Abstract

Sir Archie Cochrane and Sir Austin Bredford Hill requested to answer three short questions before implementing a new healthcare service into daily clinical practice: CAN IT WORK? DOES IT WORK? IS IT WORTH IT? For implementation of this 3-step-CDI-strategy we propose the consecutive completion of three different types of studies.

First, a Randomised Controlled Trial (RCT) to confirm that it CAN WORK, i.e. to demonstrate efficacy under Ideal Study Conditions (ISC). Second, a Pragmatic Controlled Trial (PCT) to confirm that it DOES WORK, i.e. to demonstrate effectiveness under Real World Conditions (RWC). Third, a Complete Economic or Cost-Effectiveness-Analysis (CEA) to demonstrate that IT IS WORTH IT, i.e. to demonstrate the value [needless to say] under RWC from the patient and the societal perspectives.

Unfortunately, there exist still different concepts on the appropriateness of different tools (RCT, PCT, CEA) for assessment of different effects (efficacy, effectiveness, value) under different conditions (ISC, RWC). There is probably no rational condition between the two ‘extremes’ of ICS and RWC. One may measure effects either under ISCs or RWCs. Both conditions and the interventions under these conditions can be distinguished clearly by five criteria. The goal of the intervention, the respect of patient autonomy, the legitimised application of the intervention, the application of not legitimised interventions, and finally the value generated by the intervention.

These details will be presented in four tables. First, the tree requests of Sir Archie Cochrane and Sir Austin Bredford Hill. Second, the 3-step-CDI-approach we propose. Third, the description of differences of efficacy, effectiveness, and value, and finally and fourth, the detailed differences in the 14 steps of a RWC, PCT or RCT.

The function of this 3-step-CDI-approach is a prototype of the more practicable ICE-3-step-tool that will be presented at the next meeting.