Buzzonetti 2008.

Study characteristics
Methods	Study design: randomized controlled trial Study grouping: parallel group Number randomly assigned: 47 eyes, 28 participants Exclusions after randomization: not reported Number analyzed: not reported Unit of analysis: eye Losses to follow‐up: not reported Handling of missing data: not reported Power calculation: "Given the expected difference between the mean aberration values of 20% and the expected SD from the mean value for each group of 20%, the sample size considered in this trial (n = 24 eyes in the mechanical microkeratome group and n = 23 eyes in femtosecond laser group) provided a power of 85% at a level of 0.02." Study dates: June 2004 to November 2005
Participants	Country: Italy Overall mean age: 38.7 years (SD 9.8) Age range: not reported Gender: not reported Setting: Institute of Ophthalmology, Catholic University, Rome Equivalence of baseline characteristics: yes Inclusion criteria: people with spherical and spherocylindrical myopia, preoperative astigmatism value 2.00 D and mean spherical equivalent defect of –5.2 D (SD 3.3) Exclusion criteria: not reported
Interventions	Laser for ablation: Bausch & Lomb Technolas 217 excimer laser Intervention 1 Intervention: LASIK with a Hansatome microkeratome Flap dimensions: 160 μm thickness, 9.0 mm diameter, superior hinge Number of people randomized: 24 eyes, 15 participants Length of follow‐up: Planned: not reported Actual: 12 months Intervention 2 Intervention: LASIK with an IntraLase femtosecond laser Flap dimensions: 120 μm thickness, 9.0 mm diameter, and 50 degree, superior hinge angle Number of people randomized: 23 eyes, 13 participants Length of follow‐up: Planned: not reported Actual: 12 months
Outcomes	Mean UCVA after surgery Intervals at which outcome assessed: 1 month Planned follow‐up: not reported Actual follow‐up: 12 months Scale: not reported Instrument for measurement: not reported BCVA after surgery Intervals at which outcome assessed: 1 month Planned follow‐up: not reported Actual follow‐up: 12 months Scale: not reported Instrument for measurement: not reported Mean spherical equivalent of the refractive error after surgery Intervals at which outcome assessed: 1 month Planned follow‐up: not reported Actual follow‐up: 12 months Scale: D Instrument for measurement: not reported Adverse events reported: no
Identification	Sponsorship source: IRCCS‐Casa Sollievo della Sofferenza Hospital ans Institue of Ophthalmology of Catholic University Country: Italy Setting: Institute of Ophthalmology Comments: none Author's name: Luca Buzzonetti Institution: Ophthalmology Department, IRCCS–Casa Sollievo della Sofferenza Hospital, Institute of Ophthalmology, Catholic University Email: lbuzzonetti@ tibernet.it Address: Via Sabotino, 2‐00195 Rome, Italy
Notes	Trial registration number: not reported
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	Quote: "patients were randomly assigned to either the mechanical microkeratome or IntraLase." Comment: randomization method not specified
Allocation concealment (selection bias)	Unclear risk	Comment: allocation concealment not specified
Blinding of participants and personnel (performance bias) All outcomes	Unclear risk	Comment: no clear description of the measures used to mask trial participants and personnel from knowledge of which intervention a participant received
Blinding of outcome assessment (detection bias) All outcomes	Unclear risk	Comment: no description of the measures used to mask outcome assessors from knowledge of which intervention a participant received
Incomplete outcome data (attrition bias) All outcomes	Unclear risk	Comment: unclear whether all participants randomized were also analyzed
Selective reporting (reporting bias)	Unclear risk	Comment: no published trial protocol with which to compare
Other bias	Low risk	Comment: trial appeared free of other sources of bias