Measuring Constructs

Administering surveys to individuals are the best ways to measure the HBM’s constructs. Surveys are lists of questions administered in-person, over the phone, by mail, or online to gather the opinions, feelings, and beliefs of a selected sample. When administering a survey, it is important to consider the wording of the questions, response format (close-ended vs open-ended responses), question placement and sequence, and demographic characteristics of your sample. Public health researchers use surveys to assess a defined population’s opinions and beliefs, identify causes and effects of certain health behaviors, and aid in health promotion, treatment, and prevention (University of Pennsylvania, 2018).

Researchers can use surveys to measure the six constructs of the HBM. For example, if a researcher wants to assess an individual’s perception of the severity of developing lung cancer they can ask “How would getting lung cancer affect your life?” Respondents can either give an open-ended answer or researchers can give them a set of choices that respondents can choose. A common type of survey method is giving respondents a statement and then asking them how strongly they agree or disagree with the statement. This approach to scaling responses is known as a Likert Scale (Communicate Health, 2013). For example, the interviewer may say “Lung cancer would negatively impact my life” and respondents could say if they “Strongly Agreed”, “Agreed”, “Disagreed”, “Strongly Disagreed”, or were indifferent on the matter.

The six main constructs can be divided into three main categories: (1) Constructs that affect individual perceptions, (2) Modifying factors; (3) Constructs that determine likelihood of action.

Constructs that affect individual perceptions include perceived severity and perceived susceptibility. Taking the example of teen pregnancy, we can use surveys to gauge adolescents’ perceived severity and susceptibility.

Some examples of Perceived Susceptibility of teen pregnancy survey questions are:

  • “How strongly do you disagree or agree with this statement: ‘I have unprotected sex often’”
    • Respondent is given Likert Scale with the 5 options stated above
    • If the respondent agrees with the statement, she perceives that she is susceptible to the negative consequences of engaging in unprotected sex, like STDs or teen pregnancy.
    • If the respondent disagrees with the statement, she perceives that she is not susceptible to becoming pregnant.
  • “How strongly do you disagree or agree with this statement: ‘I have had a (or multiple) pregnancy scare(s)’?”
    • Another way this could be asked is ‘My partner has had a (or multiple) pregnancy scare(s)’
    • Respondent is given Likert scale with the 5 options
  • “What are your perceived chances of becoming pregnant?”
    • Respondent is given a five-point scale with lower numbers meaning the adolescent is at low risk and higher numbers meaning the adolescent is at high risk for becoming pregnant

Some examples of Perceived Severity of teen pregnancy survey questions are:

  • “How Strongly do you disagree or agree with this statement: ‘Becoming pregnant as a teen would negatively impact my life and my future’?”
    • Respondent is given Likert scale with the 5 options
    • If the respondent agrees with this statement, she believes that teen pregnancy comes with severe consequences
    • If the respondent disagrees with this statement, she believes that teen pregnancy is not severe
  • “How would becoming a teen parent impact your life and your future?”
    • Respondent is given a five-point scale with lower numbers representing a minimal impact and higher numbers representing a greater impact
  • Do you believe engaging in unprotected sex is risky?
    • Respondent answers Yes or No

Modifying factors include demographics, perceived threat, and cues to action. Taking the example of teen pregnancy again, we can use surveys to gauge these three factors.
Survey questions to measure Demographic characteristics:

  • Asking the respondent their age, gender, race, socioeconomic status, education level, religion etc

Survey questions to measure perceived threat (combination of perceived severity and susceptibility):

  • “How strongly do you disagree or agree with this statement, ‘I engage unprotected sex and believe this will lead to negative health outcomes”
    • Respondent is given Likert Scale with the 5 options
    • If the respondent agrees with the statement, they perceive a threat. They believe that practicing unsafe sex is dangerous and that it can lead to negative health outcomes.

Survey questions to measure cues to action:

  • “How often do you see reminders around school, on social media, or from friends and family to practice safe sex?”
    • Respondent is given a five-point scale with lower numbers representing a lower frequency of reminders seen and higher numbers representing a higher frequency of reminders seen
  • “Do you know anyone who was pregnant as a teenager or gave birth to a child as a teenager?
    • Respondent answers Yes or No

Constructs that determine a person’s likelihood of action include perceived benefits and barriers. Continuing our example of teen pregnancy, we can use surveys to gauge adolescents’ perceived benefits and barriers from practicing safe sex and reducing risks associated with teen pregnancy
Survey questions to measure perceived barriers:

  • “How strongly do you agree or disagree with this statement, ‘I have easy and affordable access to contraceptive methods, including condoms, birth control, or IUDs’?”
    • Respondent is given Likert scale with the five options
    • If the respondent agrees with this statement, he or she does not face many barriers to practicing safe sex
    • If the respondent does not agree with this statement, he or she faces significant barriers to practicing safe sex
  • “How comfortable are you with talking with your partner about contraceptive methods in order to practice safe sex?”
    • Respondent is given a five-point scale with lower numbers meaning the respondent is not comfortable with talking to their partner and higher numbers meaning the respondent is comfortable with talking to their partner
    • If a respondent gives a low number, for example, he or she faces a communication barrier to practicing safe sex

Survey questions to measure perceived benefits:

  • “How important is it for you to graduate from college and find a stable job before having children?”
    • Respondent is given a five-point scale with lower numbers meaning graduating and finding a job is not very important and higher numbers meaning graduating and finding a job is very important to them
    • If a respondent gives a high number, for example, he or she sees the benefits of avoiding teen pregnancy and practicing safe sex
  • “How strongly do you agree or disagree with this statement, ‘Practicing safe sex can help me avoid unwanted or teen pregnancy’?”
    • Respondent is given Likert scale

Survey questions can also be given to measure a person’s self-efficacy:

  • “On a scale from 1-5, with ‘one’ meaning not adept to ‘five’ meaning very adept, how adept are you at using some sort of contraceptive method, like wearing condoms or using birth control?”
    • If respondents gives a low number, for example, they lack self-efficacy in preventing teen pregnancy or practicing safe sex.

Another example where questionnaires were used to measure constructs of the Health Belief Model was during a study to assess predictors of preventive measures for rabies (Morowatisharifabad, 2014). The cross-sectional study was conducted on 204 families who were selected through a group random sampling design from urban families of Abadeh, Iran in 2012. A series of research-design questions were administered to the head of the household, which included either the father or mother, or a member of the family over the age of 15. It was also completed through face-to-face interviews with the participants’ consent and ensuring them about confidentiality of their responses. The questionnaire comprised of several sections. The first section involved general information such as the family size, his/her level of education. The second section consisted of 29 three-way (Yes/No/I don’t know) questions asking participants’ knowledge about different aspects of rabies. This included; animals that would be infected with rabies, ways of getting rabies, symptoms of rabies infection in animals and human, environmental conditions that cause more viability of rabies virus, the possibility of vaccinating animals against rabies, and if the symptoms of rabies appear in humans, is it possible to treat it.

The other sections of the questionnaire were based on the constructs of the health belief model and consisted of specific question for each construct. Each question was to be answered through a score range, (none/some/much/very much), or (yes/no). The scores were based on the different items the participants’ mentioned in their answers, which was then used to calculate the mean and percentage of the participants’ knowledge about rabies.

Question for Perceived Susceptibility:

  • “How much do you think it is possible that you may be infected by rabies?”
    • (None/Some/Much) with (score range 3-9)

Question for Perceived Severity:

  • “In your idea, how much serious is rabies?”
    • (None/Some/Much/Very Much) with (score range 1-4)

Question for Perceived Benefits:

  • “To what extent do you think each of these measures is effective in preventing rabies? Vaccinating animals, reporting suspected cases of the disease to the health center.”
    • (None/Some/Much) with (score range 10-30)

Question for Perceived Barriers:

  • “How much does each of the following factors hinder you to do measures to prevent rabies? Not enough space to keep animals away from the living environment.”
    • (None/Some/Much) with (score range 7-21)

Question for Cues to Action:

  • “Have you ever read a book or pamphlet about rabies?”
    • (Yes/No) with (score range 0-8)

There were also several yes/no questions asked regarding what safety and protective measures the participants took when they encountered domestic animals such as taking care of one at home or getting bit by one.

Questions about Protective Activities:

  • “Did you vaccinate your farm animals?”
    • “If you encounter any scratches or bites by domestic or wild animals, would you wash it with water and soap?”

The results of the study showed that participants’ actions to protect themselves from rabies were strongly correlated with their total knowledge about rabies. Using the health belief model, researchers were able to indicate that participants did not have enough knowledge about cues to actions when infected by rabies, and the environmental conditions they were living in caused them to be more exposed of the virus. As a result, the model revealed that educational programs were necessary for increasing public knowledge about this issue.