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. 2017 Feb 23;2017(2):CD010746. doi: 10.1002/14651858.CD010746.pub2

Barnes 1999.

Methods Study design: parallel‐group RCT
Country: US
Number randomized:
Total: 56 eyes of 41 participants
Per group: brimonidine = 29 eyes, apraclonidine = 27 eyes
Exclusions after randomization: 10/15 participants who required bilateral ALT had randomization to receive the identical medication for each eye, and for these participants, only the first eye was included in the study.
Number analyzed:
Total: 46 eyes of 41 participants
Per group: brimonidine = 23 eyes, apraclonidine = 23 eyes
Unit of analysis (participants vs eyes): eyes
Losses to follow‐up: none reported
How was missing data handled?: N/A
Reported power calculation: yes, power of 80%
Unusual study design (any issues with study design)?: the unit of measurement was the eye and not the participant. The second eye was treated 2 to 6 weeks after the first.
Participants Age (mean; years): brimonidine = 69.9, apraclonidine = 62.4
Females: brimonidine = 48%; apraclonidine = 30%
Inclusion criteria: aged ≥ 21 years with diagnosis of POAG, pigmentary glaucoma, pseudoexfoliation syndrome, or ocular hypertension. Participants had IOP too high for their level of optic nerve cupping, no glaucoma medications were used 12 to 24 hours before ALT
Exclusion criteria: people with active ocular inflammation, contraindications to treatment with alpha‐agonists, or known hypersensitivities to alpha‐agonists, women of childbearing potential, current use of either of the study medications, previous experience with ALT
Equivalence of baseline characteristics: no statistical difference in the baseline IOP levels, number of laser applications, or energy level used in either group. Statistically significant difference in mean age (P = 0.008) of each group and the distribution of gender in each group; however, these were likely not clinically significant differences.
Interventions Intervention 1: brimonidine 0.2%, 30 to 45 min before and immediately after 360° ALT
Intervention 2: apraclonidine 1.0%, 30 to 45 min before and immediately after 360° ALT
Length of follow‐up:
Planned: 4 hours after surgery
Actual: 4 hours after surgery
Outcomes Primary outcome: maximum IOP change (from baseline to the highest postoperative IOP)
Secondary outcomes: none reported
Adverse events reported: no
Intervals at which outcomes assessed: baseline; 1, 2, and 4 hours after ALT
Notes Trial registration: not reported
Funding sources: research grant provided by Allergan, Inc
Disclosures of interest: "The authors have no proprietary interest in the products described in this study."
Study period: not reported
Reported subgroup analyses: no
Risk of bias
Bias Authors' judgement Support for judgement
Random sequence generation (selection bias) Low risk "A random‐number generator assigned patients to a treatment group before ALT."
Allocation concealment (selection bias) Unclear risk Allocation concealment not reported.
Masking of participants and personnel (performance bias) Low risk "Both patient and physician were masked as to which agent the patient received" "…and a technician would give the appropriate medication without the physician or patients' knowledge."
Masking of outcome assessment (detection bias) Unclear risk Details about outcome assessors not reported.
Incomplete outcome data (attrition bias) 
 All outcomes Low risk Some participants' randomization caused them to receive the same medication for each eye, so only the first eye was included in the study to account for the intra‐dependability of eyes and to prevent skewed results.
Selective reporting (reporting bias) Unclear risk Unclear whether there was selective outcome reporting.
Other bias High risk Study reported a research grant provided by Allergan, Inc, which makes the brimonidine 0.2% ophthalmic solution.