At the time of interview, there seemed little prospect that
this approach was likely to change. In 2003, however, costeffectiveness analysis had become compulsory part of the
process, yet it did not involve the use of an associated
threshold. And on this basis, we press the fourth insight
of the regulatory governance perspective on HTA: that the
emergence and continuing function of national IAs for HTA
follows a broadly evolutionary pattern in which contextual factors play an important mediating role.