cb Ray 2011.

Methods	See bb Ray 2011. Study data were analysed using a cohort design.
Participants
Interventions
Outcomes
Notes	Government funded
Risk of bias
Bias	Authors' judgement	Support for judgement
PCS/RCS ‐ selection exposed cohort All outcomes	Unclear risk	Unclear
PCS/RCS ‐ selection non‐exposed cohort All outcomes	Unclear risk	Unclear
PCS/RCS ‐ comparability All outcomes	Unclear risk	Unclear
PCS/RCS ‐ assessment of outcome All outcomes	Unclear risk	Unclear
Summary assessment	Unclear risk	Unclear