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Table 4 Problems identified in randomized controlled trials confirmed to be at high risk of bias and methodological adjustments with no or minor cost applied

From: Avoidable waste related to inadequate methods and incomplete reporting of interventions: a systematic review of randomized trials performed in Sub-Saharan Africa

Domains Type of problem in original trial report N = 121 No. (%) Methodological adjustment Cost
Generation of randomization sequence Inappropriate randomization methods including sequence generated by some rule based on date/day of admission or on hospital or clinic record number 5 (4) Referring to a random number table;
Using a computer random-number generator
Coin tossing Shuffling cards or envelopes
Throwing dice
Drawing of lots
No cost
Allocation concealment No explicitly unconcealed procedure or unsealed or nonopaque or not sequentially numbered envelopes 10 (8) Central allocation (including telephone, web-based and pharmacy-controlled randomization) or sequentially numbered, opaque, sealed envelopes Minor
Incomplete outcome data Exclusion of patients from the analysis 14 (11) Intention-to-treat analysis No cost
Intention-to-treat analysis but inadequate missing data imputation 2 (1) Intention-to-treat analysis with a multiple imputation method Minor