Table 1 Inclusion criteria based on the PICOTS framework modified for prognostic factor and model studies

Population

(i) Adults (aged ≥ 50 years) without cognitive impairment at baseline

(ii) Adults (aged ≥ 50 years) with MCI at baseline

(iii) High-risk individuals aged ≥ 18 years. Here, “high risk” for developing dementia is defined as individuals with ≥ 1 unmodifiable risk factor, such as genetic variants (e.g., APOE4 copy numbers) or chromosomal abnormalities (e.g., Down syndrome)

Index prognostic factor (KQ1)

Blood GFAP levels sampled and assessed at baseline

Comparator prognostic factors (KQ1)

Age, sex, APOE4, Aβ, and other biomarkers including p-tau

Index and comparator RAMs (KQ2)

Any RAMs incorporating blood GFAP levels and other prognostic factors

Outcomes

Clinical conversion of cognitive impairment as the binary outcomes

(i) From no cognitive impairment to MCI or AD

(ii) From MCI to AD

Timing

At least 1 year from baseline

Setting

Blood sampling (for GFAP level measurement) performed in both primary and secondary care