NHS ltbi cost effectiveness study

Hot off the presses is the Different screening strategies (single or dual) for the diagnosis of suspected latent tuberculosis: a cost-effectiveness analysis.

A reasonably contentious statistical analysis heavily reliant on various assumptions.

this conclusion is sensitive to screening test assumptions and LTBI prevalence.  

At first glance it appears that the study appears to be primarily concerned with the costs of diagnosis, not the long term consequences of diagnosis

In this study, a decision tree was constructed to measure the costs and clinical outcomes  (i.e. effectiveness) over a 2 year period

2 years is not enough

...a shorter timeframe underestimates the number of downstream active TB cases 

and this restraint placed IGRA at a disadvantage

the more effective strategies in our model (T-SPOT.TB and QFT-GIT only) will become more cost effective if a longer timeframe was used.

Quality of Life Years was not considered

Our analysis did not include this measure

nor were other costs arising from ill health

did not include costs to the wider society i.e. costs incurred on patients, costs due to death, etc.

Despite various limitations of the study some opinions were held to be true

IGRA single screening does cost more (higher testing costs) but less money is spent on false negatives. Less false negatives means fewer people will progress to active disease, resulting in these strategies being the most effective (prevents most cases of post-primary TB). 

Budgetary constraints were critical

healthcare institutions prefer to examine how implementation of a new clinical intervention affects their annual budget rather than long term overall costs

..the more effective strategies in our model (T-SPOT.TB and QFT-GIT only) will become more cost effective if a longer timeframe was used. Similarly wider transmission underestimates the costs of less effective strategies.

whilst TST consistently got the thumbs down

The TST alone strategy had the lowest test costs but this strategy incurred the highest costs resulting from test inaccuracies, particularly the costs incurred on false positive results.

I guess the conclusion was unavoidable

Nonetheless, using the IGRA, whether in a single or dual strategy, is always cheaper than using only the TST.

.