Table 1 Inclusion and exclusion criteria

Inclusion criteria for residential settings:

Exclusion criteria for residential settings:

 Provides services via English/Welsh publically funded contracts (Local Authorities, Clinical Commissioning Groups)

 ‘Inpatient’ hospital facility (typically NHS or independent providers)

 Provides support to between one and 10 people with intellectual disability (ID)

 The manager does not receive approval from the service provider organisation for the residential settings to be a part of the study

 Provide at least some 24-h support for people with ID

 Is in a community location

 Provides care for at least one person with ID who engages in aggressive challenging behaviour

 Manager (or equivalent lead staff member) and one other support staff member can be released to attend a ‘Who’s Challenging Who?’ training session together

Inclusion criteria for staff:

Exclusion criteria for staff:

 One staff member will be the manager or other lead staff member (as defined by the service provider organisation)

 Staff do not provide their consent to take part in the research

 The second staff member will be a direct support worker whose role is no more than 50% in administrative/staff management tasks

 Inadequate English reading skills prevent completion of the questionnaire measures

 Both staff work at least a 0.70 full time equivalent or more