Self-esteem will be measured by the Rosenberg Self-Esteem Scale.
Pain intensity will be measured by using a visual analog scale representing a continuum of intensity from no pain to pain as bad as it can be.
The term operationalization is the transformation statement found in Gibbs’s model.
Like the transformational statement, operationalization is the process of transform- ing a concept from an abstract indicator into an empirical indicator. The opera- tionalization process includes making decisions about the way a concept will be measured, selecting the empirical indicators to be used to communicate its meaning, and selecting the procedures for measuring. In this process, based on theoretical and empirical work, the researcher or evaluator seeks to understand the meaning of the concept and the best approach to measure the concept for a specific study. Usually re- searchers operationalize a concept for a specific study. Two researchers might employ the same theoretical definition of a concept but choose different empirical indicators of the concept. Thus, we find operational definitions generally more restrictive and situation-specific than theoretical definitions.
habits and passenger helmet use. In contrast, items written for the scale are all related to attitudes about using helmets, and all response options are the same.
Single-Item Versus Multiple-Item Scales
Spector (1992) notes that single-item assessments of concepts are unsatisfactory mea- sures of people’s opinions, attitudes, or feelings because responses to single items lack precision, tend to change over time, and are limited in scope.
Take this item related to motorcycle helmets:
People who ride motorcycles should wear helmets every time they ride.
Yes No
Persons asked to respond to this item are forced to choose between one of two broad options, thus limiting their range of possible responses to yes and no. Other, more exact choices are not possible; thus, precision of responses is limited. The item also mea- sures how people are feeling in general about wearing motorcycle helmets at the time when they answer the item. People who are undecided might answer favorably one day and unfavorably another day.
Multiple-item scales overcome these difficulties by expanding the number of items assessing various aspects of the concept and providing more response options. Adding items about wearing helmets under different circumstances allows people to rate hel- met use on different dimensions, thus expanding the scope of the measure. By pro- viding more options with which to rate each item, the researcher enhances precision.
Rating feelings on helmet use items on a four-point agree/disagree scale allows people to rate the intensity of their feelings and provides response options for people who favor helmet use only under certain circumstances. The instrument improves the reliability or stability of responses over that of single-item measures, because a response to any one item in a scale does not overly influence the total score. For example, the total score for a person who mistakenly answers disagree on an item one time and later corrects that error differs by only a few points, provided that all the other responses on the scale re- main the same. Scale responses also permit the categorization of people into groups based on the intensity of their feelings about helmet use, unlike single items that require a yes or no response. For example:
People who ride motorcycles should wear a helmet every time they ride.
Strongly disagree Disagree Agree Strongly agree
EXHIBIT 6.1. SAMPLE SURVEY AND SCALE ITEMS, DEMONSTRATING DIFFERENCES.
Survey Items
Instructions: Please answer the following questions about motorcycle and helmet use.
What type of motorcycle do you ride?
How often do you ride?
Daily
2–6 days/week 1–4 days/month Less than 1 day/month
How often do you wear a helmet when you ride?
Every time Most of the time Sometimes Hardly ever Never
How often do you ask your passenger to wear a helmet?
Every time Most of the time Sometimes Hardly ever Never
Where do you ride your motorcycle? (Check all that apply) Streets near home
Side streets Dirt trails Expressway
When I ride my motorcycle, I usually ride at the speed limit or less.
Yes No
Concept Selection
The need for a new scale generally arises from one of two situations: no scale exists that measures the concept, or no scale exists that measures the concept in the popu- lation of interest to the researcher. Because health behavior research is a fairly new area of study and because so many concepts are available to study, the lack of a measure for a health behavior concept tends to be fairly common. In addition, our theories in health behavior often require that we develop new measures based on the behavior that we wish to study. For example, social cognitive theory requires that mea- sures of self-efficacy be behavior-specific. If we wanted to measure individuals’ degree of self-efficacy related to the use of motorcycle safety, we would first search for an instrument that measured motorcycle safety self-efficacy. If none existed, we would
Scale Items
Instructions: Please circle the word that best describes the way you feel about each of the following statements on motorcycle helmet use.
All people who ride motorcycles should wear helmets.
Strongly disagree Disagree Agree Strongly agree
Motorcycle helmets are too hot to wear.
Strongly disagree Disagree Agree Strongly agree
Most of my friends would make fun of me if I wore a motorcycle helmet.
Strongly disagree Disagree Agree Strongly agree
Most people look stupid wearing motorcycle helmets.
Strongly disagree Disagree Agree Strongly agree
Motorcycle helmets save lives.
Strongly disagree Disagree Agree Strongly agree
Motorcycle helmets should be worn only when traveling on the expressway.
Strongly disagree Disagree Agree Strongly agree
need to develop an appropriate self-efficacy scale before conducting the study. Other examples of theory-based constructs that require behavior-specific instruments include outcome expectations (social cognitive theory); stages of change (transtheoretical model); and perceived susceptibility, barriers, and benefits (health belief model).
A second possible reason for developing a new measure is that the existing mea- sure of the concept is inappropriate for the intended population. For example, several measures of social support for adults exist. However, if a researcher wanted to measure social support among children and no scale existed, he or she would have to modify one developed for adults or create a new one.
Researchers need to be aware that some theoretical concepts are not amenable to measurement. A common example of a nonmeasurable concept comes from Freud’s psychoanalytic theory. Because of their psychodynamic nature, the ego, id, and super- ego are not amenable to self-report measures. Likewise, though death might be a vari- able in some situations (for example, resuscitated, brain-dead), the afterlife is not amenable to measurement.
A researcher who accepts the challenge of developing a new measure must first select the concept and then conduct a concept analysis. The concept analysis allows the researcher to develop a solid understanding of the concept and the ways in which people use and interpret the concept. Only after the completion of the concept analy- sis, the clarification of the theoretical definition, and the statement of the variable should the researcher begin to write items. Because of the importance of concept analysis to the scale development process, we will devote the remainder of this chap- ter to a discussion of concept analysis. In Chapter Seven, we will discuss item writing.