OASIS Scoring · Overall Anxiety Severity and Impairment Scale

The OASIS is a free, 5-item self-report measure of anxiety severity and impairment that works across any anxiety disorder, making it well suited to ongoing symptom monitoring.

About the OASIS

The Overall Anxiety Severity and Impairment Scale was developed by Sonya Norman and colleagues as a brief, continuous measure of how severe and impairing a person's anxiety is. Rather than asking about one specific disorder, the OASIS is transdiagnostic: it can be used with any single anxiety disorder, with several at once, or with subthreshold anxiety symptoms, which is why it is popular for tracking change in mixed clinical populations.

It is a self-report measure for adults and adolescents, takes about a minute to complete, and is free to use, so it fits naturally into routine measurement-based care alongside disorder-specific screens.

What the OASIS Measures

The OASIS samples five facets of anxiety over the past week:

• Frequency of anxious feelings,
• Intensity of anxiety,
• Avoidance of feared situations or activities,
• Interference with work, school, or home responsibilities, and
• Interference with social life and relationships.

Together these capture both the severity of anxiety and the functional impairment it causes, on a single underlying dimension.

OASIS Scoring & Interpretation

How to Score the OASIS

Each of the 5 items is rated on a 0 to 4 scale reflecting the past week, where 0 indicates little or no anxiety/impairment and 4 indicates extreme or constant anxiety/impairment. The five item scores are summed for a total ranging 0–20. Higher scores indicate greater anxiety severity and impairment. Use the interpreter above to place a total against the validated cut-score.

OASIS Cut-Point

A total of ≥8 is the validated screening cut-score: in a large primary-care sample it correctly classified about 87% of patients for the presence of an anxiety disorder (Campbell-Sills et al., 2009). Because the scale is continuous, the total is also useful as a severity index to track change over time, not only as a pass/fail screen. A positive screen is a screening result that warrants full clinical evaluation, not a conclusion on its own.

Administration

The OASIS takes about 1 minute and is self-administered. Non-clinical staff can hand out and collect the form, but a licensed clinician interprets the score in the context of history and functional impact. Because it is brief and sensitive to change, it is well suited to administration at every visit to monitor treatment response.

Psychometric Properties

The OASIS has a confirmed unidimensional (single-factor) structure with high internal consistency and excellent test-retest reliability, and it shows strong convergent validity with other anxiety measures and weak correlations with unrelated constructs, supporting discriminant validity, in both non-clinical and clinical samples (Norman et al., 2006; Campbell-Sills et al., 2009). It is also responsive to symptom change, which supports its use for monitoring.

Limitations

• Screening, not a clinical conclusion. A positive OASIS indicates symptoms consistent with clinically significant anxiety and warrants full evaluation.
• Not disorder-specific. Its transdiagnostic design is a strength for monitoring but means it does not identify which anxiety condition is present.
• Self-report. Scores reflect the past week and self-perception, so they are best read alongside clinical history and over repeated administrations.

For generalized anxiety specifically, pair with the GAD-7; for broader distress, the DASS-21; for youth anxiety, the SCARED.

Billing the OASIS (CPT 96127)

OASIS administration qualifies for reimbursement under CPT code 96127 (brief emotional/behavioural assessment) when it is scored and documented with clinical interpretation. The AMA allows up to 4 units per encounter; Medicare limits this to 3. Its brevity makes it practical to administer and bill at repeat monitoring visits.