Objective To assess the cost-effectiveness of implantable loop recorders (ILRs) and tilt testing (TT) to direct pacing therapy in people with recurrent episodes of transient loss of consciousness that are adversely affecting their quality of life or represent a high risk of injury and are suspected to be vasovagal.

Design Decision analytical modelling was used to estimate the costs and benefits of diagnostic testing including the costs and benefits of treatment for several clinically important arrhythmias following diagnosis.

Setting A UK National Health Service and personal social services perspective was taken.

Patients People with recurrent episodes of transient loss of consciousness that are adversely affecting their quality of life or represent a high risk of injury and which are suspected to be vasovagal.

Interventions The diagnostic test strategies compared were TT alone, TT followed by ILR (if TT ‘negative’), ILR alone and no further testing.

Main outcome measures Benefits measured using quality-adjusted life years and incremental cost-effectiveness ratios (ICER) are reported.

Results The ICERs for TT alone, ILR alone and TT followed by ILR were £5960, £24 620 and £19 110, respectively, compared with no testing. ILR alone was extendedly dominated by the other strategies, meaning that it is never the most cost-effective option. Sensitivity analysis found that the cost-effectiveness estimates were robust despite the areas of uncertainty identified in the evidence and assumptions used to inform the model.

Conclusions TT alone is likely to be the most cost-effective strategy in this population.