Table 4.
Correlations among variables in full simulated memory cognitive score data and differences compared to correlations among variables in available case analyses data, data imputed using multiple imputation and after applying pattern mixture modelling
Memory cognitive function | Smoking status | Age | Grade | Education | ||||||
---|---|---|---|---|---|---|---|---|---|---|
Phase | 5 | 7 | 9 | 5 | 7 | 9 | 5 | 5 | 5 | |
Full simulated data | Mem 5 | 1 | ||||||||
Mem 7 | 0.4419 | 1 | ||||||||
Mem 9 | 0.4423 | 0.4458 | 1 | |||||||
Smoke 5 | −0.0806 | −0.0884 | −0.1041 | 1 | ||||||
Smoke 7 | − 0.0715 | − 0.0800 | − 0.0948 | 0.9616 | 1 | |||||
Smoke 9 | −0.0636 | −0.0764 | − 0.0902 | 0.9337 | 0.9592 | 1 | ||||
Age | −0.2729 | − 0.3127 | − 0.3379 | 0.0281 | 0.0369 | 0.0451 | 1 | |||
Grade | −0.2404 | − 0.1913 | − 0.1660 | 0.0983 | 0.0881 | 0.0817 | −0.0501 | 1 | ||
Education | 0.2058 | 0.1919 | 0.1779 | −0.1114 | − 0.1043 | − 0.1005 | − 0.0784 | − 0.3691 | 1 | |
Differencesa in correlations from those above | ||||||||||
Available case | Mem 5 | 0 | ||||||||
Mem 7 | 0.0355 | 0 | ||||||||
Mem 9 | 0.0544 | 0.0630 | 0 | |||||||
Smoke 5 | 0.0159 | 0.0029 | 0.0040 | 0 | ||||||
Smoke 7 | 0.0071 | 0.0032 | 0.0004 | 0.0009 | 0 | |||||
Smoke 9 | 0.0137 | −0.0005 | 0.0050 | 0.0025 | 0.0087 | 0 | ||||
Age | −0.1632 | − 0.1679 | − 0.2154 | − 0.0253 | − 0.0237 | − 0.0194 | 0 | |||
Grade | −0.0120 | − 0.0102 | − 0.0125 | 0.0066 | 0.0043 | 0.0004 | −0.0104 | 0 | ||
Education | 0.0052 | 0.0032 | 0.0339 | −0.0050 | − 0.0022 | 0.0015 | − 0.0151 | − 0.0031 | 0 | |
Multiple imputation | Mem 5 | 0 | ||||||||
Mem 7 | 0.0157 | 0 | ||||||||
Mem 9 | 0.0970 | 0.0364 | 0 | |||||||
Smoke 5 | 0.0528 | 0.0579 | 0.0306 | 0 | ||||||
Smoke 7 | 0.0522 | 0.0550 | 0.0360 | 0.0062 | 0 | |||||
Smoke 9 | 0.0532 | 0.0506 | 0.0377 | 0.0083 | 0.0080 | 0 | ||||
Age | −0.0186 | −0.0298 | − 0.0269 | − 0.1200 | − 0.1246 | − 0.1237 | 0 | |||
Grade | 0.0067 | − 0.0012 | − 0.0070 | − 0.0116 | − 0.0145 | − 0.0079 | 0 | 0 | ||
Education | − 0.0067 | 0.0169 | 0.0066 | 0.0282 | 0.0272 | 0.0329 | 0 | 0 | 0 | |
Pattern mixture modelling | Mem 5 | 0 | ||||||||
Mem 7 | 0.0115 | 0 | ||||||||
Mem 9 | 0.0877 | 0.0099 | 0 | |||||||
Smoke 5 | 0.0528 | 0.0675 | 0.0410 | 0 | ||||||
Smoke 7 | 0.0522 | 0.0655 | 0.0464 | 0.0062 | 0 | |||||
Smoke 9 | 0.0532 | 0.0612 | 0.0481 | 0.0083 | 0.0080 | 0 | ||||
Age | −0.0186 | − 0.0204 | − 0.0194 | − 0.1200 | − 0.1246 | − 0.1237 | 0 | |||
Grade | 0.0067 | 0.0020 | 0.0007 | −0.0116 | − 0.0145 | − 0.0079 | 0 | 0 | ||
Education | −0.0067 | 0.0123 | −0.0001 | 0.0282 | 0.0272 | 0.0329 | 0 | 0 | 0 |
aDifferences in correlations are calculated as correlation in analysis type minus correlation in full simulated data