Document Type


Date of Degree

Spring 2011

Degree Name

PhD (Doctor of Philosophy)

Degree In

Industrial Engineering

First Advisor

Schnell, Thomas

First Committee Member

Kusiak, Andrew

Second Committee Member

Thomas, Geb

Third Committee Member

Cook, Thomas

Fourth Committee Member

Wilder, David


Comfort is a sensation and state of being that many people seek when they are working in the office, driving in a car, flying on an airplane, or laying in a hospital bed. The literature identifies many definitions and interpretations for comfort and discomfort, and many different ways that researchers have tried to measure comfort and discomfort. de Looze proposed a model to explain the relationship between comfort and discomfort using three key components: (a) the human, (b) the product, and (c) the environment. This dissertation added a measurement component to the model.

In a repeated measures design, subjects (n=35) sat in three different office chairs for 60 minutes each on two different dates. Researchers collected subjective survey data and objective electronic data related to perceived sitting comfort and discomfort while participants completed office computer tasks. Data were analyzed to predict and quantify office worker seated comfort and discomfort using linear modeling and neural network modeling.

Correlation values from the linear regression model developed in this experiment were R2 < 0.70, while the single hidden-layer neural network model predicted the comfort/discomfort responses with a higher correlation (R2=0.997). The 35 subjects in the study perceived measurable comfort differences between the three chairs tested. Subjective questions that treated comfort and discomfort in a non-linear relationship discriminated chair differences better than questions using a linear relationship. There was no significant difference between male and female comfort/discomfort responses. Comfort ratings decreased over time, while discomfort increased over time; at least 45-minute comfort testing is needed to understand subjects' comfort/discomfort in a particular office chair.

Five common factors that were important to the model included: (a) fit of the product to the person, (b) the features of the product itself, (c) the time spent with the product, (d) the subjective questions, and (e) the objective pressure measurements.


comfort, discomfort, model, objective measure, pressure map, subjective measure


xvi, 210 pages


Includes bibliographical references (pages 201-210).


This thesis has been optimized for improved web viewing. If you require the original version, contact the University Archives at the University of Iowa:


Copyright © 2011 Scott Openshaw