0.5^[170]	2.2	mmol/L		-	Lactate (Arterial)		4.5	14.4	mg/dL		-	0.5	1.6	mmol/L		-			300	900	μg/dL		-	34^[171]	102	μmol/L		-	Ketones			1	mg/dL		-		0.1	mmol/L

Medication

Test	Lower limit	Upper limit	Unit	Comments
	0.5^[172]	2.0	ng/mL	Narrow therapeutic window
	0.6	2.6	nmol/L
	0.4,^[173] 0.5,^[174] ^[175] 0.8^[176]	1.3	mmol/L	Narrow therapeutic window
		30^[177]	mg/L	Risk of paracetamol toxicity at higher levels
		200	μmol/L

See also

• Cardiology diagnostic tests and procedures
• Comprehensive metabolic panel
• Medical technologist
• Reference range

External links

• Descriptions at amarillomed.com
• Values at lymphomation.org

Further reading

• Rappoport . n. . Paik . P. . Oskotsky . B. . Tor . R. . Ziv . E. . Zaitlen . N. . Butte . A. . 4 November 2017 . Creating ethnicity-specific reference intervals for lab tests from EHR data . 10.1101/213892 .

Notes and References

1. Web site: Reference Ranges and What They Mean. Lab Tests Online (USA). 22 June 2013. 28 August 2013. https://web.archive.org/web/20130828020717/http://labtestsonline.org/understanding/features/ref-ranges/start/6. dead.
2. https://books.google.com/books?id=Je_pJfb2r0cC&pg=PA19 Page 19
3. Bransky A, Larsson A, Aardal E, Ben-Yosef Y, Christenson RH. A Novel Approach to Hematology Testing at the Point of Care. . J Appl Lab Med . 2021 . 6 . 2 . 532–542 . 33274357 . 10.1093/jalm/jfaa186 . 7798949 .
4. https://books.google.com/books?id=BfdighlyGiwC "Units of measurement"
5. http://findarticles.com/p/articles/mi_m3230/is_4_32/ai_61893437/ "Arterial versus venous reference ranges"
6. 10.1097/AOG.0b013e3181c2bde8. 19935037. Pregnancy and Laboratory Studies. Obstetrics & Gynecology. 114. 6. 1326–31. 2009. Abbassi-Ghanavati . M. . Greer . L. G. . Cunningham . F. G. . 24249021.
7. Armbruster. David. Miller . The Joint Committee for Traceability in Laboratory Medicine (JCTLM): A Global Approach to Promote the Standardisation of Clinical Laboratory Test Results. The Clinical Biochemist Reviews. August 2007. 28. 3. 105–14. 1994110. 17909615.
8. Sample Sizes for Prediction Intervals. William Q. Meeker & Gerald J. Hahn. 10.1080/00224065.1982.11978821. Journal of Quality Technology. 14. 1982. 4. 201–206 .
9. https://www.uniprot.org/uniprot/P01189 PROOPIOMELANOCORTIN; NCBI / POMC
10. Derived from molar values using molar mass of 22.99 g•mol−1
11. Derived from molar values using molar mass of 39.10 g•mol−1
12. Derived from molar values using molar mass of 35.45 g•mol−1
13. Larsson L, Ohman S . Serum ionized calcium and corrected total calcium in borderline hyperparathyroidism . Clin. Chem. . 24 . 11 . 1962–65 . November 1978 . 709830 . 10.1093/clinchem/24.11.1962. free .
14. Derived from molar values using molar mass of 40.08  g•mol−1
15. Derived from mass values using molar mass of 40.08  g•mol−1
16. Web site: Slon S . Serum Iron . 2006-09-22 . University of Illinois Medical Center . 2006-07-06 . dead . https://web.archive.org/web/20061028111833/http://uimc.discoveryhospital.com/main.php?t=enc&id=1456 . 2006-10-28 .
17. http://www.dclmexico.com/ingles/hierro_sl.pdf Diagnostic Chemicals Limited > Serum Iron-SL Assay
18. Derived from mass values using molar mass of 55.85 g•mol−1
19. http://www.clinchem.org/cgi/reprint/45/1/131.pdf Table 1.
20. Derived by dividing mass values with molar mass
21. https://www.nlm.nih.gov/medlineplus/ency/article/003490.htm Ferritin
22. Web site: Hemochromatosis Workup. Andrea Duchini. Medscape. 2016-07-14. Updated: Jan 02, 2016
23. Derived from mass values using molar mass of 450,000 g•mol−1
24. Mitchell ML, Filippone MD, Wozniak TF . Metastatic carcinomatous cirrhosis and hepatic hemosiderosis in a patient heterozygous for the H63D genotype . Arch. Pathol. Lab. Med. . 125 . 8 . 1084–87 . August 2001 . 11473464 . 10.5858/2001-125-1084-MCCAHH.
25. Diaz J, Tornel PL, Martinez P . Reference intervals for blood ammonia in healthy subjects, determined by microdiffusion . Clin. Chem. . 41 . 7 . 1048 . July 1995 . 7600690 . 10.1093/clinchem/41.7.1048a. free .
26. Derived from molar values using molar mass of 17.03 g/mol
27. Derived from mass values using molar mass of 63.55 g•mol−1
28. Derived from mass using molar mass of 151kDa
29. Book: Walter F. Boron . Medical Physiology: A Cellular And Molecular Approaoch . Elsevier/Saunders . 2005. 978-1-4160-2328-9. 849.
30. Web site: Archived copy . 2010-01-17 . dead . https://web.archive.org/web/20100307231954/http://www.dlolab.com/PDFs/DLO-OCTOBER-2008-LAB-UPDATE.pdf . 2010-03-07 .
31. Derived from molar values using molar mass of 65.38 g/mol
32. Derived from mass values using molar mass of 65.38 g/mol
33. Derived from molar values using molar mass of 24.31 g/mol
34. Derived from mass values using molar mass of 24.31 g/mol
35. Middleton P, Kelly AM, Brown J, Robertson M . Agreements between arterial and central venous values for pH, bicarbonate, base excess, and lactate . Emerg Med J . 23 . 8 . 622–24 . August 2006 . 16858095 . 2564165 . 10.1136/emj.2006.035915 .
36. http://www.brooksidepress.org/Products/OperationalMedicine/DATA/operationalmed/Lab/ABG_ArterialBloodGas.htm The Medical Education Division of the Brookside Associates / ABG (Arterial Blood Gas)
37. Derived from molar values using molar mass of 1.01 g•mol−1
38. http://www.merck.com/mmhe/appendixes/ap2/ap2b.html Merck Manuals > Common Medical Tests > Blood Tests
39. Derived from mmHg values using 0.133322 kPa/mmHg
40. Derived from molar values using molar mass of 44.010 g/mol
41. http://www.bloodbook.com/ranges.html Blood Test Results – Normal Ranges
42. Derived from molar values using molar mass of 61 g/mol
43. Derived from mass using molecular weight of 65kD
44. Derived from mass values using molar mass of 585g/mol
45. Derived from molar values using molar mass of 585g/mol
46. Last page of Book: Deepak A. Rao . Le, Tao . Bhushan, Vikas . First Aid for the USMLE Step 1 2008 (First Aid for the Usmle Step 1) . McGraw-Hill Medical . 2007 . 978-0-07-149868-5 . registration .
47. http://www.gpnotebook.co.uk/simplepage.cfm?ID=322240579 GPnotebook > reference range (AST)
48. Fachwörterbuch Kompakt Medizin E-D/D-E. Author: Fritz-Jürgen Nöhring. Edition 2. Publisher:Elsevier, Urban&FischerVerlag, 2004. . Length: 1288 pages
49. Web site: Gamma-GT . Leistungsverzeichnis . Medizinisch-Diagnostische Institute . 20 November 2011 . dead . https://web.archive.org/web/20120425233448/http://www.mdi-labor.de/l_leistungsverzeichnis_detail.php?u_id=663&init=letter . 25 April 2012 .
50. https://books.google.com/books?id=AUSIRcV_as0C&pg=PA585 Page 585
51. http://www.medialabinc.net/muscle-keyword.aspx Muscle Information and Courses from MediaLab, Inc. > Cardiac Biomarkers
52. Web site: Ashvarya Mangla. Troponins. 2017-07-24. medscape. Updated: Jan 14, 2015
53. 2016-07-01. Plasma cardiac troponin I concentrations in healthy neonates, children and adolescents measured with a high sensitive immunoassay method: High sensitive troponin I in pediatric age. Clinica Chimica Acta. en. 458. 68–71. 10.1016/j.cca.2016.04.029. 27118089. 0009-8981. Caselli. C.. Cangemi. G.. Masotti. S.. Ragusa. R.. Gennai. I.. Del Ry. S.. Prontera. C.. Clerico. A..
54. Baum. Hannsjörg. Hinze. Anika. Bartels. Peter. Neumeier. Dieter. 2004-12-01. Reference values for cardiac troponins T and I in healthy neonates. Clinical Biochemistry. en. 37. 12. 1079–82. 10.1016/j.clinbiochem.2004.08.003. 15589813. 0009-9120.
55. Brenden CK, Hollander JE, Guss D, etal . Gray zone BNP levels in heart failure patients in the emergency department: results from the Rapid Emergency Department Heart Failure Outpatient Trial (REDHOT) multicenter study . American Heart Journal . 151 . 5 . 1006–11 . May 2006 . 16644322 . 10.1016/j.ahj.2005.10.017.
56. Strunk A, Bhalla V, Clopton P, etal . Impact of the history of congestive heart failure on the utility of B-type natriuretic peptide in the emergency diagnosis of heart failure: results from the Breathing Not Properly Multinational Study . The American Journal of Medicine . 119 . 1 . 69.e1–11 . January 2006 . 16431187 . 10.1016/j.amjmed.2005.04.029. free .
57. https://books.google.com/books?id=AUSIRcV_as0C&pg=PA220 Page 220
58. Derived from values in mg/dL to mmol/L, by dividing by 89, according to faqs.org: What are mg/dL and mmol/L? How to convert? Glucose? Cholesterol? Last Update July 21, 2009. Retrieved on July 21, 2009
59. Derived from values in mg/dL to mmol/L, using molar mass of 386.65 g/mol
60. http://www.rcpamanual.edu.au/sections/pathologytest.asp?s=33&i=450 Royal College of Pathologists of Australasia; Cholesterol (HDL and LDL) – plasma or serum
61. http://www.americanheart.org/presenter.jhtml?identifier=183 What Your Cholesterol Levels Mean.
62. Derived from values in mmol/L, using molar mass of 386.65 g/mol
63. Web site: HDL Cholesterol: The Test. September 3, 2001. https://web.archive.org/web/20010903133121/http://www.labtestsonline.org/understanding/analytes/hdl/test.html. 2001-09-03.
64. http://www.gpnotebook.co.uk/simplepage.cfm?ID=-100270014 GP Notebook > range (reference, ca-125)
65. http://www.clinlabnavigator.com/Test-Interpretations/ca-125.html ClinLab Navigator > Test Interpretations > CA-125
66. Bjerner J, Høgetveit A, Wold Akselberg K, etal . 12545738 . Reference intervals for carcinoembryonic antigen (CEA), CA125, MUC1, Alfa-foeto-protein (AFP), neuron-specific enolase (NSE) and CA19.9 from the NORIP study . Scandinavian Journal of Clinical and Laboratory Investigation . 68. 8. 703–13 . June 2008 . 18609108 . 10.1080/00365510802126836 .
67. http://www.medicinenet.com/carcinoembryonic_antigen/article.htm Carcinoembryonic Antigen(CEA)
68. Luboldt. Hans-Joachim. Schindler. Joachim F.. Rübben. Herbert. Age-Specific Reference Ranges for Prostate-Specific Antigen as a Marker for Prostate Cancer. EAU-EBU Update Series. 5. 1. 2007. 38–48. 1871-2592. 10.1016/j.eeus.2006.10.003.
69. Basuyau JP, Mallet E, Leroy M, Brunelle P . Reference intervals for serum calcitonin in men, women, and children . Clinical Chemistry . 50 . 10 . 1828–30 . October 2004 . 15388660 . 10.1373/clinchem.2003.026963. free .
70. http://thyroid.about.com/od/gettestedanddiagnosed/a/tshtestwars.htm The TSH Reference Range Wars: What's "Normal?", Who is Wrong, Who is Right...
71. http://www.aace.com/newsroom/press/2006/index.php?r=20060110 2006 Press releases: Thyroid Imbalance? Target Your Numbers
72. http://thyroid.about.com/od/gettestedanddiagnosed/a/tshtestwars.htm The TSH Reference Range Wars: What's "Normal?", Who is Wrong, Who is Right...
73. Web site: Demers. Laurence M.. Carole A. Spencer. LMPG: Laboratory Support for the Diagnosis and Monitoring of Thyroid Disease. National Academy of Clinical Biochemistry (USA). 2002. 2007-04-13. 2008-11-20. https://web.archive.org/web/20081120130504/http://www.nacb.org/lmpg/thyroid_LMPG_PDF.stm. dead. – see Section 2. Pre-analytic factors
74. http://labs.unchealthcare.org/labstestinfo/f_tests/free_t4.htm Free T4; Thyroxine, Free; T4, Free
75. Derived from molar values using molar mass of 776.87 g/mol
76. van der Watt G, Haarburger D, Berman P . Euthyroid patient with elevated serum free thyroxine . Clinical Chemistry . 54 . 7 . 1239–41 . July 2008 . 18593963 . 10.1373/clinchem.2007.101428. free .
77. Derived from mass values using molar mass of 776.87 g/mol
78. Derived from mass values using molar mass of 650.98 g/mol
79. . Cioffi M, Gazzerro P, Vietri MT, etal . Serum concentration of free T3, free T4 and TSH in healthy children . Journal of Pediatric Endocrinology & Metabolism . 14 . 9 . 1635–39 . 2001 . 11795654 . 10.1515/jpem.2001.14.9.1635. 34910563 .
80. http://www.thyroidmanager.org/chapter6/Ch-6b-2.htm Table 4: Typical reference ranges for serum assays
81. Web site: Andrology Australia: Your Health > Low Testosterone > Diagnosis. 2008-11-28. 2012-02-17. https://web.archive.org/web/20120217051046/http://www.andrologyaustralia.org/pageContent.asp?pageCode=LOWTESTDIAG#LOWTESTDIAGNORM. dead.
82. Derived from mass values using molar mass of 288.42g/mol
83. Derived from molar values using molar mass of 288.42g/mol
84. https://www.nlm.nih.gov/medlineplus/ency/article/003707.htm#Normal%20Values MedlinePlus > Testosterone
85. Derived from mass values using molar mass of 330.46g/mol
86. http://www.gpnotebook.co.uk/simplepage.cfm?ID=436600899 reference range (FSH)
87. Values taken from day 1 after LH surge in: Stricker R, Eberhart R, Chevailler MC, Quinn FA, Bischof P, Stricker R . 524952 . Establishment of detailed reference values for luteinizing hormone, follicle stimulating hormone, estradiol, and progesterone during different phases of the menstrual cycle on the Abbott ARCHITECT analyzer . Clinical Chemistry and Laboratory Medicine . 44 . 7 . 883–87 . 2006 . 16776638 . 10.1515/CCLM.2006.160.
88. http://www.nyhq.org/Reference_Ranges& New York Hospital Queens > Services and Facilities > Patient Testing > Pathology > New York Hospital Queens Diagnostic Laboratories > Test Directory > Reference Ranges
89. http://www.mayomedicallaboratories.com/test-catalog/Clinical+and+Interpretive/8663 Mayo Medical Laboratories > Test ID: LH, Luteinizing Hormone (LH), Serum
90. http://www.gpnotebook.co.uk/simplepage.cfm?ID=570818627&linkID=24801&cook=yes GPNotebook – reference range (oestradiol)
91. Derived from molar values using molar mass of 272.38g/mol
92. Total amount multiplied by 0.022 according to 2.2% presented in: Wu CH, Motohashi T, Abdel-Rahman HA, Flickinger GL, Mikhail G . Free and protein-bound plasma estradiol-17 beta during the menstrual cycle . J. Clin. Endocrinol. Metab. . 43 . 2 . 436–45 . August 1976 . 950372 . 10.1210/jcem-43-2-436.
93. Derived from mass values using molar mass of 314.46 g/mol
94. Bhattacharya Sudhindra Mohan (July/August 2005) Mid-luteal phase plasma progesterone levels in spontaneous and clomiphene citrate induced conception cycles J Obstet Gynecol India Vol. 55, No. 4 : July/August 2005 pp. 350–52
95. http://www.mayomedicallaboratories.com/test-catalog/Clinical+and+Interpretive/8493 Dehydroepiandrosterone Sulfate (DHEA-S), Serum
96. http://www.mayomedicallaboratories.com/test-catalog/print.php?unit_code=91215 Unit Code 91215
97. http://www.mayomedicallaboratories.com/test-catalog/print/89711 Antimullerian Hormone (AMH), Serum
98. Derived from mass values using 140,000 g/mol, as given in:
    • Hampl R, Šnajderová M, Mardešić T . Antimüllerian hormone (AMH) not only a marker for prediction of ovarian reserve . Physiological Research . 60 . 2 . 217–23 . 2011 . 21114374 . 10.33549/physiolres.932076 . free .
99. Web site: Nieman . Lynnette K . Measurement of ACTH, CRH, and other hypothalamic and pituitary peptides . www.uptodate.com . UpToDate . 25 June 2021 . 29 September 2019.
100. http://www.goodhope.org.uk/departments/pathweb/refranges.htm Biochemistry Reference Ranges at Good Hope Hospital
101. Derived from molar values using molar mass of 362 g/mol
102. Friedrich N, Alte D, Völzke H, etal . Reference ranges of serum IGF-1 and IGFBP-3 levels in a general adult population: results of the Study of Health in Pomerania (SHIP) . Growth Hormone & IGF Research . 18 . 3 . 228–37 . June 2008 . 17997337 . 10.1016/j.ghir.2007.09.005.
103. Taken from the assay method giving the lowest and highest estimate, respectively, from Table 2 in: Beltran L, Fahie-Wilson MN, McKenna TJ, Kavanagh L, Smith TP . Serum total prolactin and monomeric prolactin reference intervals determined by precipitation with polyethylene glycol: evaluation and validation on common immunoassay platforms . Clinical Chemistry . 54 . 10 . 1673–81 . October 2008 . 18719199 . 10.1373/clinchem.2008.105312. free .
104. Derived from molar values using molar mass of 9.4 kDa
105. https://www.ncbi.nlm.nih.gov/pmc/articles/mid/NIHMS10653/table/T2/ Table 2
106. Derived from mass values using molar mass of 9.4 kDa
107. Derived from molar values using molar mass 400.6 g/mol
108. Book: Bender, David A. . Vitamin D . Nutritional biochemistry of the vitamins . Cambridge University Press . Cambridge . 2003 . 978-0-521-80388-5 . https://books.google.com/books?id=pxEJNs0IUo4C. Retrieved December 10, 2008 through Google Book Search.
109. Bischoff-Ferrari HA, Dietrich T, Orav EJ, etal . Higher 25-hydroxyvitamin D concentrations are associated with better lower-extremity function in both active and inactive persons aged > or 60 y . The American Journal of Clinical Nutrition . 80 . 3 . 752–58 . September 2004 . 15321818 . 10.1093/ajcn/80.3.752. free .
110. Reusch J, Ackermann H, Badenhoop K . Cyclic changes of vitamin D and PTH are primarily regulated by solar radiation: 5-year analysis of a German (50 degrees N) population . Horm. Metab. Res. . 41 . 5 . 402–07 . May 2009 . 19241329 . 10.1055/s-0028-1128131 . 260166796 .
111. Vasquez A, Cannell J . Calcium and vitamin D in preventing fractures: data are not sufficient to show inefficacy . BMJ . 331 . 7508 . 108–09; author reply 109 . July 2005 . 16002891 . 558659 . 10.1136/bmj.331.7508.108-b.
112. http://www.adeeva.com/resources/bloodtestscomplete.html Adëeva Nutritionals Canada > Optimal blood test values
113. Converted from values in mcU/mL by dividing with a factor of 11.2 mcU/mL per ng/(mL*hour), as given in:
     • New Assays for Aldosterone, Renin and Parathyroid Hormone University of

     Washington, Department of Laboratory Medicine. Retrieved Mars 2011

114. Pratt RE, Flynn JA, Hobart PM, Paul M, Dzau VJ . Different secretory pathways of renin from mouse cells transfected with the human renin gene . The Journal of Biological Chemistry . 263 . 7 . 3137–41 . March 1988 . 10.1016/S0021-9258(18)69046-5 . 2893797 . free .
115. http://depts.washington.edu/labweb/referencelab/print/endo.pdf New Assays for Aldosterone, Renin and Parathyroid Hormone
116. Converted from values in ng/(mL*hour) by multiplying with a factor of 11.2 mcU/mL per ng/(mL*hour), as given in:
     • New Assays for Aldosterone, Renin and Parathyroid Hormone University of

     Washington, Department of Laboratory Medicine. Retrieved Mars 2011

117. Converted from mass values using molar mass of 360.44 g/mol
118. Tiu SC, Choi CH, Shek CC, etal . The use of aldosterone-renin ratio as a diagnostic test for primary hyperaldosteronism and its test characteristics under different conditions of blood sampling . The Journal of Clinical Endocrinology and Metabolism . 90 . 1 . 72–78 . January 2005 . 15483077 . 10.1210/jc.2004-1149. 10.1.1.117.5182 .
119. http://www.cmft.nhs.uk/directorates/labmedicine/USERGUIDE/pdfs/Haem%20-%20Coagulation%20Ref%20Ranges.pdf Central Manchester University Hospitals / Reference ranges
120. http://www.hosp.uky.edu/Clinlab/report.pdf University of Kentucky Chandler Medical Center > Clinical Lab Reference Range Guide
121. Derived from mass values using molar mass of 441 mol−1
122. http://www.gpnotebook.co.uk/simplepage.cfm?ID=-2087059389&linkID=35554&cook=no GPnotebook > B12
123. Derived form molar values using molar mass of 1355g/mol
124. Derived from mass values using molar mass of 1355g/mol
125. Web site: Homocysteine. www.thedoctorsdoctor.com.
126. Derived from molar values using molar massof 135 g/mol
127. Derived from mass values using molar mass of 176 grams per mol
128. For Driving under the influence by country, see Drunk driving law by country
129. Derived from mass values using molar mass of 46g/mol
130. Derived from mass values using 64,500 g/mol. This molar mass was taken from: Van Beekvelt MC, Colier WN, Wevers RA, Van Engelen BG . 15468862 . Performance of near-infrared spectroscopy in measuring local O2 consumption and blood flow in skeletal muscle . J Appl Physiol . 90 . 2 . 511–19 . 2001 . 11160049. 10.1152/jappl.2001.90.2.511 .
131. http://musom.marshall.edu/usmle/usmlelabvalues.htm Normal Lab Values
132. Reference range list from Uppsala University Hospital ("Laborationslista"). Artnr 40284 Sj74a. Issued on April 22, 2008
133. molar concentration as given for hemoglobin above, but multiplied by 4, according to: Lodemann P, Schorer G, Frey BM . 3091357 . Wrong molar hemoglobin reference values-a longstanding error that should be corrected . Annals of Hematology . 89 . 2 . 209 . February 2010 . 19609525 . 10.1007/s00277-009-0791-x. free .
134. Derived from mass concentration, using molar mass of 64,458 g/mol. This molar mass was taken from: Van Beekvelt MC, Colier WN, Wevers RA, Van Engelen BG . 15468862 . Performance of near-infrared spectroscopy in measuring local O2 consumption and blood flow in skeletal muscle . J Appl Physiol . 90 . 2 . 511–19 . 2001 . 11160049. 10.1152/jappl.2001.90.2.511 . . Subsequently, 1 g/dL = 0.1551 mmol/L
135. Morkis IV, Farias MG, Scotti L. Determination of reference ranges for immature platelet and reticulocyte fractions and reticulocyte hemoglobin equivalent. . Rev Bras Hematol Hemoter . 2016 . 38 . 4 . 310–313 . 27863758 . 10.1016/j.bjhh.2016.07.001 . 5119661 .
136. Brugnara C, Schiller B, Moran J. Reticulocyte hemoglobin equivalent (Ret He) and assessment of iron-deficient states. . Clinical and Laboratory Haematology . 2006 . 28 . 5 . 303–8 . 16999719 . 10.1111/j.1365-2257.2006.00812.x . 1618805 .
137. http://www.lymphomation.org/CBC-blood-counts.htm lymphomation.org > Tests & Imaging > Labs > Complete Blood Count
138. Book: McClatchey, Kenneth D.. Clinical Laboratory Medicine. November 28, 2002. Lippincott Williams & Wilkins. 9780683307511. Google Books.
139. http://www.termedia.pl/magazine.php?magazine_id=10&article_id=6801&magazine_subpage=ABSTRACT "Determination of monocyte count by hematological analyzers, manual method and flow cytometry in Polish population"
140. http://www.gpnotebook.co.uk/simplepage.cfm?ID=-637140985 gpnotebook.co.uk > blood constituents (reference range)
141. http://pathcuric1.swmed.edu/PathDemo/nrrt.htm Normal Reference Range Table
142. Demirin H, Ozhan H, Ucgun T, Celer A, Bulur S, Cil H, Gunes C, Yildirim HA . Normal range of mean platelet volume in healthy subjects: Insight from a large epidemiologic study . Thromb. Res. . 128 . 4 . 358–60 . 2011 . 21620440 . 10.1016/j.thromres.2011.05.007 .
143. http://www.labcareplus.org/docs/REFERENCE_RANGES.pdf Normal Values: RBC, Hgb, Hct, Indices, RDW, Platelets, and MPV (Conventional Units)
144. Lozano M, Narváez J, Faúndez A, Mazzara R, Cid J, Jou JM, Marín JL, Ordinas A . [Platelet count and mean platelet volume in the Spanish population] . es. Med Clin (Barc) . 110 . 20 . 774–77 . 1998 . 9666418 .
145. http://mghlabtest.partners.org/coagbook/co000300.htm Antithrombin CO000300
146. Web site: Home . pathology.bsuh.nhs.uk . November 20, 2009.
147. Böttiger LE, Svedberg CA . Normal erythrocyte sedimentation rate and age . Br Med J . 2 . 5544 . 85–87 . 1967 . 6020854 . 10.1136/bmj.2.5544.85. 1841240.
148. Miller A, Green M, Robinson D . Simple rule for calculating normal erythrocyte sedimentation rate . British Medical Journal . 286 . 6361 . 266 . January 1983 . 6402065 . 1546487 . 10.1136/bmj.286.6361.266.
149. http://iadr.confex.com/iadr/2008Toronto/techprogram/abstract_106289.htm 2730 Serum C-Reactive Protein values in Diabetics with Periodontal Disease
150. Sipahi T, Kara C, Tavil B, Inci A, Oksal A . Alpha-1 antitrypsin deficiency: an overlooked cause of late hemorrhagic disease of the newborn . Journal of Pediatric Hematology/Oncology . 25 . 3 . 274–75 . March 2003 . 12621252 . 10.1097/00043426-200303000-00019.
151. Derived from mass values using molar mass of 44324.5 g/mol
152. Derived from molar values using molar mass of 44324.5 g/mol
153. Web site: Procalcitonin, Serum . . 2015-03-01.
154. http://www.ascls.org/labtesting/labchem.asp The Society for American Clinical Laboratory Science > Chemistry Tests > Immunoglobulins
155. Web site: SSA – Clinical: SS-A/Ro Antibodies, IgG, Serum . www.mayocliniclabs.com . Mayo Clinic Laboratories . 2 July 2020.
156. Web site: SSB – Clinical: SS-B/La Antibodies, IgG, Serum . www.mayocliniclabs.com . Mayo Clinic Laboratories . 2 July 2020.
157. Web site: ADNA – Clinical: DNA Double-Stranded Antibodies, IgG, Serum . www.mayocliniclabs.com . Mayo Clinic Laboratories . 2 July 2020.
158. http://www.chronolab.com/rheumatic/range.htm chronolab.com > Autoantibodies associated with rheumatic diseases > Reference ranges
159. Web site: AMA – Clinical: Mitochondrial Antibodies (M2), Serum . www.mayocliniclabs.com . Mayo Clinic Laboratories . 2 July 2020.
160. Rajkumar SV, Kyle RA, Therneau TM . Serum free light chain ratio is an independent risk factor for progression in monoclonal gammopathy of undetermined significance . Blood . 106 . 3 . 812–17 . August 2005 . 15855274 . 1895159 . 10.1182/blood-2005-03-1038 . etal .
161. Derived from mass using molar mass of 25,106 g/mol
162. Ageno W, Finazzi S, Steidl L, etal . Plasma measurement of D-dimer levels for the early diagnosis of ischemic stroke subtypes . Archives of Internal Medicine . 162 . 22 . 2589–93 . 2002 . 12456231 . 10.1001/archinte.162.22.2589. 2434/51239 . free .
163. Kline JA, Williams GW, Hernandez-Nino J . D-dimer concentrations in normal pregnancy: new diagnostic thresholds are needed . Clinical Chemistry . 51 . 5 . 825–29 . May 2005 . 15764641 . 10.1373/clinchem.2004.044883. free .
164. Gardner MD, Scott R . Age- and sex-related reference ranges for eight plasma constituents derived from randomly selected adults in a Scottish new town . Journal of Clinical Pathology . 33 . 4 . 380–85 . April 1980 . 7400337 . 1146084 . 10.1136/jcp.33.4.380.
165. Finney H, Newman DJ, Price CP . 35866310 . Adult reference ranges for serum cystatin C, creatinine and predicted creatinine clearance . Annals of Clinical Biochemistry . 37 . 1 . 49–59 . January 2000 . 10672373 . 10.1258/0004563001901524. free .
166. Derived from molar values by multiplying with the molar mass of 113.118 g/mol, and divided by 10.000 to adapt from μg/L to mg/dL
167. Derived from molar values using molar mass of 180g/mol
168. Derived from mass values using molar mass of 180g/mol
169. Web site: Diabetes – Prevention. Cleveland Clinic. 2016-06-23. Last revised 1/15/2013
170. Derived from mass values using molar mass of 90.08 g/mol
171. Derived from mass values using molar mass of 88.06 g/mol
172. https://books.google.com/books?id=BfdighlyGiwC&pg=PA700 Page 700
173. The UK Electronic Medical Compendium recommends 0.4–0.8 mmol/L plasma lithium level in adults for prophylaxis of recurrent affective bipolar manic-depressive illness Camcolit 250 mg Lithium Carbonate Revision 2 December 2010, Retrieved 5 May 2011
174. Amdisen A. . Clinical and serum level monitoring in lithium therapy and lithium intoxication. J. Anal. Toxicol. . 2. 5. 193–202. 1978. 10.1093/jat/2.5.193.
175. R. Baselt, Disposition of Toxic Drugs and Chemicals in Man, 8th edition, Biomedical Publications, Foster City, CA, 2008, pp. 851–54.
176. One study (Solomon . D.. Ristow . W.. Keller . M.. Kane . J.. Gelenberg . A.. Rosenbaum . J.. Warshaw . M.. Serum lithium levels and psychosocial function in patients with bipolar I disorder. The American Journal of Psychiatry. 153. 10. 1301–07. 1996. 8831438 . 10.1176/ajp.153.10.1301.) concluded a "low" dose of 0.4–0.6 mmol/L serum lithium treatment for patients with bipolar 1 disorder had less side effects, but a higher rate of relapse, than a "standard" dose of 0.8–1.0 mmol/L. However, a reanalysis of the same experimental data (Perlis . R.. Sachs . G.. Lafer . B.. Otto . M.. Faraone . S.. Kane . J.. Rosenbaum . J.. 12103424. Effect of abrupt change from standard to low serum levels of lithium: A reanalysis of double-blind lithium maintenance data. The American Journal of Psychiatry. 159. 7. 1155–59. 2002. 12091193 . 10.1176/appi.ajp.159.7.1155.) concluded the higher rate of relapse for the "low" dose was due to abrupt changes in the lithium serum levels
177. Book: Rosen's Emergency Medicine – Concepts and Clinical Practice. John Marx . Ron Walls . Robert Hockberger . Elsevier Health Sciences. 2013. 9781455749874.