| Hölzel WGE, 1987, Clin Chem, 33, 57-61 | 2.0 | | Males | Healthy (excl pregnant) | Serum |
| Pineda-Tenor D , Laserna-Mendieta EJ, Timon-Zapata J, Rodelgo-Jimenez L, Ramos-Corral R, Recio-Montealegre A and Gomez-Serranillos Reus M, 2013, Clin Chem Lab Med, 51, 851-62 | 3.4 | 5.9 | Males | Healthy (excl pregnant) | Serum |
| Pineda-Tenor D , Laserna-Mendieta EJ, Timon-Zapata J, Rodelgo-Jimenez L, Ramos-Corral R, Recio-Montealegre A and Gomez-Serranillos Reus M, 2013, Clin Chem Lab Med, 51, 851-62 | 3.0 | 5.1 | Females | Healthy (excl pregnant) | Serum |
| González-Revaldería J., García-Bermejo S., Menchén-Herreros A., and Fernández-Rodriguez E, 1991, Clin Chem, 37, 596 | 2.68 | 3.44 | Mixed | Healthy (excl pregnant) | Serum |
| Gowans EMS, Fraser G., 1987, Clin Chem, 33, 717 | 2.2 | 4.1 | Mixed | Healthy (excl pregnant) | Serum |
| Harris EK, Kanofsky P, Shakarji G and Cotlove E, 1970, Clin Chem, 16, 1022-7 | 3.9 | 6.3 | Mixed | Healthy (excl pregnant) | Serum |
| Eckfeldt J,Chambless Ll and Shen Y, 1994, Arch Pathol Lab Med, 118, 496-500 | 2.8 | 5.8 | Mixed | Healthy (excl pregnant) | Serum |
| Hölzel WGE, 1987, Clin Chem, 33, 57-61 | 2.7 | | Females | Healthy (excl pregnant) | Serum |
| Clark GH, Fraser CG. , 1993, Ann Clin Biochem, 30, 373-76 | 2.5 | 3.7 | Mixed | Healthy (excl pregnant) | Serum |
| Young DS, Harris EK and Cotlove E, 1971, Clin Chem, 17, 403-10 | 2.96 | 2.18 | Males | Healthy (excl pregnant) | Serum |
| Carobene A, Aarsand AK, Guerra E et al, 2019, Clin Chem, 65 (8), 1031-41 | 2.5 | 5.1 | Mixed | Healthy (excl pregnant) | Serum |
| Costongs GMPJ, Janson PCW and Bas BM, 1985, J Clin Chem Clin Biochem, 23, 7-16 | 3.2 | | Mixed | Healthy (excl pregnant) | Serum |
| Bailey D, Bevilacqua V, Colantonio DA, Pasic MD, Perumal N, Chan MK and Adeli K, 2014, Clin Chem, 60, 518-29 | | | Mixed | Healthy (excl pregnant) | Plasma |
| Dimitri G, Bolner A and Gheller A, 1992, Biochim Clin, 16, 401-3 | 4.45 | | Mixed | Healthy (excl pregnant) | Serum |
| Pineda-Tenor D , Laserna-Mendieta EJ, Timon-Zapata J, Rodelgo-Jimenez L, Ramos-Corral R, Recio-Montealegre A and Gomez-Serranillos Reus M, 2013, Clin Chem Lab Med, 51, 851-62 | 4.5 | 5.6 | Females | Healthy (excl pregnant) | Serum |
| Bailey D, Bevilacqua V, Colantonio DA, Pasic MD, Perumal N, Chan MK and Adeli K, 2014, Clin Chem, 60, 518-29 | | | Mixed | Healthy (excl pregnant) | Plasma |
| Bailey D, Bevilacqua V, Colantonio DA, Pasic MD, Perumal N, Chan MK and Adeli K, 2014, Clin Chem, 60, 518-29 | 2.3 | 4.7 | Mixed | Healthy (excl pregnant) | Plasma |
| Fraser CG and Hearne CR, 1982, Ann Clin Biochem, 19, 431-4 | 6.7 | 5.5 | Males | Healthy (excl pregnant) | Plasma |
| Fraser CG and Williams P, 1983, Clin Chem, 29, 508-10 | 4.4 | 9.7 | Males | Non-healthy (excl pregnant) | Plasma |
| Fraser CG., Cummings ST., Wilkinson SP., Neville RG., Knox JDE, Ho O and MacWalter RS, 1989, Clin Chem, 35, 783-6 | 2.6 | 3.4 | Mixed | Healthy (excl pregnant) | Serum |
| Statland BE, Winkel P and Bokelund H, 1973, Clin Chem, 19, 1374-9 | 3.8 | 9.5 | Males | Healthy (excl pregnant) | Serum |
| Qi Z, Chen Y, Zhang L, Ma X, Wang F, Cheng Q, Du J, Hao Y, Chi S, Cui W, 2016, Clin Chim Acta, 452, 87-91 | 2.5 | 5.08 | Mixed | Healthy (excl pregnant) | Plasma |
| Chitto G, Fabi A, Franzini C, Galletta G, Leonardi A, Marelli M and Morelli AM, 1994, Biochim Clin, 18, 673-690 | 3.2 | | Mixed | Healthy (excl pregnant) | Serum |
| Pickup JF, Harris EK, Kearns M and Brown SS, 1977, Clin Chem, 23, 842-50 | 3.2 | | Males | Healthy (excl pregnant) | Serum |
| Winkel P, Statland BE and Bokelund H, 1974, Clin Chem, 20, 1520-7 | 2.8 | 0.5 | Males | Healthy (excl pregnant) | Serum |
| Petersen PH, Feldt-Rasmussen U, Horder M, Blaabjerg O, Thygesen K, 1981, Scand J Clin Lab Invest, 41, 143-50 | 3.8 | | Males | Healthy (excl pregnant) | Serum |
| Petersen PH, Feldt-Rasmussen U, Horder M, Blaabjerg O, Thygesen K, 1981, Scand J Clin Lab Invest, 41, 143-50 | 1.5 | | Males | Healthy (excl pregnant) | Serum |
| Juan-Pereira L., and Fuentes-Arderiu X., 1989, Clin Chem, 35, 1544 | 4.1 | 5.1 | Mixed | Healthy (excl pregnant) | Serum |
| Petersen PH, Feldt-Rasmussen U, Horder M, Blaabjerg O, Thygesen K, 1981, Scand J Clin Lab Invest, 41, 143-50 | 3.4 | | Females | Healthy (excl pregnant) | Serum |
| Morris HA, Wishart JM, Horowitz M, Need AG and Nordin BEC, 1990, Ann Clin Biochem, 27, 562-8 | 3.2 | 6.0 | Females | Healthy (excl pregnant) | Serum |
| Carobene A, Graziani MS, Lo Cascio C, Tretti L, Cremonese E, Yabarek T, Gambaro G and Ceriotti F., 2012, Clin Chem Lab Med, 50, 841-4 | 1.5 | | Mixed | Healthy (excl pregnant) | Plasma |
| Gallagher SK, Johnson AK, Milne DB, 1992, Clin Chem, 38, 1449-53 | 11.0 | | Females | Healthy (excl pregnant) | Serum |
| Hölzel WGE, 1987, Clin Chem, 33, 1133-6 | 2.7 | | Females | Healthy (excl pregnant) | Serum |
| Hölzel WGE, 1987, Clin Chem, 33, 1133-6 | 2.1 | | Males | Healthy (excl pregnant) | Serum |
| Pineda-Tenor D , Laserna-Mendieta EJ, Timon-Zapata J, Rodelgo-Jimenez L, Ramos-Corral R, Recio-Montealegre A and Gomez-Serranillos Reus M, 2013, Clin Chem Lab Med, 51, 851-62 | 4.3 | 5.3 | Males | Healthy (excl pregnant) | Serum |
| Lacher DA, Hughes JP and Carroll MD, 2010, National Health Statistics Reports , 21, | 3.5 | 7.5 | Mixed | Healthy (excl pregnant) | Serum |
| Lacher DA, Hughes JP and Carroll MD, 2005, Clin Chem, 51, 450-2 | 2.8 | 8.9 | Mixed | Healthy (excl pregnant) | Serum |
| Qi Z, Chen Y, Zhang L, Ma X, Wang F, Cheng Q, Du J, Hao Y, Chi S, Cui W, 2016, Clin Chim Acta, 452, 87-91 | 2.4 | 2.74 | Males | Healthy (excl pregnant) | Plasma |
| Qi Z, Chen Y, Zhang L, Ma X, Wang F, Cheng Q, Du J, Hao Y, Chi S, Cui W, 2016, Clin Chim Acta, 452, 87-91 | 2.76 | 5.02 | Females | Healthy (excl pregnant) | Plasma |
| Carobene A, Graziani MS, Lo Cascio C, Tretti L, Cremonese E, Yabarek T, Gambaro G and Ceriotti F., 2012, Clin Chem Lab Med, 50, 841-4 | 2.1 | | Mixed | Healthy (excl pregnant) | Plasma |
| Carobene A, Graziani MS, Lo Cascio C, Tretti L, Cremonese E, Yabarek T, Gambaro G and Ceriotti F., 2012, Clin Chem Lab Med, 50, 841-4 | 2.5 | | Mixed | Healthy (excl pregnant) | Plasma |
| Bailey D, Bevilacqua V, Colantonio DA, Pasic MD, Perumal N, Chan MK and Adeli K, 2014, Clin Chem, 60, 518-29 | | | Mixed | Healthy (excl pregnant) | Plasma |
