Table 3.
Association between education and prevalence of undiagnosed diabetes, the Tromsø Study 1994–2016
| Undiagnosed diabetes as % of people without known diabetes | Undiagnosed as % of all diabetes | |||||||||
| N* | Primary | Secondary | Tertiary | N | Primary | Secondary | Tertiary | |||
| Prevalence ratio (95% CI) | Prevalence ratio (95% CI) | |||||||||
| Pooled data | P value | P value | ||||||||
| Crude (both sexes) | 26 394 | 1 (reference) | 0.63 (0.54 to 0.75) | 0.34 (0.28 to 0.42) | <0.01 | 2099 | 1 (reference) | 0.87 (0.76 to 1.00) | 0.72 (0.61 to 0.85) | <0.01 |
| Model 1 (both sexes)† | 26 394 | 1 (reference) | 0.71 (0.60 to 0.83) | 0.47 (0.38 to 0.57) | <0.01 | 2099 | 1 (reference) | 0.85 (0.73 to 0.98) | 0.77 (0.64 to 0.91) | <0.01 |
| Model 2 (both sexes)† | 26 359 | 1 (reference) | 0.75 (0.63 to 0.88) | 0.54 (0.44 to 0.66) | <0.01 | 2086 | 1 (reference) | 0.85 (0.73 to 0.98) | 0.78 (0.65 to 0.93) | <0.01 |
| Crude men | 12 487 | 1 (reference) | 0.68 (0.55 to 0.85) | 0.43 (0.34 to 0.55) | <0.01 | 1144 | 1 (reference) | 0.83 (0.69 to 0.99) | 0.72 (0.59 to 0.88) | <0.01 |
| Model 1 men‡ | 12 487 | 1 (reference) | 0.76 (0.61 to 0.94) | 0.56 (0.43 to 0.73) | <0.01 | 1144 | 1 (reference) | 0.83 (0.69 to 1.00) | 0.78 (0.64 to 0.97) | 0.02 |
| Model 2 men‡ | 12 473 | 1 (reference) | 0.78 (0.63 to 0.98) | 0.62 (0.48 to 0.80) | <0.01 | 1136 | 1 (reference) | 0.83 (0.69 to 1.00) | 0.79 (0.64 to 0.98) | 0.02 |
| Crude women | 13 907 | 1 (reference) | 0.54 (0.42 to 0.70) | 0.23 (0.17 to 0.31) | <0.01 | 955 | 1 (reference) | 0.88 (0.71 to 1.09) | 0.65 (0.49 to 0.87) | <0.01 |
| Model 1 women‡ | 13 907 | 1 (reference) | 0.64 (0.49 to 0.83) | 0.34 (0.24 to 0.48) | <0.01 | 955 | 1 (reference) | 0.85 (0.68 to 1.06) | 0.72 (0.53 to 0.97) | 0.02 |
| Model 2 women‡ | 13 886 | 1 (reference) | 0.69 (0.53 to 0.89) | 0.41 (0.29 to 0.58) | <0.01 | 950 | 1 (reference) | 0.85 (0.68 to 1.06) | 0.72 (0.53 to 0.98) | 0.02 |
Education categories, primary (primary and lower secondary education), secondary (high school or vocational school) and tertiary education (college and university level).
*Numbers vary slightly due to missing data for some covariates (see table 1); missing body mass index: 164 (0.6%).
†Model 1: adjustment for age, sex and period of survey. Model 2: adjustment for age, sex, body mass index and period of survey.
‡Model 1: adjustment for age and period of survey. Model 2: adjustment for age, body mass index and period of survey.