Table 5 Process evaluation framework for analysis

Fidelity

(The degree to which the intervention was delivered as intended)

• What is the intervention?

• Was the intervention (safety plan and follow-up telephone calls) delivered as intended?

• Was there consistency in terms of how the intervention was delivered?

• What, if any, adaptations were needed to the planned intervention? And were they needed?

• What barriers, if any, were there to delivering the intervention in a consistent way? (Safety plan and follow-up telephone calls)

Exposure

(The extent to which participants received and understood the different elements of the intervention and whether they implemented these as intended. Their satisfaction with the intervention and barriers to receipt and implementation was also considered)

• To what extent did participants take up all potential elements of the full programme of intervention (safety plan and 5 follow-up telephone calls)?

• To what degree did participants receive the minimum dose (safety plan and 1 follow-up phone call)?

• To what extent was the safety plan completed as intended by the participant? If it was not, what were the reasons for that?

• How did participants use the safety plan they had developed? (E.g. frequency of use, practicality — where did they keep it, did they share with others)

• To what extent did participants alter or amend their safety plans throughout the course of the intervention?

• What elements of the intervention did participants find helpful/unhelpful and why? What elements of the intervention would participants change and why?

• What changes, if any, did participants feel that they implemented as a result of taking part in the intervention?

• What factors were involved in ongoing engagement with the intervention?

• What do participants report were barriers and facilitators to developing the safety plan, engaging with telephone support, and using the safety plan in practice?

• What feedback do participants have regarding feasibility and acceptability of the safety plan and follow-up telephone calls?

Reach

(The extent to which the target audience is reached by the intervention, as well as any ‘spillover’ effects on people not recruited)

• How well does the study sample represent the population of interest?

• Did participants report sharing their SP with family or friends?

• To what extent did the intervention reach and influence people other than recruited participants?

Context

(Includes information relating to aspects of the context in which the intervention was delivered, as well as broader context that both practitioner and client were operating within that may influence intervention effectiveness)

• What participant-centred contextual factors influenced engagement with the intervention (safety planning and follow-up calls) and use of the safety plan in practice?

• What contextual factors within participants’ day-to-day environment influenced engagement with the intervention (safety planning and follow-up calls) and use of the safety plan in practice?

• How did the context in which the intervention was delivered influence engagement with the intervention and use of the safety plan in practice?

• Was the safety plan useful in certain circumstances and not in others?

• How does the intervention fit in with what is delivered in hospital (how easy was is it to deliver in this setting and does it conflict with anything)?

• What were the particular context-related difficulties/issues that arose during the study in delivering the intervention?

Recruitment and retention

• How did participants feel about being approached/recruited in hospital setting?

• How acceptable were study and intervention procedures to participants?

• What motivated study participants to agree to take part? (And what kept them engaged?)

• Were there any difficulties in recruitment?

• What is the attrition rate overall and by subgroup? I.e. intervention groups and control

• What were the reasons for withdrawal?

Contamination

• What are the characteristics of other groups or services people are attending or resources they are using — do these provide any elements of the intervention?

• Have participants used a safety plan or similar in the past?

• Did participants in the TAU (treatment as usual) arm investigate ‘safety plan’ strategy on their own?

• Have any of the TAU arm participants seen intervention content from other participants?

• How did randomisation to the TAU arm affect participants?