Spotty performance

As previously posted T-Spot TB has been recently FDA approved; according to their FDA approved package insert they have 95.5% specificity and 97.1% sensitivity (click on image for FULL SIZE)




The FDA note:

Using the cutoff of >6 spots, the estimated specificity of T-SPOT. TB was 97.1% (297/306) [95%CI 94.5%-98.6%]

If all the Borderline (equivocal) results are considered all positive or all negative, the specificity of' T-SPOT.TB was either 94.8% (290/306) or 99.0% (303/306), respectively

Seems like the FDA have not accepted the T-Spot "prespecified cutoffs" or the conclusions of any of the data presented and have applied their own range of spots including those "borderline" (click on image for FULL SIZE);



Despite this Oxford Immunotec continue to advertise that T-Spot TB has

• Sensitivity of 95.6%
• Specificity of 97.1%

The FDA have found that both sensitivity and specificity of T-Spot TB are less and the "invalid rate" greater than previously advertised - how humiliating!