Proctor 1998.

Methods	Cluster‐randomised trial, UK
Participants	98 care staff in residential nursing homes
Interventions	1) Experimental: Developing knowledge and skills and individual programme planning: 7 hour‐long seminars over a period of 6 months about the theoretical basis of organic and functional disorders experienced in old age and approaches to care and activities in residential settings. The second part of the training schedule consisted of weekly visits to intervention homes by an experienced psychiatric nurse who trained staff in behavioural management of residents by developing individual care programmes for them. 2) Control: No intervention
Outcomes	The Occupational Stress Indicator, GHQ
Notes	Measurements were completed at baseline and immediately following the 6‐month intervention. We accounted for the design effect (participants randomised in clusters but analysed as individuals) by dividing the number of participants by the calculated design effect of 1.143.
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	"Ten residential care homes and two nursing homes participated in the study and were matched into pairs according to size and accreditation status. One of each pair of homes was then randomised to one of two groups by computer." (p. 3)
Allocation concealment (selection bias)	Unclear risk	Not reported
Blinding (performance bias and detection bias) All outcomes	High risk	Not possible, self report
Incomplete outcome data (attrition bias) All outcomes	Low risk	"There was no survivor effect due to staff attrition on any of the measures completed; missing data were replaced by the last known assessment carried forward." (p. 5)
Selective reporting (reporting bias)	Low risk	All outcomes reported
Other bias	Unclear risk	We did not find any indications of other sources of bias