1. Outbreak Investigation Methods from Mystery to Mastery
I is for Investigation
Welcome to Session 4 of the I is for Investigation training series from the UNC Center for Public Health Preparedness.
Outbreak Investigation Methods from Mystery to Mastery

2. Interviewing Techniques
Session IV
Interviewing Techniques
This is the fourth lecture in the series, “Outbreak Investigation Methods: From Mystery to Mastery.” This session will cover interviewing techniques.

3. Session Overview Overview of interviewing methods
Standardizing interviews
Interviewer training
Interviewing techniques
Confidentiality
In this session, we will discuss the different methods of interviewing, standardization of interviews, interviewer training, including interviewing techniques and respondent confidentiality.

4. Learning Objectives
Understand the advantages and disadvantages of different interview methods
Identify strategies to reduce interviewer error
Understand topics to address in interviewer training
Understand confidentiality concerns of both the respondent and the outbreak investigator
Upon completion of this session, you will:
Understand the advantages and disadvantages of different interview methods
Identify strategies to reduce interviewer error
Understand topics to address in interviewer training
Understand confidentiality concerns of both the respondent and the outbreak investigator

5. Basic Steps of an Outbreak Investigation
Verify the diagnosis and confirm the outbreak
Define a case and conduct case finding
Tabulate and orient data: time, place, person
Take immediate control measures
Formulate and test hypothesis
Plan and execute studies
Implement and evaluate control measures
Communicate findings
Before beginning this session, let’s review the basic steps of an outbreak investigation. Remember that in reality, some of these steps may occur simultaneously or in a different order.
First, we must verify the diagnosis and confirm that there is actually an outbreak occurring. Next, we need to create a preliminary case definition and conduct active case finding. Once we have information from some cases, we need to compile and review it. Then we implement preliminary control measures. After that, we formulate and test a hypothesis, and plan and execute additional studies based on the preliminary results. Finally, we implement and evaluate control measures and communicate our findings.
Interviewing techniques can be applied with steps 2 and 5 of an investigation.

6. Role of Interviews in Outbreak Investigations
Data collection
Case identification
Risk factor identification
Hypothesis generation
The primary purpose of an interview is to collect data. In an outbreak investigation, interviews can identify cases, point to possible risk factors, and assist with generating hypotheses.

7. Questionnaire Design and Interview Method are Related
Length and format of questionnaire
Question types used in a survey
Cost considerations for survey implementation
Whether a questionnaire is interviewer administered or self administered, the design of the questionnaire is a key consideration in the interview method. On the other side of the coin, the interview method is a key consideration in the questionnaire design. The design of the questionnaire and the method of interview affect the length and format of your questionnaire and the types of questions you use. The choice of interview method may also be impacted by cost considerations.

8. Advantages and Disadvantages
Interviewing Methods
Advantages and Disadvantages
Let’s now discuss the advantages and disadvantages of the interviewing methods.

9. Interviewing Methods Interviewer administered Self administered
Face-to-face
Telephone
Self administered
Mailed-out
Web-based
There are two main types of interviews – interviewer administered and self administered. Face-to-face and telephone interviews are types of interviewer administered methods, while questionnaires that are mailed out, ed, or web-based are types of self-administered interviews. During an outbreak investigation, questionnaires are often interviewer-administered; however, you may find situations where one of the self-administered methods is more appropriate or efficient.

10. Face-to-Face Interview
Advantages:
Higher response rate
Longer survey instrument
More complex skip patterns
More accurate recording of responses
Less item non-response
Appropriate for hard to reach populations (e.g., illiterate, institutionalized)
Face-to-face interviews tend to have higher response rates because an interviewer standing in your home is more difficult to ignore than a piece of mail or someone on the telephone.
Face-to-face interviews can be longer with more complex skip patterns because a trained interviewer will be administering the questionnaire. Because a trained interviewer conducts face-to-face interviews, responses are often recorded more accurately, and more specifically, fewer questions are left without a response (this is known as item non-response).
Finally, face-to-face surveys are appropriate for populations that are hard to reach by phone or mail, like the illiterate, homeless, or institutionalized.

11. Face-to-Face Interview
Disadvantages:
Costly
Potential for interviewer error
Less anonymous than self-administered
Potential for dishonesty
Safety of interviewers
There are some disadvantages to face-to-face interviews. First, they can be costly, due to personnel time required to invest in conducting the interviews.
There is also potential for interviewer error. For example, since the interviewer usually knows the disease status of the participant, he or she may use a certain tone of voice or specific body language to indicate what he or she thinks the respondent should or will say. In addition, there are generally multiple interviewers conducting interviews during an outbreak investigation, each with a different way of interacting with respondents.
Face-to-face surveys are less anonymous than self-administered questionnaires. Lack of anonymity may motivate persons to under-report socially undesirable behavior and over-report socially desirable behavior. For example, in a face-to-face interview a participant may be embarrassed to admit his daily alcoholic intake, or fear admitting the use of illicit drugs. On the other hand, if a question is about diet, a person may over-report his vegetable consumption to appear to have a more healthy diet. Note that an interviewee can be less than honest in almost every other type of data collection method, but the desire to present oneself in what is perceived as a good manner is often greater when the interviewer and participant meet face-to-face.
In face-to-face interviews, particularly those that take place in the field, interviewer safety is a major consideration. For example, interviewers should not approach a property that is gated or marked “No Trespassing” without permission.

12. Telephone Interview Advantages: Higher response rates than mailed
Less costly than face-to-face
Quicker access to participants
Supervision of interviewers feasible
Can collect more sensitive information
Survey design can be more efficient
Telephone interviews are an alternative interviewer-administered method. Advantages of telephone interviews include higher response rates than self-administered mailed surveys and cost less than face-to-face interviews. Access to participants is usually faster for phone interviews, and interviewers can be supervised to reduce interviewer error. Often, it is easier to collect sensitive information via this method, since the interviewee may feel more comfortable revealing sensitive information via telephone than when they have to look an interviewer in the eye. Finally, the design of the survey may end up being more efficient.

13. Telephone Interview Disadvantages:
Lower response rates than face-to-face
Shorter questionnaires used
Unable to capture important visual information
Visual symptoms such as rash
Working conditions
Under-coverage
No land lines
Unlisted land lines
The disadvantages of telephone interviewing are lower response rates than face-to-face interviews. In general, the questionnaires have to be shorter than face-to-face interviews, as people will not tolerate being on the phone for extended periods of time. Additionally, the interviewer is unable to capture important visual information such as a rash on a respondent or poor working conditions. There also may be under-coverage among certain populations who do not have home telephones or listed numbers.

14. Mailed Questionnaire Advantages:
More anonymous - may collect more honest responses
No interviewer error
Less expensive
Respondent has more time to think about questions
Advantages of mailed questionnaires are that they are more anonymous, and therefore may collect more honest responses, and there is no interviewer error.
Mailed questionnaires also tend to be less expensive, and respondents have more time to think about responses to the questions versus when they are in a face-to-face interview setting.
Mailed surveys may work best when they target specific groups such as a membership list for a professional organization or all clients seen in one medical facility over the past calendar year. But because of the obvious delay in time for mail to be delivered to respondents and then returned to you, you will probably not use this interviewing method for an outbreak investigation with an urgent need for public health action.

15. Mailed Questionnaire Disadvantages: Questionnaire must be simple
Higher item non-response
Lower response rate
Data collection takes more time
Sample population must be literate
Coverage / frame deficiencies
One disadvantage of mailed surveys is that questionnaires must be simple. There also tends to be higher item non-response, that is people will skip questions inadvertently. Often times even a well organized and easy to follow questionnaire can have pitfalls. For example, even if you ask respondents to give only one answer to a question, many people will choose multiple responses.
In addition, response rates are lower for mailed surveys, data collection takes much more time than with telephone or face-to-face, the sample population must be literate, and there are coverage and frame deficiencies.
Coverage and frame deficiencies refer to the lack of a comprehensive list of addresses for households in the U.S. For this reason, mail surveys are not used for general population surveys.

16. Web-Based Questionnaire
Advantages:
Among some populations, most people may have access to the Internet /
Can work through social media
Inexpensive and fast
No data entry required
Improves data quality
Many vendors send data in a variety of formats
While mailed surveys may be too time consuming, web-based questionnaires may prove very useful for outbreak investigations in certain circumstances.
Among many populations, such as students or employees in an office, a large percent of people will have access to both the Internet and . Internet and access will only improve among the general population over time. Web based surveys can be inexpensive and fast.
There is no data entry required on behalf of your health department staff when you implement Web based questionnaires because all responses are saved in a back-end database. This process has the potential to improve the quality of the data, because fewer data entry errors are made. Many vendors offer survey capacity via the Internet. These vendors can send collected data to your health department in a variety of formats for data analysis.
Some vendors allow you to develop the survey instrument on-line, so there is no need to download any software. Some vendors will keep track of all the surveys you have done, so you can reuse a questionnaire again in the future.

17. Web-Based Questionnaire
Disadvantages:
Requires access to Internet
Computer hardware or software limitations or glitches
Potential for multiple responses from one individual
Potential for responses from non-sampled respondents
Contacting the sample population
The most important limitation to using web-based questionnaires is that it requires access to the Internet, which may be limited among certain population groups of interest or in specific situations. Other disadvantages include:
Completion of the questionnaire relies on the respondent’s Internet connection and can be hampered by any glitches with the computer’s hardware or software, including any required updates or plug-ins for completing the questionnaire.
With web-based questionnaires, you also run the risk of getting multiple responses for a single individual or of having non-sampled persons complete the survey.
In addition, you would need some way to contact the sampled individuals to alert them of the questionnaires. Sending a cover letter and instructions via is a common approach, but it requires knowing everyone’s address. Other approaches can cast a wider net, such as running a radio spot with the web address or networking through social media, but these approaches may result in a low response rate or may not be efficient in reaching the intended population.

18. Standardizing Interviews
Now we will discuss some practical techniques for improving interviewing skills related to interviewer-administered face-to-face and telephone questionnaires by employing standard delivery techniques that can be used across interviews and interviewers.

19. Standardizing Interviews
Minimize error, yielding better data quality
Standard instrument
Standard action of interviewers
The goal of standardizing interviews is to minimize error, thereby yielding better data quality. By standardizing both the survey instrument and the action of the interviewers, interviewer error can be minimized. To improve the quality of our data, we must have standardization among and between interviewers.

20. Interviewer Error Defined Types
Deviation from expected answer due to the effects of interviewers
Types
Bias: The influence of the interviewer on the interviewee which may affect the interviewees and cause differential responses among them
Variance: A measure of how different responses are between different interviewers
One important factor to be aware of when you conduct a survey during an outbreak investigation is interviewer error. Interviewer error is simply a deviation from the expected answer due to the effects of the individual interviewer. Interviewer error can be prevented with adequate interviewer training and standardization of survey instruments.
The two components of error are bias and variance. Bias is the influence of the interviewer on the interviewee. This influence may not even be intentional, it may be due to physical presence or other characteristics… or it could be due to subtle cues such as tone of voice or body language that affect the interviewees and cause them to answer differently. Variance is a measure of how different responses are between different interviewers. We will cover an example of interviewer bias and variance within the same outbreak investigation on the next slide.

21. Interviewer Error Example
Gonorrhea outbreak
Bias
Interviewers probe on the sexual history section more for non-whites than whites
Variance
A male interviewer may elicit different responses from a female respondent than a female interviewer
Let’s look at a hypothetical example of interviewer error in an outbreak of gonorrhea in a cluster of year olds. In interviews regarding gonorrhea exposure and infection, an interviewer asks probing questions or even prompts answers from interviewees who do not have a complete high school education, but doesn’t ask as many probing questions to college graduates. As you can imagine, this would lead to differential data quality by educational status and may hamper investigators’ ability to identify all potentially infected persons – especially if education level or association with a school or college is associated with gonorrhea exposure, infection, or both. Interviewer bias is often the result of incomplete or no interviewer training.
In the same gonorrhea outbreak, suppose we have both a male and female interviewer. The male interviewer may elicit different responses from a female respondent than a female interviewer. A female respondent may not feel comfortable telling a man about her sexual history. Interviewer variance occurs because different interviewers have different effects on respondents. Generally speaking, this is not a widespread phenomenon; in this example we might see that male interviewers affect only a very small number of female respondents.

22. Methods to Standardize Interviews
Standard question wording
Interviewer selection
Interviewer training
Standard interviewing procedures
Supervision of interviewers
The goal of standardizing interviews is to reduce error. There are methods we can employ to try to standardize the interview process. They are:
Standardization of question wording
Careful interviewer selection
Interviewer training, including standardization of interviewing procedures, and supervision of interviewers.
Let’s discuss the first two items on this list now, and then we will talk in more detail about interviewer training.

23. Question Wording Fully scripted
Every interviewer asks the same question in the same way using the same words
Means the same thing to every respondent
Let’s begin with standardizing the question wording. Questions on a questionnaire should be fully scripted, so that every interviewer asks each question in the exact same way, using the same words. Remember from our last presentation, if the questionnaire has been piloted, you should also have a question that has been crafted so that it means the same thing to every respondent.

24. Interviewer Selection: Telephone Interviews
Ability to read questions fluently
Clear and pleasant telephone voice
Respond quickly to respondent’s questions
Reliable
Selecting interviewers who have the skill and acumen to carry out a good interview is also a critical part of holding standardized interviews.
For telephone interviews specifically, all interviewers must be able to read questions fluently, they should possess a clear and pleasant telephone voice, they should be able to respond quickly to respondent’s questions without becoming flustered using the standard script provided, and they should be reliable so that you can trust them to carry out their task.

25. Interviewer Selection: Face-to-Face Interviewers
Logistical skills (reading maps)
Good interpersonal skills
Independent and reliable
Demographic characteristics may be important
Safety conscious
For face-to-face interviews, the interviewer must have some logistical skills, such as reading maps, in order to arrive at their correct destinations, and must be able to handle themselves if unexpected circumstances arise during or between interviews. Interviewers must also have good interpersonal skills, and must be independent and reliable.
In some circumstances, the demographic characteristics of the interviewer may be important. For example, in an investigation that involves sensitive issues such as sexually transmitted disease, both gender and the age of the interviewer may influence the way a respondent answers the questions.
To ensure interviewer safety, you may want to consider sending interviewers out in teams of two, and these teams must work well together. Remind interviewers that their safety is more important than conducting an interview.

26. Interviewer Training
Now let’s discuss interviewing training methods.

27. Interviewer Training is not Optional
Familiarize interviewers with the instrument
Training on intent of each question
Practice reading questions out loud
Provide interactive feedback
Practice interviews
Practice responding to questions or problems
Offer support documentation (manual)
Obviously, outbreak investigations require a rapid response but this does not mean that interviewer training is optional.
Even if interviewers receive a short training, some training must be done. Ideally, trainings should be interactive. Practice reading the questions out loud allows interviewers to become familiar with the survey instrument and can help in predicting problems with questions on the survey. Providing interactive feedback through these practice interviews can help each interviewer feel more confident before they begin working. In addition, some sort of support documentation, known as an interviewer manual, must be provided to all interviewers, and should include information about the instrument and any procedures they need to carry out.
You may want to consider scheduling a general interviewer training session or adding a short interviewing techniques module to another upcoming health department training. Having trained interviewers in advance of an outbreak investigation or disaster situation can save time and improve the quality of your data when the next ‘real life’ opportunity to conduct an interview presents itself.

28. Interviewer Training Elements
Purpose of survey
Respondent selection process
How to use data collection instrument
How to record/code responses
Administering questionnaire
Addressing participants’ questions
Methods for improving response rate
Tracking attempted and completed interviews
Confidentiality
There are several topics to cover in the interviewer training. They are:
The purpose of the survey;
The respondent selection process;
How to use the data collection instrument, which includes administering the questionnaire, and training on the intent and meaning of each question;
How to record or code responses;
Addressing respondents’ questions;
Methods for improving the response rate;
Tracking attempted or completed interviews, including the total number of calls or visits made and the number of times to make call-backs; and
Confidentiality.
We will discuss specifics about the respondent selection process, administering the questionnaire, and logistics in the following slides.

29. Respondent Selection
Provide proxy respondent rules for adults and children
Proxy response impacts:
Data quality
Sampling
When instructing interviewers about selecting a person in the household to interview, you must address the issue of proxy respondents. A proxy is someone that responds to the survey in lieu of the actual case.
Clearly, for children, you will have to speak to a parent or guardian, but you should instruct interviewers at what age children can respond for themselves. In some circumstances, a 12-year old may be able to answer interview questions, as long as a parent or guardian is present, but in other circumstances it may be appropriate for a proxy to answer for any case-patient that is of minor age. In addition, if the intended interviewee is not at home, no matter what their age, someone else in the household might volunteer to respond to the survey in their place. Rules about adult proxy responding must be established and communicated to the interviewer during the training process.
Proxy responding rules impact both data quality and sampling.

30. Questionnaire Administration
To establish legitimacy of the survey upon first contact, tell the respondent:
Who is calling
What is requested
Why the respondent should cooperate
How the respondent was chosen
One important piece of administering the questionnaire is securing the respondent’s cooperation. This may be more of an issue for controls, who are probably not familiar with the outbreak investigation. In order to establish legitimacy of the survey, the interviewer must tell the respondent who is calling, what is requested, why the respondent should cooperate , and how they were chosen.
Without an understanding of this preliminary information, a potential respondent may not be inclined to participate.

31. Train Interviewers on Logistics
Face-to-Face
Telephone
Reading maps
Getting to respondents’ homes
Reimbursement
Dress code
Scheduling revisits
Scheduling
Operation of equipment
Interviewers must also be trained or competent in some logistical details to perform effectively, such as reading maps, getting to respondents’ homes, and understanding reimbursement, dress code and scheduling callbacks procedures. For telephone interviewers, interviewers must be trained on how to operate the equipment.

32. Other Interviewer Training Considerations
Record some resolution to each question
Are missing responses due to skip patterns or errors?
Review interview after completion
Missing responses
Illegible responses
There are a few other considerations in training interviewers.
It is important to stress to interviewers that each question must have some response or resolution. For example, if all questions are not fully answered, it may be difficult to tell if a question is skipped due to a skip pattern or if the question was simply overlooked. This distinction becomes important in the analysis phase of the investigation.
Ideally, after the completion of an interview, the interviewer will review each completed interview to note any missing or illegible responses.

33. Standard Interviewing Procedures
Rules:
Read questions exactly as worded
Probe inadequate answers, if necessary
Record answers without interviewer discretion
Maintain rapport with respondents
Maintain an even pace
Let’s now consider some important interviewing procedures that will enhance your data collection efforts. All interviewers must follow some basic rules when conducting an interview. They must:
Read questions exactly as worded,
Probe inadequate answers, if necessary,
Record answers without their own discretion,
Maintain a rapport with respondents, and
Maintain an even pace throughout interviews

34. Read Questions Exactly
Read entire question before accepting an answer
Clarify questions if necessary
Use only standard definitions / clarification provided
Use the phrase:
“Whatever x means to you”, OR
“Whatever you think of as x.”
When asked to repeat only one of several response options, repeat ALL options given for a question
In reading the questions exactly as worded, an interviewer should read the entire question before accepting an answer. This may seem time consuming and unnecessary in some situations, but it is important to setting the pace of the interview and giving the respondent time to think about the question being asked.
The interviewer should also clarify questions if needed. Since it may be difficult to write a survey question that means the same thing to each respondent, clarification is necessary from time to time. But the clarification of a question may be problematic if the interviewer begins to interpret the question as s/he perceives it. Supporting documentation in the interviewer manual can facilitate standardized question clarification.
Here are a few ways to avoid having the interviewer interpret survey questions in order to provide clarification to respondents. Interviewers should use standard definitions provided to them, for example, in manual documentation. Making up definitions for unfamiliar words is not a good interviewing technique.
The respondent may ask what is meant by a subjective term or phrase in a question. If no standard definitions are available, the interviewer can use the phrase: “Whatever x means to you” or “Whatever you think of as x”. Again, the interviewer should avoid interpreting the question.
And finally, when asked to repeat one of several response options, it may be best to repeat all of them. This gives the respondent more time to ponder the question.

35. Probes
A probe is a standardized way to obtain additional information from a respondent.
Use probes when a respondent’s answer is unclear or irrelevant.
A common practice in interviewing is to probe a respondent for additional information. It is important to recognize that probing should be done in a standardized way so as to not influence the response. A probe is generally used when a respondent’s answer is unclear or irrelevant.

36. Example Responses Requiring Probes
Interviewer:
"In the past two weeks, have you been swimming in a public pool?”
Irrelevant response:
“I swam in a lake at a national park last month."
Unclear response:
“I stayed in a hotel with a pool when I was on vacation last week."
Let’s look at an example. During an outbreak investigation, the interviewer asks “In the past two weeks, have you been swimming in a public pool?" The respondent replies, “I swam in a lake at a national park last month." This is an irrelevant response. The question is asking about public pools in the past 2 weeks. A probe would be necessary here.
Another respondent replies, “I stayed in a hotel with a pool when I was on vacation last week." This is an unclear answer. The interviewer should not assume this means that the respondent actually swam in the pool without probing for further clarification.

37. Standard Probe Examples
Repeat the question
Retrieve receipts / calendars
What do you mean? How do you mean?
If respondent has narrowed down answer:
Which would be closer?
If you had to choose, which would you pick?
Often times, the best probe is simply to repeat the question; this is a neutral probe that an interviewer can consistently rely on.
An interviewer may ask the respondent to retrieve various items such as receipts from a restaurant or a calendar or date book. These items will help respondents better recall exact dates and food items eaten.
There are other neutral phrases you can use, such as:
What do you mean?
How do you mean?
And if the respondent has narrowed the answer down to a few choices, an interviewer could say -- Which would be closer? If you had to choose, which would you pick?

38. Recording Answers Do not direct respondent toward an answer (leading)
Do not assume that something said in passing is the correct answer
Do not skip questions, even if an “answer” was given earlier
Do not remind respondent of an earlier remark if an answer differs from what you expect
When an interviewer is recording an answer, s/he should avoid several temptations.
First, do not direct the respondent toward an answer. This is also called leading.
Also, do not assume that something a respondent said in passing is the answer the respondent wants to give. For example, say in one question you ask if the respondent has ever had a particular vaccination, and they say that yes, they had the vaccination last year. The next question asks how old they were when they had the vaccination. Do not assume that you can take their age and subtract one year, so that you do not have to ask the question about age of vaccination. Ask all questions exactly as written. Similarly, do not skip questions even if the answer was already given as part of an earlier response.
Finally, do not remind the respondent of an earlier remark if an answer differs from what you expected to hear. For example, if they tell you that they were 64 when they last received an influenza vaccination, do not say, “I thought you said you got that vaccination last year? Right now you are 67.” Simply record the answer the respondent gives.

39. Probing versus Leading
Example:
Interviewer: In the last 7 days, how many times did you eat prepared food at the dorm cafeteria? Would you say:
Not at all d. 3 times
Once e. More than 3 times
Twice
Respondent:
“Oh, gee, I didn’t go very often maybe a few times.”
Let’s look at another example of probing versus leading. The interviewer asks “In the last 7 days, how many times did you eat prepared food at the dorm cafeteria? Would you say: not at all, once, twice, 3 times, or more than 3 times.” The respondent replies “Oh gee, I didn’t go very often, maybe a few times.”

40. Probing versus Leading
Example:
Interviewer Probe (correct)
“Which would be closer: not at all, once, twice, 3 times, or more than 3 times?”
Interviewer Leading (incorrect)
“So, would you say twice, or 3 times?”
One way the interviewer could respond is to use a probe. S/he could say, “which would be closer: not at all, once, twice, 3 times or more than 3 times?” This probe reiterates every possible response category. It allows the respondent a bit more time to consider what s/he ate in the last 7 days.
In this situation, the interviewer may succumb to the temptation of inadvertently leading the respondent. The interviewer could respond, “So would you say twice, or three times?” This response is problematic. The interviewer cannot assume the respondent’s frame of reference for “a few times” is 2 or 3. By narrowing down the answers for the respondent, the interviewer is leading the respondent to a response.

41. Maintain Rapport
“Any line can be said a thousand ways.”
- BRFSS interviewer training
Interviewers can put respondents at ease by doing the following:
Read the questions in a friendly, natural manner
Speak at a moderate rate of speed
Sound interested
Strive to be objective and non-judgmental
Attitude and rapport are very important to emphasize in interviewer training. A line from the Behavioral Risk Factor Surveillance System interviewer training notes that any line can be said a thousand ways. Whether an interviewer is perceived as professional but approachable or cold and detached can make a big difference in the interview process.
Interviewers can put respondents at ease by:
Reading the questions in a friendly, natural manner,
Speaking at a moderate rate of speed,
Sounding interested, and
Striving to be objective and non-judgmental.

42. Feedback Helps Maintain Rapport
Feedback is a statement or action that indicates to the respondent that s/he is doing a good job
Give feedback only for acceptable performance - not “good" content
Examples of feedback:
“I see…”
“Thank you / Thanks”
“That is useful / helpful information”
“I want to make sure I have that right (REPEAT ANSWER)”
One tactic to maintain rapport with the respondent is to provide feedback.
Feedback is a statement or action that indicates to the respondent that s/he is doing a good job. Inexperienced interviewers may use feedback inappropriately, so it is important to keep these tips in mind:
Give feedback only for acceptable performance, not “good" content. For example, if the respondent is answering questions about smoking and tells the interviewer that he quit a few months ago, the interviewer may be tempted to provide a bit of encouragement. That is exactly what should be avoided.
Examples of correct feedback include:
I see…
Uh-huh
Thank you
That is useful information
I see, that is helpful to know
That is useful for our research
Let me get that down
I want to make sure I have that right (REPEAT ANSWER)
We have touched on this before, but I need to ask every question in the order that it appears in the questionnaire

43. Maintain an Even Pace
Pace refers to the rate of progression of the interview
Pace can vary by question type
Let the respondent set the pace
Pace refers to the rate of progression of the survey. In general, you want to maintain an even pace throughout the interview, and interviewers should let respondents set that pace. Older people may prefer a slower pace, while younger persons a faster one. If the respondent seems impatient, try to speed up the pace of the survey. Conversely, if the respondent is having trouble recalling answers, allow him / her more time to think.

44. Supervising Interviewers
Important to ensuring standardized interviews
Monitor, evaluate, and provide feedback to interviewers
Focus on the way interviewers handle the question-answer process (telephone interviews)
There is one final topic to cover today: supervising your trained interviewers.
Supervising interviewers may seem like a luxury of time in an outbreak investigation.
It is, however, important in ensuring standardization in interviews. As we know, standardization results in better data quality. Ideally, a supervisor would monitor, evaluate, and provide feedback to interviewers about the way the interviewers handle the question-answer process. This type of supervision only applies to telephone interviews.

45. Supervising Interviewers
Schedule interviewers
Number of interviewers needed
Time calls / visits will be made
Set up interview space
Track who has been called and who has not
Review data from completed interviews
Beyond monitoring interviewers, there are other tasks a supervisor must perform.
A supervisor can schedule interviewers -- this includes estimating both the number of interviewers needed and figuring out the dates/time of day to call or visit.
If necessary, a supervisor must set up the physical space in which interviews will be conducted.
A supervisor should also track who has been called and who has not. When numerous interviewers are involved, this may require more attention than you might think.
Beyond logistical concerns, supervisors should also review completed interviews. This is a good way to catch mistakes and correct them for the remainder of the interviews. Furthermore, the data collection phase of your research is the best time to catch errors and even conduct call-backs to respondents if necessary. You do not want to discover errors or missing data during the data analysis phase of your research!

46. Interviewer Training on Confidentiality
Research
Requires informed consent from human subjects
Outbreak investigations
Considered a public health emergency
Informed consent not required
The last topic we will address concerning interviewer training is confidentiality. Confidentiality is an important consideration in all the work we do – particularly within the context of the Health Insurance Portability and Accountability Act, or HIPAA, which protects individually identifiable personal health information. For research purposes, investigators are required to obtain informed consent from any human subjects participating in research. That is, investigators are required to clearly explain the research, what it entails, and the information that will be collected, and cannot perform any action including interviews without the individual giving their express consent. In addition, an internal review board, or IRB, from the sponsoring institution must review the study procedures and the information being collected
Outbreak investigations, however, are considered a public health emergency, with the purpose of identifying and controlling a health problem, informed consent is not required, nor are there other mandates that prevent personal health information from being used. However, this does not mean that investigators do not have to practice confidentiality with participant information.

47. Respondent Perspective
Confidentiality
Respondent Perspective
Opening statement of every interview should indicate that all information collected will be kept confidential.
Although outbreak investigations are exempt from filing Institutional Review Board paperwork and obtaining official “informed consent” for outbreak investigation or rapid needs assessment interviews, you should not overlook the issue of confidentiality from the respondent’s perspective.
All information collected from respondents must be kept confidential, and the opening statement of every interview should indicate that this will occur. This is important to help assure the respondent that the medical, personal, or demographic information they give you will be secure.
Confidentiality may be especially important in certain circumstances. For example, in 1982, there was a multi-state Salmonella outbreak linked to marijuana. Clearly, this would be a sensitive area where confidentiality concerns were of importance to the respondents.

48. Outbreak Investigation Perspective
Confidentiality
Outbreak Investigation Perspective
Do not discuss details about the outbreak
Provide only a brief description of the purpose of the survey at first contact
An interviewer should not give out details regarding the outbreak, except for providing a brief description of why you are calling at the beginning of an interview. It may be helpful to provide interviewers with a preset script of what can be disclosed about the outbreak to avoid any unnecessary disclosure.
If the respondent wants more information about the study, an interviewer should have a telephone number for him or her to call. This telephone number can be included in the supporting documentation in an interviewer’s manual.

49. Session Summary
Questionnaire design and interview methods are interrelated
The purpose of interviews in outbreak investigations is to collect data for case identification, risk factor identification, or hypothesis generation
Interview methods can be
Interviewer administered (face-to-face or telephone)
Self administered (mailed, ed, or Web-based)
Let’s review the main points of this session on interviewing techniques.
Questionnaire design and interview methods are interrelated in the overall process of an outbreak investigation.
The primary purpose of interviews in outbreak investigations is to collect data for case identification, risk factor identification, or hypothesis generation.
Interviews can be interviewer administered (face-to-face or telephone) or self administered (mailed, ed, or Web-based). There are advantages and disadvantages to employing either method.

50. Session Summary Interviewer error Sound interviewing procedures
Is a result of both bias and variance in the interview process
Can be prevented with interviewer training, interviewer manual, and standardization of the questionnaire
Sound interviewing procedures
Reading questions exactly
Probing inadequate answers
Recording answers without interviewer discretion
Maintaining rapport with respondents
Survey data collection error is a result of both bias and variance in the interview process. Interviewer error can be prevented with adequate interviewer training and the standardization of the questionnaire.
Sound interviewing procedures include: reading questions exactly as they are worded; probing inadequate answers; recording answers without interviewer discretion; and maintaining rapport with respondents. An interviewer manual is something you can also develop to provide interviewer support. Such documentation reduces error and enhances the quality of data collected.

51. References and Resources
Fowler, F. and Mangione, T. (1989). Standardized Survey Interviewing. Newbury Park: Sage Publications.
Gregg, M. (ed). (2008). Field Epidemiology. Oxford University Press.
Holstein, JA and Gubrium, JF. (1997). Active Interviewing. In Silverman, D. (Ed.) Qualitative Research: Theory, Method, and Practice. London: Sage Publications, pp
Rubin, HJ and Rubin, IS.  (1995). Interviews as Guided Conversations. Qualitative Interviewing: The Art of Hearing Data. Sage Publications, pp. 1-16,
Salant, P. and Dillman, D. (1994). How to Conduct Your Own Survey. John Wiley & Sons.

52. References and Resources
Scheuren, Franz. (1997). What Is a Survey? Alexandria, VA: Section on Survey Research Methods, American Statistical Association.
Stehr-Green, J.K. (2002). Gastroenteritis at a University in Texas: Case Study Instructor’s Guide. Atlanta, GA: U.S. Department of Health and Human Services, Public Health Service, Centers for Disease Control and Prevention.