Developing and Improving Measurement Methods - Evaluation Methods in Biomedical Informatics - page 182

FIGURE 6.9. Delphi technique.
previous opinion. Judges continue to be asked for their opinions on each
case until a convergence criterion is met. This technique is well established
in a variety of fields 30 and is now being applied successfully in biomedicine. 31
Conclusion
This completes our excursion into the world of objectivist measurement. In
this chapter and its two predecessors we have demonstrated the importance
of measurement to sound objectivist study. The attention in the previous
chapter to measurement theory, and in this chapter to technique, was moti-
vated by the chronic paucity of measurement instruments in biomedical
informatics, resulting in the need for investigators to develop and validate
their own measurement approaches. We close almost where we began, by
encouraging investigators who develop measurement methods to publish
their measurement studies, so other investigators may benefit from their
labors. We move in the following chapters to exploration of objectivist
demonstration studies. Everything that follows in Chapters 7 and 8 assumes
that measurement issues have been resolved, in the sense that the reliabil-
ity and validity of all measurement instruments employed in demonstration
studies are known.
Answers to Self-Tests
Self-Test 6.1
1. Predicted reliability is 0.432, which is not usually acceptable.
2. The standard error of measurement is 0.34.