Analysis | Number of studies | N in Tx/ control condition | Pooled effect size g (95% CI)*,† | Overall effect: Z (p value) | Heterogeneity: I2% (p Value) | Prediction interval: 95% CI | Publication bias-egger's asymmetry test bias coefficient (p) |
---|---|---|---|---|---|---|---|
CS | |||||||
Postintervention-MMSE* | |||||||
CS vs NA | 17 | 553/457 | 0.51 (0.35 to 0.66) | 6.23 (≤0.001) | 24.9 (0.167) | 0.12 to 0.89 | 1.09 (0.14) |
CS vs Active | 3 | 108/83 | 0.35 (0.06 to 0.64) | 2.34 (0.019) | 0.0 (0.72) | n/a | −2.67 (0.55) |
Post-Intervention-ADAS-Cog† | |||||||
CS vs NA No studies of CS vs Active | 9 | 347/313 | −0.26 (−0.44 to −0.08) | 2.82 (0.005) | 18.5 (0.28) | −0.62 to 0.10 | −0.017 (0.99) |
Postintervention-Other general cog outcome | |||||||
CS vs NA | 2 | 21/14 | 0.25 (−0.44 to 0.94) | 0.71 (0.48) | 0.0 (0.75) | n/a | UC |
Follow-up | |||||||
CS vs NA at 3 months (MMSE) | 2 | 49/40 | 0.80 (0.05 to 1.54) | 2.10 (0.036) | 54.5 (0.14) | n/a | UC |
CS vs NA at 6 months (MMSE) | 3 | 56/58 | 0.27 (−0.10 to 0.64) | 1.45 (0.15) | 0.0% (0.61) | n/a | −1.30 (0.76) |
CS vs NA at 10 months (ADAS-Cog) | 2 | 76/74 | −0.40 (−0.72 to −0.08) | 2.41 (0.016) | 0.0% (0.38) | n/a | UC |
CT | |||||||
Postintervention-MMSE | |||||||
CT vs NA | 1 | 16/16 | n/a | n/a | n/a | n/a | UC |
CT vs Active No studies of CT vs Active or Non-active using ADAS-Cog | 3 | 45/42 | 0.22 (0.75 to 1.18) | 0.44 (0.66) | 76.9 (0.01) | −11.03 to 11.47 | −4.16 (0.61) |
No follow-up studies of CT | |||||||
MCTS | |||||||
Postintervention-MMSE | |||||||
CTCS vs NA | 3 | 41/27 | 0.45 (−0.57 to 1.46) | 0.86 (0.39) | 73.8 (0.02) | −11.33 to 12.23 | −4.66 (0.79) |
CTCS vs active | 3 | 43/41 | 0.25 (−0.18 to 0.69) | 1.15 (0.25) | 0.0 (0.39) | n/a | 3.74 (0.22) |
*For the MMSE outcome, a positive value of g denotes a benefit of the intervention compared with the control.
†For the ADAS-Cog outcome, a negative value of g denotes a benefit of the intervention compared with the control.
ADAS-Cog, Alzheimer's disease Assessment Scale-cognitive subscale; CS, cognitive stimulation; CT, cognitive training; MCTS, mixed cognitive training and cognitive stimulation interventions; MMSE, mini-mental state examination; n/a, not applicable; NA, non-active control group; UC, unable to calculate.