and international standards, as described in Chapter 3. Technological adequacy was not directly defined but informally described as whether a technology is "good enough for now" for the intended purposes and circumstances. The researchers argued that evaluators need better strategies for assessing the adequacy of the

  • input data—including its quality (e.g., image resolution, sound quality), the speed of the equipment for encoding and delivering it to the main transmission medium, and the quality of any data compression and other pretransmission modification of the data;
  • transmission of data—based on the bandwidth (information carrying capacity) of the communications medium, its cost, and practicality; and
  • display of data received—including the quality of the images, sound, or other information, and the options for enhancing or otherwise manipulating the information (e.g., increasing or decreasing contrast).

The CHPR discussion of medical effectiveness is consistent with the definition offered in Chapter 1 (results under normal conditions of use) and emphasizes the need for comparison with conventional services. The discussion focuses on practical strategies such as (a) narrowing the range of conditions and indicators of effectiveness to be studied; (b) establishing minimal levels of diagnostic accuracy for particular applications and conditions; and (c) assessing the appropriateness (a combination of effectiveness, cost-effectiveness, and acceptability to patients and physicians) of using a technology in specific health care environments (e.g., rural areas) and for specific clinical problems and types of patients (e.g., gynecological examinations).

The proposed taxonomy sorted telemedicine applications according to the level of evidence or consensus about their effectiveness, a key criterion for coverage. Applications or aspects of evaluations can be described as (a) effective; (b) probably effective; (c) not demonstrated as safe and effective; or (d) new and untested.

For purposes of HCFA coverage policy (as governed by statutes and regulations), even the first category—applications that are judged effective—may raise additional questions about implementation and economic impacts that warrant pilot tests designed to guide explicit



The National Academies | 500 Fifth St. N.W. | Washington, D.C. 20001
Copyright © National Academy of Sciences. All rights reserved.
Terms of Use and Privacy Statement