Biomaterial Database

Spectacle-use, bifocals and prevention of myopic progression. The two-years results of a randomized trial among schoolchildren. 1988

O Pärssinen, and E Hemminki

This paper gives the two-year follow-up results of a randomized trial of three different types of corrective lenses: 1) minus lenses with full correction for continuous use (the Reference group); 2) minus lenses with full correction to be used for distant vision only; and 3) bifocal lenses. A total of 240 9-11-years old mildly myopic schoolchildren were randomly allocated to the three different treatment groups to be followed up for 3 years. After 2-years follow-up the change in the spherical equivalent was greatest in the distant use group. There were no significant positive correlations between changes in refraction and accommodation or refraction and convergence.

UI	MeSH Term	Description	Entries
D008297	Male		Males
D009216	Myopia	A refractive error in which rays of light entering the EYE parallel to the optic axis are brought to a focus in front of the RETINA when accommodation (ACCOMMODATION, OCULAR) is relaxed. This results from an overly curved CORNEA or from the eyeball being too long from front to back. It is also called nearsightedness.	Nearsightedness,Myopias,Nearsightednesses
D011897	Random Allocation	A process involving chance used in therapeutic trials or other research endeavor for allocating experimental subjects, human or animal, between treatment and control groups, or among treatment groups. It may also apply to experiments on inanimate objects.	Randomization,Allocation, Random
D012029	Refraction, Ocular	Refraction of LIGHT effected by the media of the EYE.	Ocular Refraction,Ocular Refractions,Refractions, Ocular
D002648	Child	A person 6 to 12 years of age. An individual 2 to 5 years old is CHILD, PRESCHOOL.	Children
D002986	Clinical Trials as Topic	Works about pre-planned studies of the safety, efficacy, or optimum dosage schedule (if appropriate) of one or more diagnostic, therapeutic, or prophylactic drugs, devices, or techniques selected according to predetermined criteria of eligibility and observed for predefined evidence of favorable and unfavorable effects. This concept includes clinical trials conducted both in the U.S. and in other countries.	Clinical Trial as Topic
D003290	Convergence, Ocular	The turning inward of the lines of sight toward each other.	Convergences, Ocular,Ocular Convergence,Ocular Convergences
D005139	Eyeglasses	A pair of ophthalmic lenses in a frame or mounting which is supported by the nose and ears. The purpose is to aid or improve vision. It does not include goggles or nonprescription sun glasses for which EYE PROTECTIVE DEVICES is available.	Glasses,Spectacles,Sun Glasses, Prescription,Glasses, Prescription Sun,Prescription Sun Glasses
D005260	Female		Females
D005500	Follow-Up Studies	Studies in which individuals or populations are followed to assess the outcome of exposures, procedures, or effects of a characteristic, e.g., occurrence of disease.	Followup Studies,Follow Up Studies,Follow-Up Study,Followup Study,Studies, Follow-Up,Studies, Followup,Study, Follow-Up,Study, Followup