A study claiming that spectacle lenses are overprescribed for children in the United States has engendered criticism from optometrists and the Vision Council of America (VCA).
The study, recently published in the Journal of the American Association for Pediatric Ophthalmology and Strabismus (AAPOS), was conducted by Sean P. Donahue, MD, PhD, at the Tennessee Lions’ Eye Center at Vanderbilt Children’s Hospital, Nashville.
“This is such a small problem compared to the real problem out there, which is that vision screenings are missing children,” said Joseph LaMountain, spokesperson for VCA. “This study doesn’t look at the bigger picture.”
The study addresses only those factors that cause amblyopia without considering visual function, said Glen T. Steele, OD, professor and chief of pediatrics and vision therapy at the Southern College of Optometry, Memphis. “A child with 2.5 D of myopia is considered normal in this study. While 2.5 D of myopia will not cause amblyopia, it will significantly impair a child’s ability to function in the classroom,” he said in an interview with Primary Care Optometry News.
Dr. Donahue maintained that the study was not intended to be inflammatory, only to explore different methods of detecting children’s visual problems. “There is more than one way to detect a child with amblyopia,” Dr. Donahue said in an interview. “One is with a mandatory eye examination; the other is with a vision screening. I looked at those two approaches.”
Details of the study
The study abstract begins by addressing the assertion that children are being prescribed unnecessary spectacles. “Legislation to require formal eye examination prior to school entry is being considered in several states and is supported by optical trade organizations,” the abstract reads. “Pediatric ophthalmologists cite anecdotal cases that suggest children receive spectacles unnecessarily, but data to support this are lacking.”
The study looked at eye examination results from children referred to local eye doctors following a statewide preschool screening program. The examination results were assessed to determine how often glasses were prescribed for children who did not have amblyogenic factors.
The study found that of 102,508 preschool children screened, 890 children did not have amblyogenic factors. Spectacles were prescribed for 174 (19.5%) of these children.
The study went on to compare the spectacle-prescribing habits of pediatric ophthalmologists with comprehensive ophthalmologists and optometrists. “Only five of 272 children (1.8%) were prescribed glasses following examination by a pediatric ophthalmologist,” the abstract stated, “while glasses were prescribed for 24 of 205 children (11.7%) examined by comprehensive ophthalmologists and 145 of 413 (35.1%) children seen by optometrists.”
The study found that 80 children were prescribed glasses for refractive error ranging from –0.75 sph to +2.00 sph, 32 of whom had spherical equivalent of 1 D or less.
The study concluded that a significant percentage of children are probably prescribed glasses unnecessarily.
Dr. Donahue said the study used established guidelines in terms of identifying “unnecessary” prescriptions. “One set was the American Academy of Ophthalmology’s (AAO’s) preferred practice patterns regarding the eye examinations for amblyopia and comprehensive pediatric eye exams,” he said.
Dr. Donahue said he also looked at the criteria that have been set up by the AAPOS for preschool vision screenings, as well as the Vision in Preschool (VIP) study. “This was a multicenter prospective study that evaluates different types of vision screening instruments,” he said. “We looked at what they considered to be an amblyogenic factor or an important target condition to detect preschool-aged children.”
Dr. Donahue said he used the most conservative of these guidelines and, in this way, determined whether children needed glasses. “We didn’t just make this up; we used guidelines that were established in the past and that were being used by most doctors who see a lot of kids,” he said. “Our guidelines were almost identical to the VIP guidelines and the AAPOS guidelines.”
Objections to study results
According to Mr. LaMountain, Dr. Donahue’s study undermines the importance of a comprehensive eye exam and overlooks more important issues.
“This study looked at 100,000 children, and they were saying that maybe 100 or 150 of them were prescribed glasses that were unnecessary. This is maybe one in 1,000 children,” he told Primary Care Optometry News.
Mr. LaMountain went on to cite another study published by Dr. Donahue in 2000 in the journal Ophthalmology. “It found that Dr. Donahue’s own screening program missed one in two children with amblyogenic factors,” Mr. LaMountain said. “So I am wondering why Dr. Donahue is so concerned with the one in 1,000 children who are prescribed ‘unnecessary’ glasses, rather than the one in two children his program is missing.”
“Our study looked only at the children who had comprehensive examinations following vision screenings,” said Dr. Donahue, “not the ones who passed the vision screenings.”
Dr. Steele said the study takes things out of context by focusing only on those factors that may cause amblyopia. “There are other reasons to prescribe glasses besides amblyopia,” he said. “We prescribe more based on visual function.”
Dr. Donahue said in his 2004 study, the children were referred following a failed vision screening, at which time they received full eye exams.
“They received a formal comprehensive eye exam by doctors who structurally examined the eye and checked the cycloplegic refractive error with dilating drops,” he said. “The data I presented were based on comprehensive eye exams by trained eye doctors.”
Dr. Donahue said he did not intend to undermine the importance of eye exams, only to explore the different methods of detecting visual problems in children. “With a traditional vision screening, there is about a 5% referral rate and an 80% positive predictive value. Most of the kids who have a vision problem will be detected,” he said. “The other children will never need to spend the money on a formal eye examination, and it saves resources for everybody, as well as manpower.”
According to Joel N. Zaba, OD, co-author of a pivotal study in Kentucky, practitioners should put more of an emphasis on the dangers of undetected visual problems in children. The Kentucky study found that nearly one in seven children examined under the state’s mandatory eye exam law needed glasses. An additional 5% were found to have had significant undiagnosed problems (Journal of Behavioral Optometry, Vol. 14, Issue 5).
“I think it would be more appropriate for our professionals to work together in realizing that there are social and emotional consequences of undetected visual problems,” he told Primary Care Optometry News. “It is important for our children, especially in regard to the visual demands of our culture. Every child entering the public school system deserves a complete vision examination.”
Dr. Donahue also acknowledged the differing opinions on this topic, adding that these opinions could be politically or financially motivated. “The mandatory eye examination legislation is being pushed primarily by Vision Council of America, which is the lobby organization for the spectacle manufacturers,” he said. “So the real story here is that the spectacle manufacturers are out to encourage mandatory eye exams.”
Mr. LaMountain said he is disappointed when he hears of attempts to discredit his organization. “I saw an editorial that accompanied this study that tried to present our organization as a big, bad group that is forcing children to wear glasses,” he said. “We don’t prescribe glasses, eye doctors do. It’s sad, pathetic and desperate.”
“Optometry is still going to prescribe glasses based on how patients function,” Dr. Steele said. “We are still going to look at the child’s ability to see the chalkboard and the child’s ability to focus on the material he or she is reading and writing. We are going to look at those things as most important and not just look at one small aspect called amblyogenic factors.”
For Your Information:
- Sean P. Donahue, MD, PhD, is associate professor of ophthalmology at Vanderbilt University. He can be reached at 8000 Medical Center East, Nashville, TN 37232; (615) 936-2020; fax: (615) 936-2118.
- Joseph LaMountain is a spokesperson for Vision Council of America. He can be reached at 1700 Diagonal Rd., Alexandria, VA 22314; (703) 548-4566; fax: (703) 548-4580; e-mail: firstname.lastname@example.org.
- Glen T. Steele, OD, is a professor and chief of pediatrics and vision therapy at the Southern College of Optometry. He can be reached at 1245 Madison Ave., Memphis, TN 38104; (901) 722-3284; fax: (901) 722-3281; e-mail: email@example.com.
- Joel N. Zaba, OD, is one of the authors of the Kentucky study. He can be reached at Pembroke One, Ste. 105, 281 Independence Rd., Virginia Beach, VA 23462; (757) 497-9575; fax: (757) 407-1292.