Table 1.

Reasons for undertaking the study.

Reason for undertaking the study	n	Reference number
Measuring AE rates	11	[10, 17, 21–29]
Characterising AEs	7	[10, 21, 23, 25–27, 29]
Comparing the GTT with other AE data sources	7	[17, 22, 24, 26, 30–32]
Developing GTT specialty versions	4	[21, 27–29]
Assessing GTT utility	3	[22, 24, 25]