ArticleJournal of ophthalmology2019
Wide Variation of Squeezing Force and Dispensing Time Interval among Eyedropper Bottles.
Article in Journal of ophthalmology, 2019. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 5 papers.
What it found
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The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.
The trial behind it
Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.
Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.
Who cites it
5 citing papers in PubMed, 9 citations in OpenAlex.
- Investigation of visual and physical factors associated with inadequate instillation of eyedrops among patients with glaucoma.PloS one · 2021Trial
- Effectiveness of a Newly Developed Instillation Aid for Unit-Dose Ophthalmic Solutions.Journal of clinical medicine · 2025Article
- Optimizing instilled drug delivery: a scoping review of microdrops in ophthalmology.Graefe's archive for clinical and experimental ophthalmology = Albrecht von Graefes Archiv fur klinische und experimentelle Ophthalmologie · 2025Article
- Article
- Artificial Tears: A Systematic Review.Clinical optometry · 2023Review
Corrections and comments
PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.
Authors and funding
1 author at 1 institution in 1 country.
Funding
No grant is acknowledged in the PubMed record.
Abstract
purposeWe aimed to investigate squeezing force and dispensing time interval of the first and second eye drops among a variety of eyedropper bottles and to clarify associated factors within these parameters.
methodsA total of 87 eyedropper bottles were involved in this study. We developed a squeezing force measuring system consisting of a syringe pump, digital force gauge, and custom-made test stand to measure the squeezing force and dispensing interval. The eyedropper bottle was housed in the system vertically, and measurements were repeated five times. We investigated the differences in squeezing force and dispensing interval by categories, including those that targeted ocular disease, brand or generic eyedroppers, shapes of eyedropper bottles, and the presence of a membrane filter inside the tip of the eyedropper bottle.
resultsThe mean squeezing forces of the first drop and the second drops were 8.3 ± 3.0 N and 10.4 ± 3.2 N, respectively. Both squeezing forces had a wide variation of more than threefold. A mean interval between the first and second drops was 3.1 ± 1.2 sec with a maximum difference of more than sevenfold. Round shapes of eyedropper bottles and the presence of filter membranes significantly increased the squeezing force.
conclusionsThe squeezing force of eyedropper bottles was very wide, which may affect proper eye drop instillation. Unification of eyedropper bottles or developing mechanical aids may be useful for proper eye drop treatment.
Identifiers
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Registered trials
Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.