Lestradet 1981.

Study characteristics
Methods	Study design: prospective cohort Location: France Time period: 1949 to 1976 Outcome: PDR Outcome measurement: incidence
Participants	Number of participants: 372 Diabetes type: T1D Inclusion criteria: all IDD children (age at onset less than 16 years), whose diabetes was diagnosed between October 1949 and December 1960; followed from the onset of their disease until December 1976 by the Department of Diabetology at the Harold Hospital in Paris   Exclusion criteria: patients previously diagnosed outside the department
Notes	Link to data extraction table, risk of bias assessment, and results: osf.io/rcdpf/?view_only=ac0ce7cab53b43a8b1d17be32afaf799
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	Unclear	See ‘Notes’ above for link to risk of bias assessment