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Corneal Astigmatism Measurement Study

This study has been completed.
Information provided by (Responsible Party):
Alcon Research Identifier:
First received: January 6, 2009
Last updated: April 6, 2012
Last verified: July 2009
To assess which commercially available measurement device is most accurate in measuring low (< 1.0 D) degrees of corneal astigmatism.


Study Type: Observational
Study Design: Time Perspective: Prospective

Further study details as provided by Alcon Research:

Primary Outcome Measures:
  • Measurement of corneal power [ Time Frame: Day 1 ]

Enrollment: 50
Study Start Date: December 2008
Study Completion Date: April 2009
Primary Completion Date: April 2009 (Final data collection date for primary outcome measure)
Measurement device


Ages Eligible for Study:   50 Years and older   (Adult, Senior)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   Yes
Sampling Method:   Non-Probability Sample
Study Population
community sample

Inclusion Criteria:

  • 50 years of age and older
  • Proof of eye exam within the last 3 months
  • Corneal astigmatism of <1.0 diopter

Exclusion Criteria:

  • Prior history of refractive or corneal surgery
  • Corneal trauma/disease
  • Intraocular surgery
  Contacts and Locations
Choosing to participate in a study is an important personal decision. Talk with your doctor and family members or friends about deciding to join a study. To learn more about this study, you or your doctor may contact the study research staff using the Contacts provided below. For general information, see Learn About Clinical Studies.

Please refer to this study by its identifier: NCT00818532

United States, Texas
Alcon Call Center for Trial Locations
Fort Worth, Texas, United States, 76134
Sponsors and Collaborators
Alcon Research
  More Information

Responsible Party: Alcon Research Identifier: NCT00818532     History of Changes
Other Study ID Numbers: P-08-04
Study First Received: January 6, 2009
Last Updated: April 6, 2012

Keywords provided by Alcon Research:
Corneal astigmatism
Low diopter
Corneal measurement
Corneal astigmatism < 1 Diopter

Additional relevant MeSH terms:
Refractive Errors
Eye Diseases processed this record on August 18, 2017