Ridder 2013.

Methods	RCT, cross‐over with 2 periods of 6 weeks for the different conditions Quote: "Data were collected in three 15‐week periods during fall 2010, spring 2011 and fall [autumn] 2011."
Participants	Countries: Denmark and Norway 42 people participated from 14 nursing homes (4 in Denmark and 10 in Norway); most were from Norway (76% of participants) 69% women and mean age was 81 years (range 66–96 years) for the 26% of participants for whom this information was available. The participants had a diagnosis of dementia ("stated in medical journal," no criteria mentioned); 40% had AD; for 38% the type was not specified; 22% had other types of dementia such as vascular, Lewy body, frontotemporal or mixed dementia. Eligible people had moderate‐to‐severe dementia. Mean baseline MMSE score: experimental group: 9.84 (SD 5.97); control group: 5.25 (SD 4.83). Global Deterioration Scale means: experimental group: 5.54 (SD 0.69); control group: 5.80 (SD 0.62). Included participants had symptoms of agitation.
Interventions	Experimental group: individual mixed active‐receptive music therapy, a minimum of 12 sessions were offered, but the participants received a mean of 10 sessions (SD 2.82, range 0 to 13). Frequency: twice a week (over 6 weeks). Mean duration: 33.80 (SD 9.91) minutes Control group: received usual care which for some participants meant participating in group sing‐along sessions
Outcomes	Primary outcome: agitation measured with the CMAI. Timeframe adapted from 2, to 1 week (previous week). In addition to the 7‐point frequency scale, a later version of CMAI was used with a 5‐point disruptiveness scale. The frequency scale, CMAI‐fr, ranged from 1 (never) to 7 (several times per hour), and the disruptiveness scale, CMAI‐di, from 1 (not at all) to 5 (extremely). The CMAI‐fr 1‐ to 7‐point scale was transformed to scores 0 to 6, leading to a maximum total score of 66 and the 1‐ to 5‐point CMAI‐di scale was transformed to scores 0 to 4, leading to a maximum total score of 44. Secondary outcome: quality of life measured with the ADRQL. Timeframe adapted from 2, to 1 week (previous week).
Notes	Psychotropic medication use was measured and considered as an outcome Funding: GC Rieber Foundation in Bergen and Aalborg University
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	Participants were randomly allocated to 1 of 2 groups (experimental or control first) but it was not described how.
Allocation concealment (selection bias)	Low risk	Quote: "[A] concealed sequence procedure" was used, witnessed and signed by someone who was not involved in the study.
Blinding of participants and personnel (performance bias) All outcomes	High risk	Not possible to blind the convener and participants
Blinding of outcome assessment (detection bias) All outcomes	High risk	Interviewers and proxy respondents were not blinded to the treatment allocation.
Incomplete outcome data (attrition bias) All outcomes	Low risk	Only a few values were missing; and sensitivity analyses were performed with last observation carried forward.
Selective reporting (reporting bias)	Unclear risk	Quote: "The researchers designed the study protocol in collaboration with a group of clinicians from Denmark and Norway," but there is no reference to compare with.
Other bias	Unclear risk	Funding source might have an interest in the study outcomes.