Study designs of evaluations included in the review
Only double-blind randomised controlled trials (RCTs) were eligible for the review. The included trials were of 6 to 12 weeks' duration.
Specific interventions included in the review
Studies of clozapine, risperidone, olanzapine, quetiapine, amisulpride, zotepine, sertindole, aripiprazole and ziprasidone were eligible for the review. The included studies compared risperidone and olanzapine with placebo or haloperidol. One study of intramuscular olanzapine was excluded. Fixed doses of 0.5, 1 or 2 mg of risperidone, or flexible dosing with a mean dose of 0.85 to 1.1 mg, were used. Olanzapine was used at a fixed dose of 5, 10 or 15 mg.
Participants included in the review
Studies of patients suffering from dementia were eligible. Most of the included studies were of patients living in institutions, most were elderly (mean age 82 years), and most had severe dementia (mean score on mini-mental state examination was 6.8 out of 30).
Outcomes assessed in the review
The inclusion criteria were not specified in terms of outcomes. The review assessed efficacy, safety and withdrawals. The included studies used a range of assessment tools to measure efficacy: the behavioural pathology in Alzheimer's disease rating scale (BEHAVE-AD), the Cohen-Mansfield agitation inventory (CMAI), the neuropsychiatric rating scale home version (NPI-NH), the brief psychiatric rating scale and the clinical global impressions scale. The included trials measured 'clinical response' in different ways.
How were decisions on the relevance of primary studies made?
Two specialists in geriatric medicine selected studies for inclusion in the review.