Sample size calculation and randomization
The sample size was not calculated because accurate data on the
prevalence of cognitive decline in older patients with moderate hearing
loss are lacking.
The main author randomized the patients into three groups – A, B, and C
– in a 1:1:1 ratio, using the Randomizer for Clinical Trials tool
developed at the Medical University of Graz [28]. After random
selection, the numbers and their respective groups were placed in opaque
envelopes and sealed. Envelopes were opened at the time of selection of
the hearing instruments to be fitted and the patients were blinded to
their group allocation. Patient sequence, allocation, and treatment were
carried out by the researchers.