Table 2.
Association between intellectual enrichment with cognitive function
| Model | DF | AIC | Chisq | P-value |
|---|---|---|---|---|
| Intellectual enrichment | ||||
| Null model | 20 | 3151.6 | ||
| Intellectual enrichment | 21 | 3112.3 | 41.3 | <0.001 |
| Intellectual enrichment by visit | 22 | 3113.7 | 0.6 | 0.452 |
| Intellectual enrichment by DBS | 23 | 3111.9 | 3.8 | 0.050 |
| Intellectual enrichment by DBS by visit | 24 | 3101.4 | 12.5 | <0.001 |
| Intellectual enrichment correcting for education versus education alone | ||||
| Null model | 20 | 3151.6 | ||
| Education by visit by DBS | 24 | 3133.0 | 26.5 | <0.001 |
| Intellectual enrichment by visit by DBS | 28 | 3105.3 | 35.7 | <0.001 |
| Intellectual enrichment correcting for education versus intellectual enrichment alone | ||||
| Null model | 20 | 3151.6 | ||
| Intellectual enrichment by visit by DBS | 24 | 3101.4 | 58.2 | <0.001 |
| Education by visit by DBS | 28 | 3105.3 | 4.1 | 0.397 |
The null model for intellectual enrichment included age at baseline, site (three dummy variables) and DBS at baseline with their interaction with visit and main effects of sex and use of antipsychotic medication. A quadratic term was also included for visit, as well as its interaction with DBS.