Quantitative human chorionic gonadotropin measurement in urine using the Access immunoassay
Er TK, Tsai LY, Ginés Ruiz MA, et al. Quantitative human chorionic gonadotropin measurement in urine using the Access immunoassay. Am J Emerg Med 2008; 26:103-4.
Three consecutive false negative pregnancy tests in a twin pregnancy: A case report
[serial online], 6. Available at, Accessed February 10, 2010
Yunus D, Muppala H, Hamer F, Clarke F. Three consecutive false negative pregnancy tests in a twin pregnancy: a case report. Int J Gynecol Obstet [serial online] 2007;6. Available at:www.ispub.com/journal/the_internet_journal_of_gynecology_and_obstetrics/volume_6_number_2_6/article/three_consecutive_false_negative_pregnancy_tests_in_a_twin_pregnancy_a_case_report.html. Accessed February 10, 2010.
The "hook effect": High concentrations of prostate-specific antigen giving artifactually low values on one-step immunoassay
Wolf BA, Garrett NC, Nahm MH. The "hook effect": high concentrations of prostate-specific antigen giving artifactually low values on one-step immunoassay. N Engl J Med 1989; 320:1755-6.
Evaluation of home pregnancy test kits for reliability
serial online, Available at, Accessed February 10, 2010
Wheeler MJ. Evaluation of home pregnancy test kits for reliability. Nursing Times [serial online] 2007; 103: 30-1. Available at: www.nursingtimes.net/nursing-practice-clinical-research/evaluation-of-home-pregnancy-test-kits-for-reliability/199782.article. Accessed February 10, 2010.
Malignant potential of gestational trophoblastic disease at the extreme ages of reproductive life
Bandy LC, Clarke-Pearson DL, Hammond CB. Malignant potential of gestational trophoblastic disease at the extreme ages of reproductive life. Obstet Gynecol 1984; 64:395-9.