Article type
Year
Abstract
Introduction: The validity of systematic reviews depends on the quality of the randomized controlled trials (RCTs) included. Review of the state-of-the-art of RCTs in a discipline provides feedback to those in the area as to the overall acceptability of trials available for systematic reviews.
Objective: To assess the state-of-the-art of ophthalmology RCTS.
Methods: Eight ophthalmology journals were handsearched for RCTs published from 1988 to 1994. Reports that did not include patient data or only described study methods were excluded. RCT design characteristics were extracted using a pre-tested form. Multiple RCTs within a single report were analyzed separately and data from multiple reports emanating from a single RCT were combined on a single form.
Results: We found 527 RCTs; 97% (510/527) were randomized and 3% (17/527) used quasi-randomization. Inclusion criteria were reported in 97%, and exclusion criteria in 75% of RCTs. The method of randomization allocation concealment was reported in 213 RCTs (40%) and included: lists (12%), numbered bottles (10%), sealed envelopes (5%), telephone to central facility (3%), and other (10%). Stratification was reported in 13%, and blocking in 6% of trials. Masking was reported in 72% of RCTS: 51% masked patients; 47% persons delivering treatment; 68% persons measuring outcome; and 3% persons analyzing results. Reports included data from all randomized patients in analyses 55% (292/527) of the time. There were 235 reports that did not contain complete data on all patients, either because data were not available (99/235; 42%) or because data were excluded from the analysis (136/235; 58%).
Discussion: Investigators of ophthalmology RCTs usually report masking, but infrequently report methodology related to randomization or use of intention-to-treat analyses when patients are lost to follow-up.
Objective: To assess the state-of-the-art of ophthalmology RCTS.
Methods: Eight ophthalmology journals were handsearched for RCTs published from 1988 to 1994. Reports that did not include patient data or only described study methods were excluded. RCT design characteristics were extracted using a pre-tested form. Multiple RCTs within a single report were analyzed separately and data from multiple reports emanating from a single RCT were combined on a single form.
Results: We found 527 RCTs; 97% (510/527) were randomized and 3% (17/527) used quasi-randomization. Inclusion criteria were reported in 97%, and exclusion criteria in 75% of RCTs. The method of randomization allocation concealment was reported in 213 RCTs (40%) and included: lists (12%), numbered bottles (10%), sealed envelopes (5%), telephone to central facility (3%), and other (10%). Stratification was reported in 13%, and blocking in 6% of trials. Masking was reported in 72% of RCTS: 51% masked patients; 47% persons delivering treatment; 68% persons measuring outcome; and 3% persons analyzing results. Reports included data from all randomized patients in analyses 55% (292/527) of the time. There were 235 reports that did not contain complete data on all patients, either because data were not available (99/235; 42%) or because data were excluded from the analysis (136/235; 58%).
Discussion: Investigators of ophthalmology RCTs usually report masking, but infrequently report methodology related to randomization or use of intention-to-treat analyses when patients are lost to follow-up.