19/01/06 21:28:17.91 ygrq5fyC.net
Predictive Values Based on Integration of Pretest Probability and Diagnostic Test With Flu Score 3* Using
Test and Treatment Thresholds of 10% and 50%, Respectively
Season/Risk Category
Probability of
Influenza (%) Comment
Not flu season (2.5%)
Low risk (0–2) 0.4 Neither test nor treat
Moderate risk (3) 2.1 Neither test nor treat
High risk (4–6) 6.5 Neither test nor treat
Shoulder (10%)
Low risk (0–2) 1.9 Neither test nor treat
Moderate risk (3) 8.4 Neither test nor treat
High risk (4–6) 23 Order rapid test. Probability of flu is 84% if positive and 8% if negative.
Flu season (30%)
Low risk (0–2) 6.8* Neither test nor treat
Moderate risk (3) 26 Order rapid test. Probability of flu is 84% if positive and 8% if negative.
High risk (4–6) 54 Treat empirically via option 1 (consider empiric therapy if high risk for
complications) or option 2 (consider rapid test 95% if positive and
25% if negative).
*Flu score 3 assigns 2 points for fever plus cough, 2 points for myalgias, and 1 point each for duration 48 hours and chills or sweats.
doi: 10.3122/jabfm.2012.01.110161 Clinical Decision Rule for Influenza 61