Author Affiliation: Duke Eye Center, Durham, North Carolina.
In the article by Dr Zhao and colleagues1 on acupuncture for amblyopia, it is unclear how long subjects actually wore optimal spectacles prior to randomization to patching or acupuncture. This issue is important because studies have shown that spectacles alone are a powerful treatment for amblyopia.2 - 4 The authors wrote that, “At a screening visit, protocol-specified spectacles were prescribed. . . The baseline examination was scheduled within 2 weeks of the screening visit. New spectacles were provided for all participants on the day of the baseline examination. . . With the participants wearing the new spectacles, VA (visual acuity) was measured in each eye. . . The better of the 2 VA scores was used as the baseline VA to assess eligibility. . . After eligibility was confirmed, participants were randomly assigned. . . Treatments were started within 2 days after randomization.” So it seems that subjects were given new spectacles and randomized within 2 days of receiving them. If so, this is inconsistent with the authors' statement that “Patients were eligible if they had worn optimal spectacles for at least 16 weeks prior to enrollment,” and “The spectacles should have been worn until VA was stabilized.” The spectacles should have been or were actually worn for at least 16 weeks? If many subjects were randomized before visual acuity stopped improving with spectacles, I am not surprised that both patching and acupuncture groups had robust improvement. In an equivalence study (unlike a superiority study), factors such as new spectacles or a recent change in spectacles that predispose to improvement in both groups will bias toward supporting the study hypothesis (in this case, equivalence between patching and acupuncture).
In addition, I am concerned that the disparate frequency of contact with office staff may have affected the primary outcome (visual acuity) in this study. During the 15 weeks between baseline and the primary outcome measure, the patching group had 3 total office visits, whereas the acupuncture group had 5 visits per week, or 75 total visits. Frequent office visits can increase a child's comfort level when performing tests such as outcome visual acuity, and it can also lead to better compliance with concurrent study treatments of spectacles wear and near activities.
Finally, I think that the felt patches prescribed for the patching group were not the best choice for this trial. The fact that “No parent reported at any visit that their child had performed less than 2 hours of patching at any time” does not mean that the child did not spend a good deal of time looking over or around the both the patch and spectacles.
Correspondence: Dr Wallace, Duke Eye Center, Box 3802, Durham, NC 27710 (david.wallace@duke.edu).
Financial Disclosure: Dr Wallace reports receiving funding from the National Eye Institute in his role as Vice Chair of the Pediatric Eye disease Investigator Group, which performs randomized trials in amblyopia.
Country-Specific Mortality and Growth Failure in Infancy and Yound Children and Association With Material Stature
Use interactive graphics and maps to view and sort country-specific infant and early dhildhood mortality and growth failure data and their association with maternal
Instructions
Comments are moderated and will appear on the site at the discretion of the Archives of Ophthalmology editors. Comments should not exceed 500 words of text and 10 references.
Do not submit personal medical questions or information that could identify a specific patient, questions about a particular case, or general inquiries to an author. Only content that has not been published, posted, or submitted elsewhere should be submitted. By submitting this Comment, you and any coauthors transfer copyright to the journal if your Comment is posted.
* = Required Field
Disclosure of Any Conflicts of Interest* Indicate all relevant conflicts of interest of each author below, including all relevant financial interests, activities, and relationships within the past 3 years including, but not limited to, employment, affiliation, grants or funding, consultancies, honoraria or payment, speakers’ bureaus, stock ownership or options, expert testimony, royalties, donation of medical equipment, or patents planned, pending, or issued. If all authors have none, check "No potential conflicts or relevant financial interests" in the box below. Please also indicate any funding received in support of this work. The information will be posted with your response.
Register and get free email Table of Contents alerts, saved searches, PowerPoint downloads, CME quizzes, and more
Subscribe for full-text access to content from 1998 forward and a host of useful features
Activate your current subscription (AMA members and current subscribers)
Some tools below are only available to our subscribers or users with an online account.
Download citation file:
Customize your page view by dragging & repositioning the boxes below.
and access these and other features:
Register Now
Enter your username and email address. We'll send you a reminder to the email address on record.
Athens and Shibboleth are access management services that provide single sign-on to protected resources. They replace the multiple user names and passwords necessary to access subscription-based content with a single user name and password that can be entered once per session. It operates independently of a user's location or IP address. If your institution uses Athens or Shibboleth authentication, please contact your site administrator to receive your user name and password.