Interviews are among the most challenging and rewarding forms of measurement. They require a personal sensitivity and adaptability as well as the ability to stay within the bounds of the designed protocol. Here, I describe the preparation you need to do for an interview study and the process of conducting the interview itself.
The Role of the Interviewer
The interviewer is really the "jack-of-all-trades" in survey research. The interviewer's role is complex and multifaceted. It includes the following tasks:
- Locate and enlist cooperation of respondents
The interviewer has to find the respondent. In door-to-door surveys, this means being able to locate specific addresses. Often, the interviewer has to work at the least desirable times (like immediately after dinner or on weekends) because that's when respondents are most readily available.
- Motivate respondents to do good job
If the interviewer does not take the work seriously, why would the respondent? The interviewer has to be motivated and has to be able to communicate that motivation to the respondent. Often, this means that the interviewer has to be convinced of the importance of the research.
- Clarify any confusion/concerns
Interviewers have to be able to think on their feet. Respondents may raise objections or concerns that were not anticipated. The interviewer has to be able to respond candidly and informatively.
- Observe quality of responses
Whether the interview is personal or over the phone, the interviewer is in the best position to judge the quality of the information that is being received. Even a verbatim transcript will not adequately convey how seriously the respondent took the task, or any gestures or body language that were evident.
- Conduct a good interview
Last, and certainly not least, the interviewer has to conduct a good interview! Every interview has a life of its own. Some respondents are motivated and attentive, others are distracted or disinterested. The interviewer also has good or bad days. Assuring a consistently high-quality interview is a challenge that requires constant effort.
Training the Interviewers
One of the most important aspects of any interview study is the training of the interviewers themselves. In many ways the interviewers are your measures, and the quality of the results is totally in their hands. Even in small studies involving only a single researcher-interviewer, it is important to organize in detail and rehearse the interviewing process before beginning the formal study.
Here are some of the major topics that should be included in interviewer training:
- Describe the entire study
Interviewers need to know more than simply how to conduct the interview itself. They should learn about the background for the study, previous work that has been done, and why the study is important.
- State who is sponsor of research
Interviewers need to know who they are working for. They -- and their respondents -- have a right to know not just what agency or company is conducting the research, but also, who is paying for the research.
- Teach enough about survey research
While you seldom have the time to teach a full course on survey research methods, the interviewers need to know enough that they respect the survey method and are motivated. Sometimes it may not be apparent why a question or set of questions was asked in a particular way. The interviewers will need to understand the rationale for how the instrument was constructed.
- Explain the sampling logic and process
Naive interviewers may not understand why sampling is so important. They may wonder why you go through all the difficulties of selecting the sample so carefully. You will have to explain that sampling is the basis for the conclusions that will be reached and for the degree to which your study will be useful.
- Explain interviewer bias
Interviewers need to know the many ways that they can inadvertently bias the results. And, they need to understand why it is important that they not bias the study. This is especially a problem when you are investigating political or moral issues on which people have strongly held convictions. While the interviewer may think they are doing good for society by slanting results in favor of what they believe, they need to recognize that doing so could jeopardize the entire study in the eyes of others.
- "Walk through" the interview
When you first introduce the interview, it's a good idea to walk through the entire protocol so the interviewers can get an idea of the various parts or phases and how they interrelate.
- Explain respondent selection procedures, including
- reading maps
It's astonishing how many adults don't know how to follow directions on a map. In personal interviews, the interviewer may need to locate respondents who are spread over a wide geographic area. And, they often have to navigate by night (respondents tend to be most available in evening hours) in neighborhoods they're not familiar with. Teaching basic map reading skills and confirming that the interviewers can follow maps is essential.
- identifying households
In many studies it is impossible in advance to say whether every sample household meets the sampling requirements for the study. In your study, you may want to interview only people who live in single family homes. It may be impossible to distinguish townhouses and apartment buildings in your sampling frame. The interviewer must know how to identify the appropriate target household.
- identify respondents
Just as with households, many studies require respondents who meet specific criteria. For instance, your study may require that you speak with a male head-of-household between the ages of 30 and 40 who has children under 18 living in the same household. It may be impossible to obtain statistics in advance to target such respondents. The interviewer may have to ask a series of filtering questions before determining whether the respondent meets the sampling needs.
- Rehearse interview
You should probably have several rehearsal sessions with the interviewer team. You might even videotape rehearsal interviews to discuss how the trainees responded in difficult situations. The interviewers should be very familiar with the entire interview before ever facing a respondent.
- Explain supervision
In most interview studies, the interviewers will work under the direction of a supervisor. In some contexts, the supervisor may be a faculty advisor; in others, they may be the "boss." In order to assure the quality of the responses, the supervisor may have to observe a subsample of interviews, listen in on phone interviews, or conduct follow-up assessments of interviews with the respondents. This can be very threatening to the interviewers. You need to develop an atmosphere where everyone on the research team -- interviewers and supervisors -- feel like they're working together towards a common end.
- Explain scheduling
The interviewers have to understand the demands being made on their schedules and why these are important to the study. In some studies it will be imperative to conduct the entire set of interviews within a certain time period. In most studies, it's important to have the interviewers available when it's convenient for the respondents, not necessarily the interviewer.
The Interviewer's Kit
It's important that interviewers have all of the materials they need to do a professional job. Usually, you will want to assemble an interviewer kit that can be easily carried and includes all of the important materials such as:
- a "professional-looking" 3-ring notebook (this might even have the logo of the company or organization conducting the interviews)
- sufficient copies of the survey instrument
- official identification (preferable a picture ID)
- a cover letter from the Principal Investigator or Sponsor
- a phone number the respondent can call to verify the interviewer's authenticity
So all the preparation is complete, the training done, the interviewers ready to proceed, their "kits" in hand. It's finally time to do an actual interview. Each interview is unique, like a small work of art (and sometimes the art may not be very good). Each interview has its own ebb and flow -- its own pace. To the outsider, an interview looks like a fairly standard, simple, prosaic effort. But to the interviewer, it can be filled with special nuances and interpretations that aren't often immediately apparent. Every interview includes some common components. There's the opening, where the interviewer gains entry and establishes the rapport and tone for what follows. There's the middle game, the heart of the process, that consists of the protocol of questions and the improvisations of the probe. And finally, there's the endgame, the wrap-up, where the interviewer and respondent establish a sense of closure. Whether it's a two-minute phone interview or a personal interview that spans hours, the interview is a bit of theater, a mini-drama that involves real lives in real time.
In many ways, the interviewer has the same initial problem that a salesperson has. You have to get the respondent's attention initially for a long enough period that you can sell them on the idea of participating in the study. Many of the remarks here assume an interview that is being conducted at a respondent's residence. But the analogies to other interview contexts should be straightforward.
- Gaining entry
The first thing the interviewer must do is gain entry. Several factors can enhance the prospects. Probably the most important factor is your initial appearance. The interviewer needs to dress professionally and in a manner that will be comfortable to the respondent. In some contexts a business suit and briefcase may be appropriate. In others, it may intimidate. The way the interviewer appears initially to the respondent has to communicate some simple messages -- that you're trustworthy, honest, and non-threatening. Cultivating a manner of professional confidence, the sense that the respondent has nothing to worry about because you know what you're doing -- is a difficult skill to teach and an indispensable skill for achieving initial entry.
- Doorstep technique
You're standing on the doorstep and someone has opened the door, even if only halfway. You need to smile. You need to be brief. State why you are there and suggest what you would like the respondent to do. Don't ask -- suggest what you want. Instead of saying "May I come in to do an interview?", you might try a more imperative approach like " I'd like to take a few minutes of your time to interview you for a very important study."
If you've gotten this far without having the door slammed in your face, chances are you will be able to get an interview. Without waiting for the respondent to ask questions, you should move to introducing yourself. You should have this part of the process memorized so you can deliver the essential information in 20-30 seconds at most. State your name and the name of the organization you represent. Show your identification badge and the letter that introduces you. You want to have as legitimate an appearance as possible. If you have a three-ring binder or clipboard with the logo of your organization, you should have it out and visible. You should assume that the respondent will be interested in participating in your important study -- assume that you will be doing an interview here.
- Explaining the study
At this point, you've been invited to come in (After all, you're standing there in the cold, holding an assortment of materials, clearly displaying your credentials, and offering the respondent the chance to participate in an interview -- to many respondents, it's a rare and exciting event. They hardly ever get asked their views about anything, and yet they know that important decisions are made all the time based on input from others.). Or, the respondent has continued to listen long enough that you need to move onto explaining the study. There are three rules to this critical explanation: 1) Keep it short; 2) Keep it short; and 3) Keep it short! The respondent doesn't have to or want to know all of the neat nuances of this study, how it came about, how you convinced your thesis committee to buy into it, and so on. You should have a one or two sentence description of the study memorized. No big words. No jargon. No detail. There will be more than enough time for that later (and you should bring some written materials you can leave at the end for that purpose). This is the "25 words or less" description. What you should spend some time on is assuring the respondent that you are interviewing them confidentially, and that their participation is voluntary.
Asking the Questions
You've gotten in. The respondent has asked you to sit down and make yourself comfortable. It may be that the respondent was in the middle of doing something when you arrived and you may need to allow them a few minutes to finish the phone call or send the kids off to do homework. Now, you're ready to begin the interview itself.
- Use questionnaire carefully, but informally
The questionnaire is your friend. It was developed with a lot of care and thoughtfulness. While you have to be ready to adapt to the needs of the setting, your first instinct should always be to trust the instrument that was designed. But you also need to establish a rapport with the respondent. If you have your face in the instrument and you read the questions, you'll appear unprofessional and disinterested. Even though you may be nervous, you need to recognize that your respondent is most likely even more nervous. If you memorize the first few questions, you can refer to the instrument only occasionally, using eye contact and a confident manner to set the tone for the interview and help the respondent get comfortable.
- Ask questions exactly as written
Sometimes an interviewer will think that they could improve on the tone of a question by altering a few words to make it simpler or more "friendly." DON'T. You should ask the questions as they are on the instrument. If you had a problem with a question, the time to raise it was during the training and rehearsals, not during the actual interview. It is important that the interview be as standardized as possible across respondents (this is true except in certain types of exploratory or interpretivist research where the explicit goal is to avoid any standardizing). You may think the change you made was inconsequential when, in fact, it may change the entire meaning of the question or response.
- Follow the order given
Once you know an interview well, you may see a respondent bring up a topic that you know will come up later in the interview. You may be tempted to jump to that section of the interview while you're on the topic. DON'T. You are more likely to lose your place. You may omit questions that build a foundation for later questions.
- Ask every question
Sometimes you'll be tempted to omit a question because you thought you already heard what the respondent will say. Don't assume that. For example, let's say you were conducting an interview with college age women about the topic of date rape. In an earlier question, the respondent mentioned that she knew of a woman on her dormitory floor who had been raped on a date within the past year. A few questions later, you are supposed to ask "Do you know of anyone personally who was raped on a date?" You figure you already know that the answer is yes, so you decide to skip the question. Instead, you might say something like "I know you may have already mentioned this, but do you know of anyone personally who was raped on a date?" At this point, the respondent may say something like "Well, in addition to the woman who lived down the hall in my dorm, I know of a friend from high school who experienced date rape." If you hadn't asked the question, you would never have discovered this detail.
- Don't finish sentences
I don't know about you, but I'm one of those people who just hates to be left hanging. I like to keep a conversation moving. Once I know where a sentence seems to be heading, I'm aching to get to the next sentence. I finish people's sentences all the time. If you're like me, you should practice the art of patience (and silence) before doing any interviewing. As you'll see below, silence is one of the most effective devices for encouraging a respondent to talk. If you finish their sentence for them, you imply that what they had to say is transparent or obvious, or that you don't want to give them the time to express themselves in their own language.
Obtaining Adequate Responses - The Probe
OK, you've asked a question. The respondent gives a brief, cursory answer. How do you elicit a more thoughtful, thorough response? You probe.
- Silent probe
The most effective way to encourage someone to elaborate is to do nothing at all - just pause and wait. This is referred to as the "silent" probe. It works (at least in certain cultures) because the respondent is uncomfortable with pauses or silence. It suggests to the respondent that you are waiting, listening for what they will say next.
- Overt encouragement
At times, you can encourage the respondent directly. Try to do so in a way that does not imply approval or disapproval of what they said (that could bias their subsequent results). Overt encouragement could be as simple as saying "Uh-huh" or "OK" after the respondent completes a thought.
You can encourage more information by asking for elaboration. For instance, it is appropriate to ask questions like "Would you like to elaborate on that?" or "Is there anything else you would like to add?"
- Ask for clarification
Sometimes, you can elicit greater detail by asking the respondent to clarify something that was said earlier. You might say, "A minute ago you were talking about the experience you had in high school. Could you tell me more about that?"
This is the old psychotherapist trick. You say something without really saying anything new. For instance, the respondent just described a traumatic experience they had in childhood. You might say "What I'm hearing you say is that you found that experience very traumatic." Then, you should pause. The respondent is likely to say something like "Well, yes, and it affected the rest of my family as well. In fact, my younger sister..."
Recording the Response
Although we have the capability to record a respondent in audio and/or video, most interview methodologists don't think it's a good idea. Respondents are often uncomfortable when they know their remarks will be recorded word-for-word. They may strain to only say things in a socially acceptable way. Although you would get a more detailed and accurate record, it is likely to be distorted by the very process of obtaining it. This may be more of a problem in some situations than in others. It is increasingly common to be told that your conversation may be recorded during a phone interview. And most focus group methodologies use unobtrusive recording equipment to capture what's being said. But, in general, personal interviews are still best when recorded by the interviewer using pen and paper. Here, I assume the paper-and-pencil approach.
- Record responses immediately
The interviewer should record responses as they are being stated. This conveys the idea that you are interested enough in what the respondent is saying to write it down. You don't have to write down every single word -- you're not taking stenography. But you may want to record certain key phrases or quotes verbatim. You need to develop a system for distinguishing what the respondent says verbatim from what you are characterizing (how about quotations, for instance!).
- Include all probes
You need to indicate every single probe that you use. Develop a shorthand for different standard probes. Use a clear form for writing them in (e.g., place probes in the left margin).
- Use abbreviations where possible
Abbreviations will help you to capture more of the discussion. Develop a standardized system (e.g., R=respondent; DK=don't know). If you create an abbreviation on the fly, have a way of indicating its origin. For instance, if you decide to abbreviate Spouse with an 'S', you might make a notation in the right margin saying "S=Spouse."
Concluding the Interview
When you've gone through the entire interview, you need to bring the interview to closure. Some important things to remember:
- Thank the respondent
Don't forget to do this. Even if the respondent was troublesome or uninformative, it is important for you to be polite and thank them for their time.
- Tell them when you expect to send results
I hate it when people conduct interviews and then don't send results and summaries to the people who they get the information from. You owe it to your respondent to show them what you learned. Now, they may not want your entire 300-page dissertation. It's common practice to prepare a short, readable, jargon-free summary of interviews that you can send to the respondents.
- Don't be brusque or hasty
Allow for a few minutes of winding down conversation. The respondent may want to know a little bit about you or how much you like doing this kind of work. They may be interested in how the results will be used. Use these kinds of interests as a way to wrap up the conversation. As you're putting away your materials and packing up to go, engage the respondent. You don't want the respondent to feel as though you completed the interview and then rushed out on them -- they may wonder what they said that was wrong. On the other hand, you have to be careful here. Some respondents may want to keep on talking long after the interview is over. You have to find a way to politely cut off the conversation and make your exit.
- Immediately after leaving -- write down any notes about how the interview went
Sometimes you will have observations about the interview that you didn't want to write down while you were with the respondent. You may have noticed them get upset at a question, or you may have detected hostility in a response. Immediately after the interview you should go over your notes and make any other comments and observations -- but be sure to distinguish these from the notes made during the interview (you might use a different color pen, for instance).
Copyright ©2006, William M.K. Trochim, All Rights Reserved
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Last Revised: 10/20/2006