4083.0: Tuesday, November 14, 2000 - 8:30 AM

Abstract #13194

Obtaining Fundamental Measurement: From Concrete, Ordinal Counts to Abstract, Interval Measures

William P. Fisher, PhD and George Karabatsos, PhD. Biometry and Genetics, LSU Health Sciences Center, 1901 Perdido Street, New Orleans, LA 70112, 504-568-8083, WFISHE@lsumc.edu

The science of instrument calibration makes it possible for different brands or configurations of the same basic device to produce numeric measures indicating the same amount of a variable. Even when different brands of weight scales are used by different people measuring different samples, two kilograms remains roughly constant across scales, users, and things measured. Fruit and vegetables are sold by weight instead of by count because abstract weights provide fairer estimates of amount than concrete counts do. Unfortunately, health care quality assessments, whether based on patient or hospital surveys, usually rely too exclusively on concrete counts of events or ratings, in a manner analogous to paying the same amount of money for any 7 apples, small or large. Measurement that stops with summed ratings or counted events is the same as treating any 7 apples as the same amount of apple or any 7 marks on unevenly-spaced rulers as the same amount of length. It is often said that no field is scientific unless it is mathematical and quantitative. Does the use of a hodgepodge of incomparable unevenly-spaced scales in the measurement of a variable make a field scientific? Or does science require the abstract equal-interval ruler that stays the same across specific concrete counts, as weight remains constant across groups of apples? This graphical presentation will make the case in favor of abstract measures, with an introduction to their calibration.

Learning Objectives: At the conclusion of this paper, the participant learner will be able to: 1. articulate the difference between counts and measures; 2. show why that difference is vitally important to improving measurement based on surveys and tests; and 3. begin to contribute to the movement toward a new conceptualization of standardized measures

Keywords: Standards, Survey

Presenting author's disclosure statement:
Organization/institution whose products or services will be discussed: None
I do not have any significant financial interest/arrangement or affiliation with any organization/institution whose products or services are being discussed in this session.

The 128th Annual Meeting of APHA