This paper focuses on test cost reduction for RF circuits based on the use of an indirect test strategy. The implementation of a two-tier adaptive test flow is investigated, in which only circuits with a sufficient prediction confidence level are evaluated by the indirect test while others are re-evaluated by specificationbased test. A methodology is presented that permits to explore different tradeoffs between test quality and test cost and to make pertinent choices for the efficient implementation of such a test flow. The methodology is applied to a front-end RF circuit designed for WLAN applications and results show that substantial test cost reduction can be achieved without compromising the test quality.