Miki 1969.

Study characteristics
Methods	Study design: prospective cohort longitudinal Location: Tokyo, Japan Time period: 1961 to 1967 Outcome: PDR Outcome measurement: incidence
Participants	Number of participants: 364 Diabetes type: unclear Inclusion criteria: ambulatory participants followed regularly for more than 2 years   Exclusion criteria: not reported
Notes	Link to data extraction table, risk of bias assessment, and results: osf.io/zqtjp/?view_only=aec8c2150af54750b293894ae53284b4
Item	Authors' judgement	Support for judgement
Study participation	Unclear	See ‘Notes’ above for link to risk of bias assessment
Study attrition	No	See ‘Notes’ above for link to risk of bias assessment
Prognostic factor measurement	Unclear	See ‘Notes’ above for link to risk of bias assessment
Outcome measurement	Unclear	See ‘Notes’ above for link to risk of bias assessment
Adjustment for other prognostic factors	No	See ‘Notes’ above for link to risk of bias assessment
Statistical analysis and reporting	No	See ‘Notes’ above for link to risk of bias assessment