Table 3.

Characteristics of articles comprising cognitive interventions

Study, country	Type of study and economic evaluation	Time horizon C: Cost H: Health outcome	Study population, Number of participants	IG: Intervention group CG: Control group	Outcome measures (measures of benefit)	Cost data; source	Perspective	Results
Orgeta [27] UK, 2015	RCT CEA CUA	C: 26 weeks H: 26 weeks	Community-dwelling PwDs of any type (MMSE ≥10) and family caregivers ▪ 356 randomized dyads ▪ 273 dyads completed the second-follow-up (76.7%) ▪ 264 dyads with complete case information for the cost analyses	IG: Home-based individual cognitive stimulation therapy administered by the caregiver up to three times a week over 25 weeks CG: CAU	Primary* ▪ Cognition: ADAS-Cog (PwD) ▪ Self-reported QoL: QoL-AD (PwD) ▪ QALY (carer) derived from the EQ-5D-3 L Secondary PwD* ▪ Quality of caregiver-patient relationship: QCPR	CSRI	(I) Health & social care perspective (II) Societal perspective	CST did neither improve cognition or QoL of PwDs, nor carers’ physical and mental health. Costs of the intervention were offset by some reductions in social care and other services. Considering the primary outcomes for PwDs, it seems that the intervention is not more cost-effective compared to CAU (from both perspectives).
Woods [26] UK, 2012	RCT CEA CUA	C: 10 months H: 10 months	Community-dwelling PwDs with mild or moderate dementia and a respective caregiver willing to participate ▪ 488 randomized dyads ▪ 350 dyads completed the study	IG: Weekly reminiscence groups attended by both caregiver and patient over a period of 12 weeks followed by monthly maintenance sessions for a further 7 months CG: CAU	Primary (CEA) ▪ QoL-AD (PwD) ▪ GHQ of caregivers Secondary (CUA) ▪ EQ-5D of both caregiver and PwD ▪ EQ-5D proxy rated by the caregivers	CSRI	Public sector, multiagency perspective (NHS and local governments)	Joint reminiscence groups for PwDs and their caregivers are unlikely to be cost-effective. Potential beneficial effects for PwDs are offset by raised anxiety and stress in their caregivers.
D’Amico [21] UK, 2015	RCT CEA CUA	C: 6 months H: 6 months	Persons with mild-to-moderate dementia according to the DSM-IV criteria and a score between 0.5 and 2.0 on the Clinical Dementia Rating ▪ 236 randomized participants ▪ 199 completed the second follow up at 6 months	IG: After all participants completed 7 weeks of standard cognitive stimulation therapy (CST), the intervention group received MCST for 24 weeks in addition to usual care CG: 7 weeks of standard cognitive stimulation therapy (CST) and afterwards CAU	Primary ▪ ADAS-Cog ▪ QoL-AD Secondary ▪ MMSE ▪ ADCS-ADL ▪ NPI ▪ EQ-5D-3 L (PwD self-report or proxy) ▪ QoL-AD (proxy) ▪ DEMQOL	CSRI completed by caregivers or center workers	(I) Health & social care perspective (II) Societal perspective	Maintenance CST appeared cost-effective when looking at self-rated QoL and cognition (MMSE) and proxy-rated QoL as secondary outcomes. CST in combination with AChEIs offered cost-effectiveness gains when outcome was measured as cognition.

ADCS-ADL = Alzheimer’s Disease Cooperative Study-Activities of Daily Living Inventory, AChEI = Acetylcholinesterase inhibitor, ADAS-Cog = Alzheimer’s Disease Assessment Scale-Cognition subscale, CAU = Care as usual, CEA = Cost-effectiveness analysis, CSRI = Client Service Receipt Inventory, CST = Cognitive stimulation therapy, CUA = Cost-utility analysis, DSM-IV = Diagnostic and Statistical Manual of Mental Disorders, 4th Edition, EQ-5D = EuroQoL 5-dimensions, GHQ = General Health Questionnaire, MCST = Maintenance Cognitive Stimulation Therapy, MMSE = Mini-Mental State Examination, PwD = Person with dementia, NHS = National Health Service, NPI = Neuropsychiatric Inventory, QCPR = Quality of Caregiver-Patient Relationship, QoL = Quality of Life, QoL-AD = Quality of Life in Alzheimer’s Disease, RCT = Randomized controlled trial

*Only primary and secondary outcomes with significant between-group differences were presented in the original paper