Table 5: Mixed effects model summaries across four studies with baseline cognitive activity and activity change predicting four cognitive outcomes.

Octo-TwinLBLSSLSVLS
ReasoningCommunicationComputationConundrums
𝑏 SE 𝑃 bSE 𝑃 bSE 𝑃 bSE 𝑃 bSE 𝑃 bSE 𝑃

Intercept11.170.64<0.00120.980.58<0.00114.830.18<0.0019.600.58<0.0019.060.56<0.0019.640.57<0.001
Age−0.320.100.002−0.600.05<0.001−0.350.01<0.001−0.250.02<0.001−0.220.02<0.001−0.240.02<0.001
Sex0.100.590.8622.580.820.0021.400.24<0.001−0.120.310.7000.420.310.170−0.19−0.190.300
Education0.390.140.0151.240.15<0.0010.480.05<0.0010.290.05<0.0010.250.05<0.0010.320.05<0.001
Activity1.460.18<0.0010.020.330.9560.340.110.0010.450.200.0241.240.19<0.0010.940.19<0.001
Age × activity0.050.060.3890.090.040.0200.010.010.2860.000.020.8760.040.020.0780.020.020.447
Education × activity−0.050.060.4530.040.100.702−0.050.030.168−0.120.050.0200.000.050.9230.050.050.404
Time−0.450.09<0.001−0.500.08<0.001−0.250.02<0.001−0.240.03<0.001−0.250.03<0.001−0.250.03<0.001
Age × time−0.020.020.274−0.030.010.000−0.010.00<0.001−0.010.00<0.001−0.010.00<0.001−0.010.00<0.001
Sex × time0.090.100.3670.070.110.5360.010.020.5450.020.030.5980.040.030.2320.010.030.643
Education × time0.030.020.224−0.060.020.008−0.010.000.092−0.010.010.091−0.010.000.061−0.010.000.138
Activity × time0.020.030.5950.050.050.3370.010.010.1730.030.020.1450.050.020.025−0.010.020.692
Activity change0.410.130.0020.280.200.1640.240.090.0060.380.140.0050.490.13<0.0010.230.120.059

LBLSSLSVLS
FluencyCommunicationComputationConundrums
bSE 𝑃 bSE 𝑃 bSE 𝑃 bSE 𝑃 bSE 𝑃

Intercept30.940.66<0.00136.460.46<0.00111.680.53<0.00111.280.55<0.00111.730.53<0.001
Age−0.310.05<0.001−0.340.04<0.001−0.080.020.001−0.080.020.002−0.070.020.006
Sex3.420.93<0.0012.880.61<0.0010.630.340.0651.020.360.0050.540.340.115
Education0.880.17<0.0011.170.11<0.0010.470.05<0.0010.580.05<0.0010.600.05<0.001
Activity1.140.370.0021.030.270.0011.800.22<0.0010.810.22<0.0011.680.21<0.001
Age × activity0.070.040.1210.000.030.9000.010.030.7090.040.030.1120.040.030.094
Education × activity0.050.110.6510.000.080.995−0.120.060.042−0.040.050.4890.030.060.659
Time−0.220.110.052−0.420.04<0.001−0.110.03<0.001−0.130.03<0.001−0.130.03<0.001
Age × time−0.020.010.015−0.020.00<0.001−0.010.000.001−0.010.000.001−0.010.000.001
Sex × time−0.170.150.2520.110.050.0250.070.040.0580.080.040.0500.070.040.078
Education × time0.010.030.778−0.010.010.1050.000.010.8230.000.010.9550.000.010.954
Activity × time−0.060.070.3500.020.020.3240.000.030.8680.020.030.4480.010.030.793
Activity change0.490.300.0970.500.200.0120.760.18<0.0010.680.18<0.0010.480.160.003

Octo-TwinLBLSSLSVLS
MemoryCommunicationComputationConundrums
𝑏 SE 𝑃 bSE 𝑃 bSE 𝑃 bSE 𝑃 bSE 𝑃 bSE 𝑃

Intercept8.840.29<0.00110.730.21<0.00111.680.13<0.00117.370.41<0.00117.060.40<0.00117.510.41<0.001
Age−0.180.060.001−0.200.02<0.001−0.180.01<0.001−0.190.02<0.001−0.170.02<0.001−0.180.02<0.001
Sex0.910.990.0061.410.30<0.0011.400.18<0.0011.580.26<0.0012.130.27<0.0011.500.26<0.001
Education0.350.07<0.0010.250.05<0.0010.260.03<0.0010.230.04<0.0010.250.04<0.0010.300.04<0.001
Activity0.590.10<0.0010.170.120.1420.410.08<0.0010.960.17<0.0011.170.16<0.0010.850.16<0.001
Age × activity−0.010.040.9300.000.010.7760.000.010.9010.070.02<0.0010.060.020.0020.060.020.002
Education × activity−0.020.040.6630.040.040.2470.000.020.948−0.070.040.127−0.020.040.658−0.040.050.345
Time−0.270.07<0.001−0.170.050.001−0.170.01<0.001−0.260.03<0.001−0.260.03<0.001−0.280.03<0.001
Age × time0.000.020.9470.000.000.627−0.010.00<0.001−0.010.00<0.001−0.010.00<0.001−0.010.00<0.001
Sex × time0.060.080.465−0.030.070.7050.030.020.112−0.010.030.783−0.010.030.736−0.010.030.660
Education × time0.000.020.9320.010.010.6910.000.000.5490.000.010.3490.000.000.349−0.010.000.246
Activity × time0.030.020.2310.040.030.2160.000.010.8270.010.020.7080.000.020.9230.030.020.164
Activity change0.350.09<0.0010.250.120.0390.250.070.0010.710.13<0.0010.780.12<0.0010.180.120.126

Semantic knowledgeOcto-TwinLBLSSLSVLS
CommunicationComputationConundrums
𝑏 SE 𝑃 bSE 𝑃 bSE 𝑃 bSE 𝑃 bSE 𝑃 bSE 𝑃

Intercept31.600.69<0.00137.890.59<0.00124.540.23<0.00144.230.68<0.00143.660.68<0.00144.070.69<0.001
Age−0.400.140.004−0.290.05<0.0010.010.020.5010.090.030.0040.110.03<0.0010.090.030.004
Sex−5.170.85<0.0011.600.840.0560.120.310.688−0.070.440.8650.680.460.137−0.180.450.687
Education1.600.20<0.0010.950.15<0.0010.990.06<0.0010.580.07<0.0010.650.07<0.0010.720.07<0.001
Activity2.210.25<0.0010.750.340.0260.810.14<0.0011.970.28<0.0011.770.28<0.0011.370.27<0.001
Age × activity0.030.090.7370.050.040.1990.020.020.2770.050.030.1130.060.030.0740.070.030.039
Education × activity−0.230.100.014−0.050.100.647−0.050.040.206−0.330.07<0.001−0.280.07<0.001−0.090.080.242
Time−0.920.12<0.001−0.400.09<0.001−0.110.01<0.0010.03<0.001−0.140.03<0.001−0.160.03<0.001
Age × time−0.050.030.064−0.030.01<0.001−0.010.00<0.001−0.010.00<0.001−0.010.00<0.001−0.010.00<0.001
Sex × time0.300.140.0360.050.120.6780.060.020.0010.030.040.3790.020.040.5330.030.040.439
Education × time0.040.030.155−0.030.020.1850.000.000.4470.000.010.5100.000.010.7250.000.010.453
Activity × time−0.020.040.5710.030.050.6270.010.010.0690.020.020.442−0.010.020.7730.010.020.524
Activity change0.470.170.0050.440.200.0270.260.07<0.0010.490.150.0010.530.14<0.0010.490.13<0.001

Values represent model coefficients and their standard error. Across all studies, time was measured in years since baseline visit, and activity change was entered as a time-varying covariate. All other variables represent baseline measurements alone, in interaction with one another or in interaction with time.