Table 3. Summary of recruitment strategies across studies.
| Recruitment strategy | Number of studies where strategy was used | Average cost per randomised participant (in GBP) with original data1 | Number of times recruiting the most within study |
|---|---|---|---|
| Web-based adverts2 | 2 | £13.41 | 2 |
| Via specialised care | 4 | £183.24 | 1 |
| Via secondary care | 2 | not reported | 1 |
| Non-web-based adverts | 3 | £372.03 | 1 |
| Financial incentives3 | 1 | not reported | 1 |
| Via primary care | 4 | £407.65 | 2 |
| Others | 4 | not reported | 0 |
Notes
1. The cost results account for the average exchange rates GBP/AUD and GBP/USD in year 2016, and inflation rates ofthe countries of publication from year of publication until 2016. (http://www.ukforex.co.uk/forex-tools/historical-rate-tools/yearly-average-rates; http://ination.stephenmorley.org/; U.S. Internal Revenue Service)
2. Results on web-based adverts included Morgan (2013), a study which used a number of different online resources to recruit patients.
3. Results on financial incentives included DeBar (2009), a study which used different incentives to recruit patients.