Measuring low-value care according to two lenses ((A) patient and (B) service) and three measures using a case example from Scott et al 14
| Lens | Patient | Service | |
| Measure | Patient-indication | Patient-population | Service |
| Numerator of measure | Patients with the low-value indication and the service | ||
| For example, 8955 US Medicare beneficiaries with syncope* that underwent carotid ultrasound | |||
| Denominator of measure | Based on patients with specific indication | Based on all patients (or people) in the cohort | Based on specific services |
| For example, 55 140 beneficiaries with syncope* | For example, 1 340 908 beneficiaries | For example, 137 424 beneficiaries underwent a carotid ultrasound | |
| Findings | Percentage with a specific indication receiving low-value service | Percentage of total receiving a low-value service | Percentage of services that are low-value services |
| For example, 16.2% of beneficiaries with syncope* had a carotid ultrasound | For example, 0.7% of beneficiaries had a carotid ultrasound and syncope* | For example, 6.5% of beneficiaries who received a carotid ultrasound presented with syncope* | |
| Main audience | Clinicians: gives information on the proportion of patients with specific indication or population receiving low-value care | ||
| Policy makers/resource allocation: proportion of services used that are low-value | |||
*Syncope was defined as a syncopal episode not accompanied by focal neurological signs or symptoms suggestive of stroke.14 According to the various sources CDUS should only be used for patients presenting with concerns of stroke, transient ischaemic attacks, focal neurological signs or carotid bruits.18–21
CDUS, carotid duplex ultrasound.