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38. SPD data on file: Agreement between the gestational age results obtained using the Clearblue Pregnancy Test with Weeks Indicator compared to
ultrasound CRL–based measurements converted using the Robinson formula was 95.5%, 94.6%, 100.0% and 98.0% for 1-2 weeks, 2-3 weeks, 3+ weeks
and overall, respectively.
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40. Johnson S, et al. Agreement between the Clearblue Digital Pregnancy Test Conception Indicator and standard-of-care ultrasound dating in the
assessment of pregnancy duration. Curr Med Res Opin. (2011) 27: 393–401.
41. Johnson SR, et al. Levels of urinary human chorionic gonadotrophin (hCG) following conception and variability of menstrual cycle length in a cohort of
women attempting to conceive. Curr Med Res Opin. (2009) 25: 741–748.
42. SPD data on file: Analysis of a combined dataset from 143 women from the US Gestational Ages study
22
and 44 women from the UK Standard-of-Care
23
study reported high-level agreement (97%) between Clearblue Pregnancy Test with Weeks Indicator and ultrasound dating scan results.
43. Johnson S, Godbert S. Comparison of home pregnancy test with weeks estimator and ultrasound crown rump measurement to predict delivery date.
Fertil Steril. (2013) 100: S330.
44. Johnson S. Home pregnancy test and urinary hCG compared to ultrasound assessment of pregnancy duration. 1
st
International Conference of Obstetrics
Gynecology, Guangzhou, China. (2012) Abstract and Oral Presentation.
45. Pike J, et al. Comparison of volunteers’ experience of using, and accuracy of reading, different types of home pregnancy formats. Expert Opin Med Diagn.
(2013) 7: 435–441.
46. SPD data on file: In a study of 114 consumers, 93.8% rated their confidence in the result of the Clearblue Pregnancy Test with Weeks Indicator as 1–3 on a 7
point scale (1=very confident; 7=not very confident).
47. Tomlinson C, et al. Comparison of accuracy and certainty of results of six home pregnancy tests available over-the-counter. Curr Med Res Opin.
(2008) 24: 1645–1649.
48. SPD data on file: In a study of 114 consumers, 92.1% stated they were more likely to use a pregnancy test with a Weeks Indicator feature than a standard
pregnancy test.
49. Stenman UH, et al. The classification, functions and clinical use of different isoforms of HCG. Hum Reprod Update. (2006) 12: 769–784.
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