Comprehensive Geriatric Assessment: Diagnostic Performance
CGA demonstrates high sensitivity (>85%) and specificity (>80%) for detecting mild cognitive impairment and frailty, significantly outperforming single-domain screening tools like the Montreal Cognitive Assessment alone 1.
Diagnostic Accuracy for Specific Conditions
Mild Cognitive Impairment
When compared head-to-head against the MoCA using Petersen criteria as the gold standard, CGA achieved superior diagnostic sensitivity and specificity (P < 0.05) 1. The multidimensional approach captures cognitive deficits through:
- Mini-Mental State Examination scores
- Functional assessments (Activities of Daily Living, Instrumental Activities of Daily Living)
- Nutritional status (Miniature Nutritional Assessment)
- Physical performance (Berg Balance Scale)
- Frailty screening
Patients with mild cognitive impairment showed significantly lower scores across these domains compared to healthy controls, allowing CGA to identify subclinical deficits that single cognitive tests miss 1.
Frailty and Functional Impairment
The Frailty Index derived from CGA (FI-CGA) is a robust, validated predictor of adverse outcomes including mortality, hospitalization, and functional decline 2. Recent evidence from 2024-2025 confirms that:
- CGA-based frailty assessment quantifies severity with high precision
- Digital adaptations (eFI-CGA) maintain accuracy while improving workflow
- The tool performs consistently across acute, long-term, primary, and community care settings 2, 3
Clinical Outcomes vs. Diagnostic Metrics
While the question asks about sensitivity/specificity, what matters most for patient outcomes is that CGA-guided management (GAM) significantly reduces mortality, hospitalizations, and disability 4, 3. The 2023 ASCO guideline upgrade—based on large RCTs—now mandates GAM for all adults ≥65 years with cancer and GA-identified deficits, demonstrating that CGA's value extends beyond diagnostic accuracy to actionable intervention 4.
Key Performance Characteristics
CGA reliably detects conditions that chronological age alone cannot predict:
- Frailty (prevalence 5-50% depending on age)
- Cognitive impairment
- Motor dysfunction
- Polypharmacy risks
- Fall risk 5, 6
The assessment unmasks subclinical deficits through validated instruments including frailty indices, neuropsychological tests, Timed-Up-and-Go, gait speed, and handgrip strength 5.
Important Caveats
CGA is not a single test but a multidimensional process, so sensitivity/specificity vary by:
- Which specific domains are assessed
- The reference standard used (e.g., Petersen criteria for MCI, clinical frailty scale)
- The population studied (community-dwelling vs. hospitalized)
- Whether manual or electronic CGA is employed 2
The evidence base is strongest for urban, high-income settings; generalizability to rural or low-resource environments requires caution 6. However, the 2024 Mayo Clinic guideline emphasizes that clinical adaptation based on resources is appropriate, recommending the Practical Geriatric Assessment as one streamlined option 7.
Practical Application
For detecting frailty and functional impairment, CGA should include these high-priority domains 4:
- Physical function
- Cognitive function
- Emotional health
- Comorbid conditions
- Polypharmacy
- Nutrition
- Social support
The diagnostic accuracy is highest when all essential domains are assessed, as the interplay between frailty, multimorbidity, and polypharmacy (the "geriatric triangle") requires integrated evaluation 3.