Design, Evaluation, and Dissemination of a Plastic Syringe Clip to Improve Dosing Accuracy of Liquid Medications


Pediatricians in Africa requested a tool to improve caregiver dosing of liquid antiretroviral medication. We developed, evaluated and disseminated a clip to control the amount of medication drawn into an oral syringe. In a laboratory, a user tested clips of different lengths, corresponding to different volumes, by drawing water into a syringe with a clip. In Texas and Malawi, 149 adults attempted to measure Pepto-Bismol™ using a syringe with a clip, a syringe without a clip, and a dosing cup, in a randomly assigned order. In the laboratory, the volume of liquid, ranging from 1 to 4.5 mL, drawn into the syringe was always within at least 5 μL of the intended dose. In Texas, 84% of doses were accurate within ±10%, vs. 63% using the syringe alone, and 21% with the dosing cup. In Malawi, 98% of doses were accurate to within ±10%, vs. 90% using the syringe alone, and 27% with the dosing cup. For target accuracy values within ±45% (±21%), a significantly higher fraction of Houston (Kamangira) participants delivered an accurate dose using the syringe with the clip than with the syringe alone (p < 0.05). The clip enables a greater proportion of users to accurately measure liquid medication.

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This work was supported in part by a grant to Rice University from the Howard Hughes Medical Institute through the Undergraduate Science Education Program.

Conflict of interest

Drs. Richards-Kortum, Oden, Ms. Dinh, Ms. Gutierrez, and Ms. Lukomnik submitted a patent application for the dosing clip described in this paper. Drs. Richards-Kortum and Oden have waived their financial interest in this patent.

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Correspondence to Rebecca Richards-Kortum.

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Associate Editor John Desjardins oversaw the review of this article.

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Spiegel, G.J., Dinh, C., Gutierrez, A. et al. Design, Evaluation, and Dissemination of a Plastic Syringe Clip to Improve Dosing Accuracy of Liquid Medications. Ann Biomed Eng 41, 1860–1868 (2013).

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  • Dosing error
  • Measuring devices
  • Medication administration
  • Medication errors
  • Global health
  • Low-resource settings