Dapling 1994.

Methods	Study design: parallel‐group RCT Country: England Number randomized: Total: 75 eyes Per group: apraclonidine = 26 eyes, pilocarpine = 23 eyes, apraclonidine/pilocarpine = 26 eyes Exclusions after randomization: none reported Number analyzed: Total: 75 eyes Per group: apraclonidine = 26 eyes, pilocarpine = 23 eyes, apraclonidine/pilocarpine = 26 eyes Unit of analysis: eyes, if both eyes required LTP, then the first eye to be treated was entered into the study. Losses to follow‐up: none reported How was missing data handled?: N/A Reported power calculation: no Unusual study design (any issues with study design)?: none
Participants	Age (mean (range); years): apraclonidine = 72.2 (53 to 84), pilocarpine = 68.4 (53 to 86), apraclonidine/pilocarpine = 71.3 (46 to 87) Females: not reported Inclusion criteria: OAG with in IOP > 21 mmHg Exclusion criteria: regular pilocarpine to either eye, active ocular infection or inflammation present, unstable cardiovascular disease, taking systemic clonidine Equivalence of baseline characteristics: yes, "There was no statistically significant difference between the groups with respect to age, eye color, type of glaucoma, or glaucoma medication. All patients had similar disease as judged by single medication, duration of disease, and cumulative treatment."
Interventions	Intervention 1: 1 drop apraclonidine 1% 1 hour before and 1 drop immediately after 180° ALT Intervention 2: 1 drop pilocarpine 4% immediately after 180° ALT Intervention 3: 1 drop of apraclonidine 1%, 1 hour before and 1 drop of apraclonidine 1%/1 drop of pilocarpine 4%, immediately after 180° ALT Length of follow‐up: Planned: 1 week Actual: 1 week
Outcomes	Primary outcome: IOP Secondary outcomes: heart rate, BP Adverse events reported: no Intervals at which outcomes assessed: baseline; 1, 2, 3 hours; 1 week following trabeculoplasty
Notes	Trial registration: not reported Funding sources: Alcon Laboratories in England supported the study Disclosures of interest: no disclosures reported Study period: not reported Reported subgroup analyses: no
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	"Patients were then randomly allocated to one of the three treatment groups." Did not state how the sequence was generated.
Allocation concealment (selection bias)	Unclear risk	Allocation concealment not reported.
Masking of participants and personnel (performance bias)	High risk	Masking of participants and personnel not reported but due to the nature of the interventions, participants would know whether or not they got medication before or after the surgery and that they received 2 drops of medication if in the combination group.
Masking of outcome assessment (detection bias)	Low risk	"The observer was masked to the study group of the patient."
Incomplete outcome data (attrition bias) All outcomes	Low risk	Data available for all participants who were randomized.
Selective reporting (reporting bias)	Unclear risk	Unclear whether there was selective outcome reporting.
Other bias	High risk	Supported by Alcon Laboratories, which makes products containing apraclonidine and pilocarpine. Additionally, a difference drop regimen without use of vehicle drops would leave participants essentially unmasked.