Table 1 Summary of techniques used in the intervention letter
From: Improving postal survey response using behavioural science: a nested randomised control trial
Technique | Example detailed in the intervention letter | Dominant Rationale or Theoretical Framework |
|---|---|---|
University sponsorship as the dominant letterhead | Large University College London (UCL) logo placed at the top of the letter, with National Institute for Health Research (NIHR) logo placed at the bottom right. | |
Salient and attractive letterhead to increase likelihood of attention and relevance | Coloured letterhead used (blue logo) | Salience (MINDSPACE) [22] |
Authoritative messenger to convey importance and obligation | “I am the Co-Director of the Cancer Screening Group” | Messenger (MINDSPACE) [22] |
Emphasising importance to elicit a sense of duty and personal value | “important research study “ “Your involvement is really valuable” | Ego (MINDSPACE) [22] |
Referring to emotion to elicit personal connection | “how your test result has made you feel” | Affect (MINDSPACE) [22] |
Conveying social norms by referencing the majority target group | “most women find…rewarding.” “result letters better for other women” | Norms (MINDSPACE) [22] |
Language to convey personalisation | “I am interested in your particular test result” “I’d like to hear your views” “particularly interested in hearing from you” | |
Perception of exclusivity and possible sanction (i.e., missing out) | “I am only inviting a select number...” | Ego and Incentive (MINDSPACE) [22] |
Salience and visual breaking | Coloured subheadings (“Your role” and “Optional interview”) to break up paragraphs | Salience (MINDSPACE) [22] |
Perceived sanction in bold to elicit loss-aversion | “You have three weeks...to take part” | Incentives (MINDSPACE) [22] |
Minimise short-term costs (e.g., low effort) and emphasise gains | “easy and quick” “enjoyable and rewarding” “You just need to fill in… the short questionnaire” | Incentives (MINDSPACE) [22] |
Assurance of confidentiality of survey answers | “your answers will be kept strictly confidential” | |
Coloured written signature | A signature using bright blue ink at the end of the letter | Systematic review evidence [8] |