Abstract
Background: Internationally there are no defined standards for expressing the performance of home-based pregnancy tests, nor any pre-defined accuracy standard requirements. The aim of this study was to evaluate the accuracy of a selection of home-based pregnancy tests relative to their packaging/product insert claims.
Methods: Eight home-based pregnancy tests were evaluated using human chorionic gonadotrophin (hCG) urine standards (0, 15, 25 mlU/mL). Testing was performed by a technician and results were read by a technician and a panel of consumer volunteers (each blinded to the expected result) and compared with the expected result based on the manufacturer’s claimed accuracy. Volunteers also completed questionnaires relating to various device attributes.
Results: The overall agreement between the technician reading and expected reading from the hCG concentration was >90% for the Clearblue® DIGITAL, Clearblue® PLUS, Confirme® Plus, David® and Haus™ tests, and approximately 80% for Predictor® Early; agreement was <50% for Femitest® Jet Ultra and Cyclotest® Early tests. Results were available from 72 volunteers (aged 18–45 years). Overall the percentage agreement between volunteer result and expected result was >95% for Clearblue DIGITAL and Clearblue PLUS tests; agreement for all other tests was <75% (lowest were Cyclotest Early and Femitest Jet Ultra, 33.0% and 39.4%, respectively). The Clearblue DIGITAL test was scored most highly by volunteers in the questionnaires.
Conclusions: Many home-based pregnancy tests commonly used by women are not as accurate as their packaging information claims. International test standards which define appropriate performance characteristics for home pregnancy tests are urgently required.
Acknowledgments
Editorial assistance for the development of the manuscript was provided by Debra Scates of IMC Healthcare Communication, supported by SPD Development Co., Ltd.
Author contributions: All the authors have accepted responsibility for the entire content of this submitted manuscript and approved submission.
Financial support: This study was funded by SPD Development Co., Ltd., a wholly owned subsidiary of SPD Swiss Precision Diagnostics GmbH, the makers of Clearblue™ products.
Employment or leadership: S. Johnson, M. Cushion, S. Bond, S. Godbert and J. Pike are all employees of SPD Development Co., Ltd.
Honorarium: None declared.
Competing interests: Study design; the collection, analysis, and interpretation of data; the writing of the report; and the decision to submit the report for publication were conducted by the authors, all of whom are employees of the funding organisation.
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The online version of this article (DOI: 10.1515/cclm-2014-0643) offers supplementary material, available to authorized users.
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