Table 2 Development of outcome groupings.
Outcome measure | Forrest et al. (2008) | Kardashian et al. (2012) | Montgomery et al. (2013) | Hodgson et al. (2016) | Eijzenga et al. (2018) |
|---|---|---|---|---|---|
Primary outcome measures | |||||
 Self-report |  | x | x |  | x |
 Relative contacting service | x |  |  | x |  |
 Relative tested | x | x |  |  |  |
Secondary outcome measures | |||||
 Knowledge |  | x |  |  | x |
 Motivation |  |  |  |  | x |
 Self-efficacy |  |  |  |  | x |
 Distress |  |  | x |  |  |
 Gender differences | x | xa | x |  | x |
 Evaluation (feasibility/ acceptability) | x |  |  | x | |