Jampel HD, Chon BH, Stamper R, et al. Effectiveness of Intraocular Pressure–Lowering Medication Determined by Washout. JAMA ophthalmology 2014;132(4):390-95.
PubMed link: https://www.ncbi.nlm.nih.gov/pubmed/24481483
Full text article: https://jamanetwork.com/journals/jamaophthalmology/fullarticle/1815983
| Methods | Study design: Before-and-after study as a lead-up to a randomized controlled study
Number of groups: One group |
| Participants | Number of participants: 603 enrolled
Age: 70.3 ± 8.1 years Sex: 334 female, 269 male Participants with dementia: No Inclusion criteria: · Mild to moderate primary open angleglaucoma diagnosis with a mean deviation score of−12.0 or greater to less than 0 dB · Presence of operable cataract · Intraocular pressure not exceeding 33 mm Hg with 0 to 3 intraocular pressure-lowering medications · No minimum intraocular pressure cut-off used for enrollment · Fixed combination medications, such as a topical carbonic anhydrase inhibitor and a β-adrenergic antagonist, were counted as two medications Exclusion criteria: · Presence of angle closure, grade 1 or 2 by Shaffer classification · Secondary open angle pressure · Uveitic and neovascular glaucoma · Any other discernible congenital anomalies of the anterior chamber and angle, including presence of other ocular pathology,judged significant by discretion of the investigator Country: United States Setting: Community |
| Interventions | Medicine:Prostaglandin analog, β-Adrenergic antagonist, Carbonic anhydrase inhibitor, α-Adrenergic agonist
Withdrawal schedule: Not described |
| Outcomes | Difference between intraocular pressure OFF medication and intraocular pressure ON medication |
| Dates | Dates: Not stated
Follow-up duration: 5 to 28 days “The wash-out period was a minimum of 5 days for carbonic anhydrase inhibitors, 14 days for α-adrenergic agonists, and 28 days for all other medications. “At the discretion of study investigators, a subset of patients (n = 11) received brinzolamide during the wash-out period; these patients were excluded from this analysis.” |
| Funding sources | Funding/Support:Mr. Chon was supported by a research grant from Transcend Medical.
Role of the Sponsor: Transcend Medical had no role in the design and conduct of the study; collection, management, analysis, and interpretation of the data; preparation, review, or approval of the manuscript; and decision to submit the manuscript for publication. |
| Notes |
Risk of bias table
| Bias | Authors’ judgment | Support for judgment |
| Random sequence generation (selection bias) | High risk | This is the pre-randomizationrun-in phase to the study.
However: “If both eyes qualified for the study, a random number generator was used to designate the study eye.” |
| Allocation concealment (selection bias) | High risk | Not concealed – a single group for run-in. |
| Blinding of participants and personnel (performance bias) | 1 out of 5 | Open study |
| Blinding of outcome assessment (detection bias) | 1 out of 5 | Open study |
| Incomplete outcome data (attrition bias) | 1 out of 5 | Short duration observational study as a lead in to the main study – attrition was insignificant |
| Selective reporting (reporting bias) | Unclear risk | “At the discretion of study investigators, a subset of patients (n = 11) received brinzolamide during the wash-out period; these patients were excluded from this analysis.”
Excluding their data makes it hard to ascertain whom this intervention is appropriate for, although it was presumably done for the safety of this subset of participants. It is unclear how this subset was identified. |
| Confounding (non-randomized) | 5 out of 5 | There was no current control group. |
| Other bias | Low risk | |
| Newcastle-Ottawa scale | ||
| Selection bias | Representativeness of the exposed cohort | Truly representative of the average older adult with uncomplicated open angel glaucoma. |
| Selection of the non-exposed cohort | No description of the derivation of the non-exposed cohort as it is a before-and-after study | |
| Ascertainment of exposure | No description | |
| Demonstration that outcome of interest was not present at start of study | Yes | |
| Comparability bias | Comparability of cohorts on the basis of the design or analysis | Not applicable – before-and-after study |
| Outcome bias | Assessment of outcome | Record linkage |
| Was follow-up long enough for outcomes to occur | Unclear, perhaps | |
| Adequacy of follow-up of cohorts | Complete follow-up – all subjects accounted for | |
Leave a Reply