Health Outcomes Assessment:
The Remaining Questions

In "Postscript: The Remaining Questions" (Medical Care, 2000, 38:9, Supplement II, 290-210), Donald Patrick and Yen-Pin Chiang identify deficiencies in the health outcomes assessment field:

"In particular, there are 4 issues, although we have strived to address them [in a recent 2-day conference], that nonetheless remain largely unresolved in our view. We believe, however, these are issues and concerns of critical importance and deserve much further deliberation as the field moves forward."

1. "Our critical deficiency in relating the measurement metrics to the patients/consumers and clinicians in sufficiently meaningful ways."

2. "It is clearly a daunting task to develop universal instruments that promise conceptual and psychometric equivalence across an array of diverse populations. The prospect of an infinite number of instruments simply based on whatever the characteristics are of the population subgroups is not entirely encouraging or appealing."

3. "... the minimal set of standards to be applied in all applications for defining minimally important change. ... What are the standardized reporting requirements for responsiveness and interpretation, and can these be made generalizable?"

4. "... all the different weights derived from different methods and elicitation procedures are not necessarily meant to capture the same concept."

For those acquainted with the history of physics, these issues will sound familiar. It required 250 years (1600-1850) for the science of thermometry to achieve meaningful metrics (issue 1), universal instruments (issue 2) and general standards (issue 3).

In its earliest stage, the thermoscope (perhaps invented by Galileo in 1593) confused heat with atmospheric pressure (issue 4). Consequently, the thermoscope became the ancestor of both the thermometer and the barometer.

But progress in health outcomes assessment is rapid. An intention of the coming ICOM conference (opposite) is to address these issues head-on.

John Michael Linacre

Patrick D., Chiang Y.-P. (2001) Health Outcomes Assessment: The Remaining Questions. Rasch Measurement Transactions 14:4 p.782

Health Outcomes Assessment: The Remaining Questions. Patrick D., Chiang Y.-P., Linacre J.M. … Rasch Measurement Transactions, 2001, 14:4 p.782

Rasch Publications
Rasch Measurement Transactions (free, online) Rasch Measurement research papers (free, online) Probabilistic Models for Some Intelligence and Attainment Tests, Georg Rasch Applying the Rasch Model 3rd. Ed., Bond & Fox Best Test Design, Wright & Stone
Rating Scale Analysis, Wright & Masters Introduction to Rasch Measurement, E. Smith & R. Smith Introduction to Many-Facet Rasch Measurement, Thomas Eckes Invariant Measurement: Using Rasch Models in the Social, Behavioral, and Health Sciences, George Engelhard, Jr. Statistical Analyses for Language Testers, Rita Green
Rasch Models: Foundations, Recent Developments, and Applications, Fischer & Molenaar Journal of Applied Measurement Rasch models for measurement, David Andrich Constructing Measures, Mark Wilson Rasch Analysis in the Human Sciences, Boone, Stave, Yale
in Spanish: Análisis de Rasch para todos, Agustín Tristán Mediciones, Posicionamientos y Diagnósticos Competitivos, Juan Ramón Oreja Rodríguez

To be emailed about new material on
please enter your email address here:

I want to Subscribe: & click below
I want to Unsubscribe: & click below

Please set your SPAM filter to accept emails from welcomes your comments:

Your email address (if you want us to reply):


ForumRasch Measurement Forum to discuss any Rasch-related topic

Go to Top of Page
Go to index of all Rasch Measurement Transactions
AERA members: Join the Rasch Measurement SIG and receive the printed version of RMT
Some back issues of RMT are available as bound volumes
Subscribe to Journal of Applied Measurement

Go to Institute for Objective Measurement Home Page. The Rasch Measurement SIG (AERA) thanks the Institute for Objective Measurement for inviting the publication of Rasch Measurement Transactions on the Institute's website,

Coming Rasch-related Events
Aug. 11 - Sept. 8, 2023, Fri.-Fri. On-line workshop: Many-Facet Rasch Measurement (E. Smith, Facets),
Aug. 29 - 30, 2023, Tue.-Wed. Pacific Rim Objective Measurement Society (PROMS), World Sports University, Macau, SAR, China
Oct. 6 - Nov. 3, 2023, Fri.-Fri. On-line workshop: Rasch Measurement - Core Topics (E. Smith, Facets),
June 12 - 14, 2024, Wed.-Fri. 1st Scandinavian Applied Measurement Conference, Kristianstad University, Kristianstad, Sweden


The URL of this page is