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.