| Name of study |
Mexico City Diabetes Study |
| Inclusion criteria |
Population‐based study of diabetes and cardiovascular risk factors in low‐income neighbourhoods in Mexico City, participants aged 35–64 years |
| Exclusion criteria |
Type 2 diabetes, type 1 diabetes, pregnant women |
| Notes |
Baseline characteristics provided for a range across different definitions of 'prediabetes' |
| Risk of bias |
| Bias |
Authors' judgement |
Support for judgement |
| Study participation: description of source population or population of interest |
Low risk |
Data were collected as part of the Mexico City Diabetes Study |
| 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 |
Low risk |
Description of inclusion and exclusion criteria |
| Study attrition: description of attempts to collect information on participants who dropped out |
Unclear risk |
Not reported |
| Study attrition: reasons for loss to follow‐up provided |
Low risk |
Yes |
| Study attrition: adequate description of participants lost to follow‐up |
Low risk |
Yes |
| Study attrition: no important differences between participants who completed the study and those who did not |
Unclear risk |
Unclear, limited data |
| Glycaemic status measurement: provision of clear definition or description of glycaemic status |
Low risk |
(i)IFG, (i)IGT |
| 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 6.1–6.9; IGT: FPG < 7.0 and 2‐h PG 7.8–11.1; i‐IFG6.1/i‐IFG5.6: 2‐h PG < 7.8 and FPG 6.1–6.9/5.6–6.1; i‐IGT/i‐IGT6.1/i‐IGT5.6
|
| 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 |
Unclear risk |
Not for transition data (intermediate hyperglycaemia to T2DM) |
| Study confounding: clear definitions of important confounders provided |
Low risk |
Yes |
| Study confounding: measurement of confounders valid & reliable |
Low risk |
Yes |
| 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 |
Unclear risk |
Scarce data |
| Study confounding: important potential confounders accounted for in the analysis |
Unclear risk |
Scarce data |
| Statistical analysis & reporting: sufficient presentation of data to assess adequacy of the analytic strategy |
Low risk |
Cumulative incidence, relative risk (multiple model odds ratios were calculated for 1 SD of the population value of that variable, in order to compare the relative importance of the variables (sex, familial diabetes, age, BMI, FPG, 2‐h PG) |
| Statistical analysis & reporting: the statistical model is adequate for the design of the study |
Unclear risk |
Logistic regression (for calculation of odds ratios, see above) |
