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I thank Kulvichit for their response[1] to my endgame on block randomisation[2]. Kulvichit is correct that answers a and c are only true if the trial participants are allocated in equal numbers i.e. an allocation ratio of 1:1 within the blocks.
The allocation ratio of trial participants is often not reported for clinical trials. It would appear it is assumed the allocation ratio is 1:1 unless otherwise specified. The question that Kulvichit’s response raises is whether such an assumption is intuitive?
References
1. Kulvichit K. Re: Block randomisation. 11th November 2011.
2. Sedgwick P. Block randomisation. BMJ 2011;343:bmj.d7139.
Re: Block randomisation
I thank Kulvichit for their response[1] to my endgame on block randomisation[2]. Kulvichit is correct that answers a and c are only true if the trial participants are allocated in equal numbers i.e. an allocation ratio of 1:1 within the blocks.
The allocation ratio of trial participants is often not reported for clinical trials. It would appear it is assumed the allocation ratio is 1:1 unless otherwise specified. The question that Kulvichit’s response raises is whether such an assumption is intuitive?
References
1. Kulvichit K. Re: Block randomisation. 11th November 2011.
2. Sedgwick P. Block randomisation. BMJ 2011;343:bmj.d7139.
Competing interests: No competing interests