Table 3. Prevalence of mild cognitive impairment: subtypes, and as based on Clinical Dementia Ratings and Mini-Mental State Examination scores.
| aMCI | naMCI | MMSE | CDR | |||||
|---|---|---|---|---|---|---|---|---|
| Study | Crude | Standardized | Crude | Standardized | Crude | Standardized | Crude | Standardized |
| CFAS | NA | NA | NA | NA | 11.3 (9.1–13.9) | 13.9 (11.7–16.1) | NA | NA |
| EAS | 1.8 (1.3–2.6) | 1.4 (0.9–1.9) | 2.6 (1.9–3.4) | 2.0 (1.4–2.6) | 10.3 (8.9–11.9) | 6.7 (5.7–7.7) | 6.6 (5.4–8.0) | 5.2 (4.1–6.2) |
| ESPRIT | 1.2 (0.8–1.7) | 1.3 (0.7–1.8) | 3.5 (2.8–4.4) | 3.7 (2.8–4.5) | 9.2 (8.1–10.6) | 9.4 (8.0–10.7) | NA | NA |
| HK-MAPS | 1.0 (0.4–2.6) | 0.5 (0.0–0.9) | 4.4 (2.9–6.9) | 5.2 (2.7–7.6) | 14.4 (11.8–17.3) | 14.5 (11.7–17.3) | 13.6 (11.3–16.2) | 14.9 (12.1–17.8) |
| Invece.Ab | 3.9 (3.0–5.2) | 3.0 (2.3–3.7) | 4.4 (3.3–5.8) | 4.0 (3.1–4.9) | 10.7 (9.0–12.7) | 9.9 (8.5–11.2) | NA | NA |
| MoVIES | 2.6 (1.9–3.6) | 2.6 (1.7–3.5) | 4.7 (3.6–6.0) | 5.1 (3.8–6.4) | 18.5 (16.4–20.8) | 19.1 (16.8–21.4) | 1.5 (1.0–2.3) | 1.8 (1.0–2.6) |
| PATH | 1.0 (0.6–1.6) | 1.0 (0.6–1.5) | 2.3 (1.6–3.1) | 2.4 (1.7–3.0) | 1.3 (0.9–2.0) | 2.1 (1.5–2.7) | NA | NA |
| SLAS | 2.0 (1.4–2.9) | 2.2 (1.3–3.1) | 3.2 (2.4–4.2) | 2.8 (1.7–3.9) | 6.5 (5.5–7.6) | 6.7 (5.5–8.0) | 13.6 (11.3–16.3) | 13.9 (10.5–17.3) |
| Sydney MAS | 4.0 (2.9–5.5) | 3.6 (2.5–4.7) | 6.7 (5.3–8.6) | 6.2 (4.7–7.6) | 16.7 (14.4–19.3) | 17.4 (15.1–19.6) | 9.2 (7.4–11.3) | 9.6 (7.8–11.3) |
| WHICAP | 1.6 (1.3–2.1) | 1.5 (1.1–1.9) | 4.8 (4.0–5.6) | 4.6 (3.8–5.4) | NA | NA | 9.5 (8.6–10.5) | 9.3 (8.3–10.2) |
| ZARADEMP | NA | NA | NA | NA | 19.7 (18.4–21.1) | 20.7 (19.2–22.1) | NA | NA |
| Total | 2.0 (1.7–2.2) | 2.0 (1.7–2.2) | 3.9 (3.6–4.2) | 3.9 (3.6–4.2) | 12.0 (11.5–12.5) | 12.0 (11.5–12.4) | 8.5 (8.0–9.2) | 9.0 (8.4–9.6) |
aMCI = amnestic mild cognitive impairment; naMCI = non-amnestic mild cognitive impairment; CDR = Clinical Dementia Rating; MMSE = Mini-Mental State Examination; NA = not applicable. Values are percentage prevalence (95% confidence interval). The objective cognitive impairment criteria for these classifications was for aMCI: performance in the bottom 6.681% of the relevant study for the memory domain; naMCI: performance in the bottom 6.681% of the relevant study for at least one harmonized cognitive domain other than and excluding memory; CDR: a rating of 0.5; MMSE: a score of 24–27. Standardized prevalence estimates were directly standardized for age group and sex, with the standard population being the total sample of all studies included in the analysis; data were imputed for the missing age ranges within Invece.Ab, PATH and Sydney MAS.