Table 1 Themes and categories based on the Diffusion of Innovations model [25] reported by participants

Personal experiences of stress and morale

• 4HR/NEAT improved the clinical role performance (8; 11)

• 4HR/NEAT improved morale in ED staff (18; 52)

• 4HR/NEAT decreased stress (4; 4)

• 4HR/NEAT increased workload (81; 419)

• 4HR/NEAT increased stress and decreased morale (109; 1147)

Intergroup dynamics

• 4HR/NEAT improved relationships with rest of the hospital (33; 40)

• 4HR/NEAT signified the importance of hospital’s executive buy-in (21; 59)

• 4HR/NEAT necessitated the Whole of Hospital Approach (WoHA) (87; 334)

• 4HR/NEAT improved communications within ED staff (29; 50)

• 4HR/NEAT improved ED teams and teamwork (25; 39)

• 4HR/NEAT increased autonomy of ED staff (16; 25)

• 4HR/NEAT undermined ED teams and teamwork (35; 82)

• 4HR/NEAT worsened communication within ED staff (26; 43)

• 4HR/NEAT shifted the power in decision making from ED to hospital executives (6; 7)

• 4HR/NEAT impaired relationships with rest of the hospital (77; 257)

• Hospital failed to employ the WoHA (54; 190)

• Suboptimal leadership and insufficient buy-in at hospital executive confounded 4HR/NEAT-related changes (47; 128)

Interaction with patients

• 4HR/NEAT improved staff-patient communication (26; 56)

• 4HR/NEAT had no change on staff-patient relationships (17; 20)

• 4HR/NEAT decreased staff-patient communication (43; 140)

• Non-4HR/NEAT factors influencing staff-patient communication (6; 6)