The National Institute for Health and Care Excellence (NICE) Diagnostics Assessment Programme (DAP) evaluates the cost-effectiveness of diagnostic technologies. A decision-making process benchmarking the incremental cost-effectiveness ratio (ICER) against a threshold while considering decision-modifying factors is common to NICE evaluations. This study investigated whether DAP decisions are consistent with the ICER thresholds described in the DAP manual, and to assess the impact of decision-modifying factors.
DAP evaluations published before March 2018 were reviewed, and the following items were extracted: diagnostic technologies evaluated, decision problems assessed, Diagnostics Advisory Committee (DAC) decisions, incremental quality-adjusted life years (QALYs), incremental costs, ICERs considered to be most plausible by the DAC, and decision justifications.
All 30 evaluations were reviewed; 8 were excluded because the DAC concluded there was “insufficient evidence” for decision making. In the remaining 22 evaluations, 91 decision problems were identified for further analysis, of which 52, 15, and 24 received “recommended,” “not recommended,” and “not recommended–only in research” guidance, respectively. The overall consistency rate of the DAC decisions with the £20 000/QALY threshold was 73.6%. Diagnostic technologies that were not recommended, despite an ICER less than £20 000/QALY, were associated with a larger number of decision-modifying factors favoring the comparator, versus recommended diagnostic technologies with ICERs less than £20 000/QALY. For technologies with ICERs greater than £20 000/QALY, the number of decision-modifying factors was comparable for positive and negative recommendations.
Most DAP decisions were consistent with the ICER threshold. However, cost-effectiveness was not the only determining factor in decision making; recommendations also considered patient- and healthcare-centric factors and uncertainty.