Adrait 2017.

Methods	2‐arm, double‐blinded, multi‐centre, with 6 months duration of treatment and follow‐up
Participants	Location: France, multi‐centre sites Setting of recruitment and treatment: hospital setting Sample size: Number randomised: 51*, 48 fitted with hearing aids (22 intervention, 26 control) Number completed: 38 (18 in intervention, 20 in comparison; attrition n = 10 (20.8%), caregiver withdrawal n = 1, caregiver or legal representative withdrawal n = 2, voluntary withdrawal n = 3, investigator exclusion n = 1, protocol deviation n = 2, serious adverse event not related to the trial n = 1). *n = 3 not fitted, 2 in active group, 1 in placebo group (erroneously included (unilateral hearing loss) n = 1, voluntary withdrawal n = 2) Participant (baseline) characteristics: Age: intervention, mean 83.0 years (SD 6.2); control, mean 82.3 years (SD 7.2) Gender: intervention, 8 male, 14 female; control, 11 male, 15 female Main diagnosis: hearing loss (pure‐tone average (PTA) averaged across 0.5, 1.0, 2.0, 4.0 kHz; bilateral): intervention 50.6 dB HL (SD 11.4); control mean 47.2 dB HL (SD 9.6) Other important effect modifiers: all patients had Alzheimer's disease (see inclusion criteria) Inclusion criteria: probable diagnosis of AD according to DSM‐IV and NINCDS‐ADRDA, aged >= 65 years, Mini‐Mental State Examination score between 10 and 28, bilateral SNHL (between 21 and 80 dB HL), not worn hearing aids for previous 2 years, tolerates hearing aids for at least 1 hour per day, living with an informal, motivated caregiver. Exclusion criteria: non‐AD dementia (medical history, clinical elements, biological/medical imaging data examples given), recent introduction of cognitive‐behavioural treatment, change in dosage of treatments prior to the study (cholinergic and memantine (< 6 m), psychotropic medication (< 2 m)), recent change in dosage of treatments (cholinergic and memantine (< 2 m), (cholinergic and memantine (< 1 m)), break or loss of hearing aids 2 or more times during study.
Interventions	Intervention group (n = 18): active hearing aids (SAVIA and VALEO (Phonak), behind‐the‐ear, fully digital, bilateral fits. Fitted according to Phonak Digital (proprietary fitting algorithm derived from NAL‐NL1). Comparator group (n = 20): placebo hearing aids, programmed to minimal amplification so patients could just hear 25 dB SL white noise (30 dB on average), to compensate for the occlusion effect. Use of additional interventions (common to both treatment arms): at 6 months, placebo hearing aids were activated; both groups used active hearing aids for 12 months study endpoint.
Outcomes	Primary outcome: Neuropsychiatric Inventory Secondary outcomes: Instrumental Activities of Daily Living, Zarit, Alzheimer Disease Related Quality of Life, Duke health profile (simplified, items 15 and 16 on social interactions) for patient and caregiver. Adverse effects. None of these outcome measures were relevant or appropriate to the outcome domains of interest specified in this review.
Funding sources	French Ministry of Health (Clinical Research Hospital Program 2005, PHRC 2005‐APN) and the Fondation Mederic Alzheimer, Paris
Declarations of interest	Nothing to disclose
Notes	All participants had a probable diagnosis of Alzheimer's disease and so this was a distinctly different clinical population from typical first‐time hearing aid users. Hearing aids provided by Phonak at no cost to the participant.
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	Randomisation used a pre‐established and well‐balanced list based on chronological order of inclusion. Used blocks of 6 patients.
Allocation concealment (selection bias)	Low risk	Randomisation procedure was centralised at a clinical research unit remote from the study setting and conducted by research methodologists independent of the study team.
Blinding of participants and personnel (performance bias) All outcomes	Low risk	Placebo hearing aids used so participants were blinded. Only the hearing aid specialist fitting the devices knew the randomisation group of the participants (required to apply the appropriate gain prescription). Unlikely that blinding could be broken.
Blinding of outcome assessment (detection bias) All outcomes	Low risk	Outcome assessor and participants were blinded.
Incomplete outcome data (attrition bias) All outcomes	Unclear risk	Dropouts and withdrawals were documented but unclear why some data from the remaining participants on some outcomes were not reported.
Selective reporting (reporting bias)	Low risk	Data on all outcomes in the published study protocol (NCT01788423) were reported.
Other bias	Low risk	Study appears to be free of other sources of bias.