second study investigated whether the playing of the patients’ preferred music can reduce agitation in comparison with the play- ing of classical music. The investigators tested the hypothesis that music must have specific meaning for each individual to be ef- fective, rather than that music of any kind is effective (Gerdner 2000). In this study, 39 older people with dementia were ran- domly assigned either to a preferred music condition or to a mu- sic condition in which the residents listened to standard classical relaxation music, both treatments were offered for a period of six weeks. The randomisation was stratified by age, sex, and severity of dementia.