Comparison 2. Exenatide vs no treatment (14 months (60.8 weeks) post baseline).

Outcome or subgroup title	No. of studies	No. of participants	Statistical method	Effect size
2.1 PD motor impairment ‐ MDS‐UPDRS Part III (off medication)	1		Mean Difference (IV, Fixed, 95% CI)	Subtotals only
2.2 HRQoL ‐ PDQ‐39 SI	1		Mean Difference (IV, Fixed, 95% CI)	Subtotals only
2.3 Serious adverse events	1		Risk Ratio (M‐H, Fixed, 95% CI)	Subtotals only
2.4 Adverse events ‐ weight loss (kg) (assessed at 12 months (52 weeks))	1		Mean Difference (IV, Fixed, 95% CI)	Subtotals only
2.5 PD motor impairment ‐ MDS‐UPDRS Part III	1		Mean Difference (IV, Fixed, 95% CI)	Subtotals only
2.6 PD motor impairment ‐ Rush Dyskinesia Rating Scale	1		Mean Difference (IV, Fixed, 95% CI)	Subtotals only
2.7 Non‐motor impairment ‐ MDS‐UPDRS Part I	1		Mean Difference (IV, Fixed, 95% CI)	Subtotals only
2.8 Activities of daily living ‐ MDS‐UPDRS Part II	1		Mean Difference (IV, Fixed, 95% CI)	Subtotals only
2.9 Psychological outcomes ‐ Mattis DRS	1		Mean Difference (IV, Fixed, 95% CI)	Subtotals only
2.10 Psychological outcomes ‐ MADRS	1		Mean Difference (IV, Fixed, 95% CI)	Subtotals only