OBJECTIVES: Relative effectiveness assessment procedures are a critical step of HTA. Some evaluation procedures may need to resort on adjusted indirect comparisons, such as network meta-analysis (NMA), to assess the therapeutic value of the pharmacological intervention. The aim of this study is to assess if there is a relationship between the directness of evidence supporting the relative effectiveness assessments and the identification of added therapeutic value (ATV).

METHODS: Relative effectiveness assessments produced between 2018 and 2021 by 6 HTA bodies (NICE [England and Wales], SMC [Scotland], HAS [France], AEMPS [Spain], SiNATS [Portugal] and IQWIG [Germany]) were reviewed. Data on the pharmacological intervention, comparator(s), data sources and conclusions of therapeutic value was retrieved. Direct evidence reflects evaluations informed by the same comparator(s) and studies that integrated the clinical development program of the pharmacological intervention, representing direct links to assess the health outcomes. Indirect evidence represents the opposite. The qui-square test was applied to explore a possible relationship between the directness of the evidence and the identification of ATV.

RESULTS: Of the 987 relative effectiveness assessment procedures analyzed, 717 were exclusively supported by the direct evidence. Of those, 531 (74.06%) concluded for ATV, 63 (8.79%) for equivalence, 13 (1.81%) were inconclusive, and 110 (15.34%) did not recognize therapeutic value. A total of 270 procedures were informed by indirect evidence. Of those, 199 (73.70%) concluded for ATV, 31 (11.48%) for equivalence, 12 (4.44%) were inconclusive, and 28 (10.37%) did not recognize therapeutic value. The chi-square test did not find a relationship between the directness of the evidence and identification of ATV, except for IQWIG reports only (indirect evidence was related with less chance of ATV identification).

CONCLUSIONS: These results suggest that there is no relationship between the directness of the evidence supporting the relative effectiveness assessment procedures and the identification of ATV.