Tpb.measurementTPB Questionnaire A THEORY OF PLANNED BEHAVIOR QUESTIONNAIRE Icek Ajzen
Brief Description of the Theory of Planned Behavior
According to the theory, human behavior is guided by three kinds of considerations: beliefs about the likely consequences of the behavior (behavioral beliefs), beliefs about the normative expectations of others (normative beliefs), and beliefs about the presence of factors that may facilitate or impede performance of the behavior (control beliefs).
In their respective aggregates, behavioral beliefs produce a favorable or unfavorable attitude toward the behavior; normative beliefs result in perceived social pressure or subjective norm; and control beliefs give rise to perceived behavioral control.
In combination, attitude toward the behavior, subjective norm, and perception of behavioral control lead to the formation of a behavioral intention.
As a general rule, the more favorable the attitude and subjective norm, and the greater the perceived control, the stronger should be the of actual control over the behavior, people are expected to carry out their intentions when the opportunity arises.
Intention is thus assumed to be the immediate antecedent of behavior.
However, because many behaviors pose difficulties of execution that may limit volitional control, it is useful to consider perceived behavioral control in addition to intention.
To the extent that perceived behavioral control is veridical, it can serve as a proxy for actual control and contribute to the prediction of the behavior in question.
The following figure is a schematic representation of the theory.
TPB Questionnaire Construction
The following description of questionnaire construction is based on the appendix in Fishbein, M., & Ajzen, I.(2010).Predicting and changing behavior: The reasoned action approach.
New York: Psychology Press.
Formative Research Defining
Before any work can begin, the behavior of interest must be clearly defined in terms of its target, action, context, and time Activity
We could define exercise behavior for at least 20 min, three times pe
Specifying the Research Population
The population of interest to the investigators also must be clearly patients
In this example, only individuals who have just undergone major heart surgery would be included in the research population.
Formulating Items for Direct Measures
Five to six items are formulated to assess each of the theorys major constructs:
Attitude, perceived norm, perceived behavioral control, and intention.
Seven-point bipolar adjective scales are typically employed.
Sample items assessing intention and each aspect of attitude, perceived norm and perceived control are shown below; additional items and instructions to the participants are shown in the sample questionnaire (Part II).
Participants are asked to circle the number that best describes their personal opinions.
Note that the items are formulated to be exactly compatible with the behavioral criterion and to be and experiential aspects
My exercising for at least 20 minutes, three times per week for the next three months would be
bad :: good
pleasant :: unpleasant
TPB Questionnaire norm:
Injunctive and descriptive aspects
Most people who are important to me approve of my exercising for at least 20 minutes, three times per week for the next three months.
agree :: disagree
Most people like me exercised for at least 20 minutes, three times per week in the three months following their major heart surgery
unlikely :: likely
Perceived behavioral control:
Capacity and autonomy aspects
I am confident that I can exercise for at least 20 minutes, three times per week for the next three months.
true :: false
My exercising for at least 20 minutes, three times per week for the next three months is up to : agree
I intend to exercise for at least 20 minutes, three times per week for the next three months.
likely :: unlikely
In the past three months, I have exercised for at least 20 minutes, three times per week.
false :: true
(Note that, in the current example, past behavior may not be a good predictor of future behavior because the past behavior would have occurred prior to the heart surgery.)
Administering a Pilot Questionnaire
Eliciting Salient Beliefs
A small sample of individuals representative of the research population (post-operative patients) is used to elicit readily accessible behavioral outcomes, normative referents, and control factors.
Although the participants can be assembled in groups, the elicitation is done individually in a free response format.
TPB Questionnaire take a few minutes to tell us what you think about the possibility of exercising for at least 20 min, three times per week for the next three months.
There are no right or wrong responses; we are merely interested in your personal opinions.
In response to the questions below, please list the thoughts that come immediately to mind.
Write each thought on a separate line.
(Five or six lines are provided for each question.)
Behavioral outcomes (1) What do you see as the advantages of your exercising for at least 20 minutes, three times per week for the next three months? (2) What do you see as the disadvantages of your exercising for at least 20 minutes , three times per week for the next three months? (3)
What else comes to mind when you think about exercising for at least 20 minutes, three times per week for the next three months?
Normative referents When it comes to your exercising for at least 20 minutes, three times per week for the next three months, there m
Tpb.interventionAccording to the theory, human behavior is guided by three kinds of considerations: beliefsabout the likely outcomes of the behavior and the evaluations of these outcomes (behavioralbeliefs), beliefs about the normative expectations of others and motivation to comply with theseexpectations (normative beliefs), and beliefs about the presence of factors that may facilitate orimpede performance of the behavior and the per; normative beliefs result in perceived social pressure or .
In combination, attitude toward thebehavior, subjective norm, and perception of behavioral control lead to the formation of a.
As a general rule, the more favorable the attitude and subjective norm, andthe greater the perceived control, the stronger should be the persons intention to perform theassumed to be the immediate antecedent of behavior.
However, because many behaviors posedifficulties of execution that may limit volitional control, it is useful to consider perceivedbehavior in question.The following figure is a schematic representation of the theory.Interventions with the TPB 2 Interventions designed to change behavior can be directed at one or more of itsdeterminants: attitudes, subjective norms, or perceptions of behavioral control.
Changes in thesebehavior, the new intentions should be carried out under appropriate circumstances.
Because attitudes, subjective norms, and perceived behavioral control are assumed to bebased on corresponding sets of beliefs, behavioral interventions must try to change the beliefsthat, according to the theory, ultimately guide performance of the behavior.
It is important tothe currently favored term, beliefs that are readily
Pilot work is requiredto identify accessible behavioral, normative, and control beliefs.
Respondents are given aparticipant, or to construct a list of , i.e., a list of the most commonlyThis questionnaire is administered in the second stage of the formative research.
It includesdirect measures of attitudes, subjective norms, perceptions of behavioral control, intentions, andactual behavior.
By using multiple regression or structural equation analyses, we can determinethe relative contributions of attitudes, subjective norms, and perceptions of behavioral control tobeliefs (beliefs strength and outcome evaluations), normative beliefs (strength and motivation tocomply), and control beliefs (strength and perceived power).
By measuring these beliefs, wecertain attitudes, subjective norms, and perceptions of behavioral control.
The beliefs provide asnapshot of the behaviors cognitive foundation in a given population at a given point in time.Once it has been decided which beliefs the intervention will attempt to change, an effectiveintervention method must be developed.
This is where the investigators experience andcreativity comes into play
The theory of planned behavior can provide general guidelines,described below, but it does not tell us what kind of intervention will be most effective.
Wecould consider persuasive communications, perhaps in the form of newspaper ads, flyersce messages.
Alternatively, we might want toInterventions with the TPB 3 try face-to-face discussions, observational modeling, or any other applicable method.
Thepurpose of this third phase of the formative research is to demonstrate that the interventionWhen selecting a target for the behavioral intervention, one obvious consideration iswhether there is much room for change in the designated target.
Consider, for example, anintervention designed to increase breast self-examination among African-American women over40.
If the formative research shows that, on average, women in this population hold verypositive attitudes toward the behavior in question, an intervention designed to make theirattitudes more favorable is unlikely to influence their behavior.
The formative research may,however, reveal relatively low perceptions of control over performing breast self-examinations.If the formative research shows that there is room for change in two or all three predictors, itthe intervention.
Generally speaking, the greater the relative weight of a given factor, the moreConsider, for example, a case where attitudes toward the behavior explain a great deal ofvariance in intentions, subjective norms and perceptions of behavioral control contributerelatively little, and intentions account for most of the variance in behavior.
It would seemreasonable to direct the intervention at behavioral beliefs in an attempt to make attitudes towardthe behavior more favorable, thus affecting intentions and behavior.This is not the only possible approach, however, and it may not even be the most of the relative weights of attitudes, subjective norms, and perceptions ofThese weights are usually interpreted as corresponding to the relative importance of themay have little to do with the relative importance of the different predictors.
Importantly, theyare influenced by the degree of variance in the items used to assess the predictors.
To return tothe above example, imagine that a large proportion of women in the population have lowperceived control over performing breast self-examinations.
Because of the low variability inontrol among an appreciable proportion of womencould produce a considerable increase in the rate of breast the intervention, there may be much more variability in perceived behavioral control,and we may now see a strong coefficient for this factor in the prediction of intentions andInterventions with the TPB 4 The relative weights of attitudes, subjective norms, and perceptions of behavioral controlmay thus not be very good guides for the targeting of an intervention.
So long as a givenpredictor can have a strong impact.
On the other hand, a weak regression or path coefficient maycorrectly
Viewfile.aspx?itemid=212CONSTRUCTING QUESTIONNAIRES BASED ON THE THEORY OF PLANNED BEHAVIOUR
A MANUAL for HEALTH SERVICES RESEARCHERS
Jeremy Grimshaw, Robbie Foy, Eileen F S Kaner, Liz Smith, Debbie Bonetti Centre for Health Services Research
University of Newcastle
21 Claremont Place
United Kingdom ReBEQI WP2
Theory of Planned Behaviour Questionnaires: Manual for Researchers FOREWORDThis manual is a response to a request from heaproject (Research-Based Education and Quality Improvement).It is based on a psychological d Behaviour (TPB; Ajzen, 1988), which evolved from ices research to produce an effective questionnaire to measure the TPB constructs.Advice from the TPB literature (e.g.Ajzen, 1988; Conner & Sparks, 1995; Godin & Kok, 1996) has been integrated, resulting in a guide to writing questionnaires that is based on current practice among TPB researchers.be used to investigate the ealth-related behaviour.
In implementation (or knowledge transfer) evidence-based practice.
tabase, from 1985 to January 2004.
the fascinating but time consuming task of reading the source materials and considering current debates about measurement eir topic of interest.This manual is a tool that may help researchers to fast-track through this process.For those who have the time to investigate This manual has been subjected to lling procedures.We are grateful to many colleagues who reviewed earlier drafts, to workshop participants who used the manual as an translations and comments on the Dutch and ItJill Francis, Martin Eccles, Marie Johnston, Anne Walker, Jeremy Grimshaw, Robbie Foy, Eileen Kaner, Liz Smith, Debbie Bonetti ReBEQI WP2
Theory of Planned Behaviour Questionnaires: Manual for Researchers measurement of subjective measurement of subjective norm: measuring normative beliefs and motivation to comply.........186.2.1Stages of test these items by asking about five respondents to answer the questions and tell you whether they have any difficulty answering them.
If necessary, modify the wording of the measurement of perceived behavioural control ( measures of PBC: Measuring control beliefs and their perceived power to influence behaviour227.2.1Stages of the population, clinical condition and behaviour of the and piloting the and content of of questions in the the questionnaire and creating the second forms of the questionnaires into other study: Practical sample size is aspects of survey methodology that need to be kept in up the WP2
Theory of Planned Behaviour Questionnaires: Manual for Researchers ReBEQI WP2
Theory of Planned Behaviour Questionnaires: Manual for Researchers Attitude toward the behaviour is a persons overall evaluation of the behaviour.It is assumed to have two components which work togethcorresponding positive or negative judgements about each these features of the behaviour (outcome Subjective norms are a persons own estimate of the social pressure to perform or not perform the target behaviour.
Subjective norms are assumed to have two components which work in interaction: beliefs about how other people, who may be in some way important to the person, would like them to behave (normative beliefs), e.g.I feel pressure from patients to refer them for an x-ray) and the positive or negative judgements about each belief (outcome evaluations), e.g.in regard to my nk I should do is important/ unimportant).
Perceived behavioural control e extent to which a person feels abtwo aspects: how much a person (e.g.low control over measuring blood pressure if the BP machine often malfunctions); and how confable to perform or not perform the behaviour illed in measuring blood pressure).It is determined by control beliefs about l and internal factors to orming of the behaviour (e.g.
Whether I measure a patients blood pressure is entirely up to me; I could measure my patients blDirect measures and indirect (belief-based) measures With the exception of behaviour, the variables in the TPB modeconstructs.Each predictor variable may be measuroutcome evaluations.Direct and indirect measurement approaches make different assumptions about ch is perfect.
When different methods are tapping the same construct, scores are recommended that both be included in TPB questiSection 8.4 about brief forms of the questionnaire).This manual explains how to construct questions for both types of measure.
It is important to establish the reliability (Everitt, 1996) of each measure.For direct measures, one form of reliability may be established using an index of internal consistency (to determine whether the items in the scale are measuring the same construct).However, because people can quite logically hold both positive and negative beliefs about the same behaviour, it is not appropriate to assess the reliability of indirect measures using an internal consistency criterion.For example, someone may believe that referring patients withexpose these patients to unnecessary radiation.Equally, a GP may be highly motivated to comply with eagues but not at all motivated to comply with the patients.Hence, it does not make sense to eliminate some of these beliefs from overall measures on the grounds of low or negative correlations among them.It is necessary to use test-retest reliability (or temporal stability) for this purpose.ReBEQI WP2
Theory of Planned Behaviour Questionnaires: Manual for Researchers This section describes three methods of measuring intentions.WePerformance, because in some situerve actual performance using the same measurement scale, and this direct comparability could be useful for some studies.In the TPB literature, where most research has been about individuals own health-related behaviour (e.g.
smoking, exercise), Generalised Intention tention Simulation (Method 3) could be a more valid proxy measure for actual behaviour, because it more closely approximate