Page 52 - ESHRE2019

Block randomisation
• The smaller the block the more balanced the groups BUT the more predictable the sequence
• Overused technique, unnecessary in large trials
• “Block randomisation” only is not enough for low-risk
Allocation concealment
If an open label (unblinded) trial
• What block size/s were used?
• Were at least two block sizes used and randomly repeated?
• Was randomisation stratified by site?
• Did the researchers allocating patients know the block
size?
2. Allocation concealment
“We randomised patients using an independent telephone randomisation +- system”
Random selection to either group was performed by drawing a piece of paper from the bag containing equal number of printed paper for each method
?
5 The random allocation of patients into two groups was carried out using random +- allocation software that included a minimisation algorithm balancing sex and age.
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The treatment allocation was done using closed sealed envelope by an assigned nurse before the hysteroscopy
4 The sequence of randomisation was concealed until intervention assigned ?
6 Patients were randomised at the time of the operation by flipping a coin
7 Block randomisation with blocks of two
Participants were randomised using sequentially numbered opaque sealed envelopes
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