| Name of study |
None |
| Inclusion criteria |
People older 20 years living in the rural area of Dalseong County near Daegu visiting community health centres |
| Exclusion criteria |
Not reported |
| Notes |
1287 participants were re‐evaluated in 2008 and 187 new participants "added to the study"; baseline data for participants with incident diabetes (N = 135) |
| Risk of bias |
| Bias |
Authors' judgement |
Support for judgement |
| Study participation: description of source population or population of interest |
Low risk |
Population‐based survey to determine the prevalence and incidence of 'prediabetes' and diabetes |
| Study participation: description of glycaemic status at baseline |
Low risk |
Yes |
| Study participation: adequate description of sampling frame & recruitment |
Low risk |
Yes |
| Study participation: adequate description of period & recruitment place |
Low risk |
Yes |
| Study participation: adequate description of inclusion & exclusion criteria |
Unclear risk |
Only inclusion criteria described |
| Study attrition: description of attempts to collect information on participants who dropped out |
High risk |
Several surveys plus new recruitment; follow‐up rate 80.5%; no description of dropouts |
| Study attrition: reasons for loss to follow‐up provided |
High risk |
Not reported |
| Study attrition: adequate description of participants lost to follow‐up |
High risk |
Not reported |
| Study attrition: no important differences between participants who completed the study and those who did not |
Unclear risk |
Not reported |
| Glycaemic status measurement: provision of clear definition or description of glycaemic status |
Low risk |
Yes |
| Glycaemic status measurement: valid and reliable method of glycaemic status measurement |
Low risk |
Yes |
| Glycaemic status measurement: continuous variables reported or appropriate cut points used |
Low risk |
IFG: FPG ≥ 5.6 to < 7.0; IGT: 2‐h PG ≥ 7.8 to < 11.1; 'prediabetes': IFG or IGT |
| Glycaemic status measurement: same method and setting of measurement of the glycaemic status for all study participants |
Low risk |
Yes |
| Outcome measurement: clear definition of the outcome provided |
Low risk |
FPG ≥ 7.0; 2‐h PG ≥ 11.1 |
| Outcome measurement: method of outcome measurement used valid & reliable |
Low risk |
Yes |
| Outcome measurement: same method & setting of outcome measurement for all study participants |
Low risk |
Yes |
| Study confounding: important confounders measured |
Low risk |
Several covariates were measured (see Appendix 16 and Appendix 17) |
| Study confounding: clear definitions of important confounders provided |
Unclear risk |
Not reported |
| Study confounding: measurement of confounders valid & reliable |
Unclear risk |
Not reported |
| Study confounding: same method & setting for measurements of confounders for all study participants |
Low risk |
Yes |
| Study confounding: appropriate methods used if missing confounder data imputed |
Unclear risk |
Not reported |
| Study confounding: important potential confounders accounted for in study design |
Low risk |
Yes |
| Study confounding: important potential confounders accounted for in the analysis |
Low risk |
Yes |
| Statistical analysis & reporting: sufficient presentation of data to assess adequacy of the analytic strategy |
Unclear risk |
Odds ratio |
| Statistical analysis & reporting: the statistical model is adequate for the design of the study |
Low risk |
Logistic regression models |
