Final october interviewing_techniques

139
Public Health Information Network (PHIN) Series II Outbreak Investigation Methods: From Mystery to Mastery

Transcript of Final october interviewing_techniques

Page 1: Final october interviewing_techniques

Public Health Information Network (PHIN)

Series II

Outbreak Investigation Methods:

From Mystery to Mastery

Page 2: Final october interviewing_techniques
Page 3: Final october interviewing_techniques

Access Series Files Online http://www.vdh.virginia.gov/EPR/Training.asp

Session slides

Session activities (when applicable)

Session evaluation forms

Speaker biographies

Alternate Web site: http://www.sph.unc.edu/nccphp/phtin/index.htm

Page 4: Final october interviewing_techniques

Site Sign-in Sheet

Please submit your site sign-in sheet andsession evaluation forms to:

Suzi SilversteinDirector, Education and Training

Emergency Preparedness & Response Programs

FAX: (804) 225 - 3888

Page 5: Final october interviewing_techniques

Series IISession V

“Interviewing Techniques”

Page 6: Final october interviewing_techniques

Series II Sessions

Title Date

“Recognizing an Outbreak” June 2

“Risk Communication” July 7

“Study Design” August 4

“Designing Questionnaires” September 1

“Interviewing Techniques” October 6

“Data Analysis” November 3

“Writing and Reviewing Epidemiological Literature”

December 1

Page 7: Final october interviewing_techniques

CDCOutbreak Management System

Software Support: National Center for Public Health [email protected] / (800) 532-9929, option 6

Page 8: Final october interviewing_techniques

OMS Applications

• Track demographics, case investigations, and exposure contact relationships for persons, animals, events, travel events, vehicles, objects, organizations, other organisms, and locations.

• Create household, social, or occupational relationships among records

• Run OMS on desktops or laptops [CAPI]

Page 9: Final october interviewing_techniques

OMS User Interface

Source: http://www.cdc.gov/phin/software-solutions/oms/index.html

Page 10: Final october interviewing_techniques

OMS User Interface

Source: http://www.cdc.gov/phin/software-solutions/oms/index.html

Page 11: Final october interviewing_techniques

OMS in Virginia

Contact:

Michael A. Coletta, MPHBioterrorism Surveillance CoordinatorDivision of Surveillance and InvestigationOffice of Epidemiology Telephone: (804) 864-8099Email: [email protected]

Page 12: Final october interviewing_techniques

Today’s Presenters

Aaron Wendelboe, MSPHDoctoral Candidate and Graduate Research Assistant,NC Center for Public Health Preparedness

Erin Rothney, MPHResearch Associate,NC Center for Public Health Preparedness

Page 13: Final october interviewing_techniques

“Interviewing Techniques” Learning Objectives

Upon completion of this session, you will:

• Recognize the interrelatedness of interview techniques and questionnaire design

• Understand key survey research terms• Understand the advantages and

disadvantages of face-to-face, telephone, and computer assisted interview methods

Page 14: Final october interviewing_techniques

Learning Objectives (cont’d.)

• Understand the advantages and disadvantages of mail and Web-based survey implementation

• Know what to address in interviewer training

• Recognize good interview techniques

• Understand confidentiality concerns from the perspectives of both the respondent and the outbreak investigator

Page 15: Final october interviewing_techniques

Lecturer

Aaron Wendelboe, MSPHDoctoral Candidate and

Graduate Research Assistant,NC Center for Public Health Preparedness

Page 16: Final october interviewing_techniques

Basic Steps of an Outbreak Investigation

1. Verify the diagnosis and confirm the outbreak

2. Define a case and conduct case finding

3. Tabulate and orient data: time, place, person

4. Take immediate control measures

5. Formulate and test hypothesis

6. Plan and execute additional studies

7. Implement and evaluate control measures

8. Communicate findings

Page 17: Final october interviewing_techniques

Interviewing Techniques

Introduction

Page 18: Final october interviewing_techniques

Introduction

• The role of interviews in outbreak investigations

• Types of interviewing methods

• Interrelatedness of interview method and questionnaire design

• Key survey research concepts– Sampling– Response rates

Page 19: Final october interviewing_techniques

Role of Interviews in Outbreak Investigations

Primary purpose: data collection

• Case identification

• Risk factor identification

• Hypothesis generation

Page 20: Final october interviewing_techniques

Interviewing Methods

1. Interviewer Administered– Face-to-face– Telephone

2. Self Administered– Mail-out– Email– Web-based

3. Combination of 1 and 2

Page 21: Final october interviewing_techniques

Questionnaire Design

Interview Method Influenced by:

• Length and format of questionnaire

• Question types used in a survey

• Cost considerations for survey implementation

Page 22: Final october interviewing_techniques

Sampling

Page 23: Final october interviewing_techniques

Sampling

Sampling is the systematic selection of a portion of the larger source population. A sample should be representative of the larger source population.

Page 24: Final october interviewing_techniques

Sampling

Source Pop: Students (12,000)

Sampled pop (150 students)

Page 25: Final october interviewing_techniques

Sampling

Why Sample?

Because it is more efficient – saves time and money!

Page 26: Final october interviewing_techniques

Sampling

Sample size

Is the purpose of the study to determine the source of the outbreak? – A small number of cases and controls can reveal risk

factors for infection.

Is the purpose of the study to determine the number of persons who become sick over a specific period of time [attack rate]?– A cohort study would require a larger sample.

Page 27: Final october interviewing_techniques

Sampling

Types of Sampling

Simple Random Sample (SRS) Randomly select persons to participate in study. There are many variations of SRS.

Convenience SampleChoose those individuals who are easily accessible.

Page 28: Final october interviewing_techniques

Sampling

Problems with Convenience Sampling

• Based on subjective judgment

• Cases may or may not be representative of the total population

• May lead to biased results

Page 29: Final october interviewing_techniques

Sampling

Additional Resources:

http://www.sph.unc.edu/nccphp/training/all_trainings/at_sampl.htm

1. “Sampling Case Studies”

2. “Survey Sampling: Precision, Sample Size, and Conducting a Survey”

3. “Survey Sampling Terminology and Methods”

Page 30: Final october interviewing_techniques

Response Rates

Page 31: Final october interviewing_techniques

Response Rates

Response rates measure the percentage of your sample that has participated in your survey.

Example:Using the campus directory, you email a survey to a random sample of 100 freshmen. 40 of those students complete the survey and return it electronically. Your response rate is 40%.

Page 32: Final october interviewing_techniques

Response Rates

High response rates ensure that survey data are representative of the source population, and that results will be valid.

Page 33: Final october interviewing_techniques

Response Rates

Types of Non-response

• Non-contact: No one at home

• Refusal to participate

• Inability to participate (due to language barrier or physical or mental condition)

Page 34: Final october interviewing_techniques

Response Rates

What is an average response rate?

Page 35: Final october interviewing_techniques

Response Rates

Determining Response Rates

Refer to the American Association of Public Opinion Research website: www.aapor.org

– Link to the document titled, “Standard definitions” from the home page.

Page 36: Final october interviewing_techniques

Interviewer AdministeredData Collection Considerations

Page 37: Final october interviewing_techniques

Interviewer Administered Data Collection

• Advantages and disadvantages of face-to-face interviews

• Advantages and disadvantages of telephone interviews

• Advantages and disadvantages of Computer assisted interviews

Page 38: Final october interviewing_techniques

Face-to-Face Interview

Advantages:

• Higher response rate

• Longer survey instrument

• Can have more complex skip patterns

• More accurate recording of responses– Less item non-response

• Appropriate for hard to reach populations (e.g., illiterate, institutionalized)

Page 39: Final october interviewing_techniques

Face-to-Face Interview

Disadvantages:

• Costly

• Potential for interviewer error

• Less anonymous than self-administered

– Potential for dishonesty

Page 40: Final october interviewing_techniques

Telephone Interview

Advantages:

• Less costly than face-to-face

• Higher response rates than mailed

• Quicker access to participants

• Supervision of interviewers feasible

• Can collect more sensitive information

• Survey design can be more efficient

Page 41: Final october interviewing_techniques

Telephone Interview

Disadvantages:

• Lower response rates than face-to-face

• Shorter questionnaires used

• Unable to capture important visual information (e.g., rash, working conditions)

• Under-coverage (e.g., population without phones)– 2.1% of total population in Virginia

Page 42: Final october interviewing_techniques

Computer Assisted Interviewing (CAI)

• CATI – Telephone

• CAPI – Personal

• ACASI – Audio

Page 43: Final october interviewing_techniques

CAPI Example:NC PHRST Teams

NC PHRST Team public health professionals use PDAs* for rapid needs assessment face-to-face interviews.

* PDA: Personal Digital Assistant, also sometimes called

hand-held computers, palmtops, and pocket computers

Page 44: Final october interviewing_techniques

EPI InfoGIS

Field Team 1 Field Team 2 Field Team 3Field Team 4 Field Team 5

Field data collection using IPAQ Pocket PCs equipped with GPS, GIS software and data collection forms.

Wireless: WIFI 802.11 or Bluetooth

Field Data Collection

Page 45: Final october interviewing_techniques
Page 46: Final october interviewing_techniques
Page 47: Final october interviewing_techniques

Pros:• Inexpensive• No special skills required for

data recording

Cons:• Requires double data-entry

– Greater risk of data errors• Clipboard and paper more

cumbersome in the field

Pros:• Eliminates double data entry• Provides routing and direction-

finding for field teams• Improved randomization

through GIS• Ability to quickly analyze and

map data

Cons:• Technology is expensive• Learning curve / required

training for data entry• Small screen size requires

scrolling through many questionnaire pages

Page 48: Final october interviewing_techniques

For More Information. . .

Steven Ramsey, RS

Team Leader / Industrial Hygienist

PHRST-5

Guilford County Health Department, NC

(336) -641-8192

Page 49: Final october interviewing_techniques

Self AdministeredData Collection Considerations

Page 50: Final october interviewing_techniques

Self-administeredData Collection

• Advantages and disadvantages of

mailed questionnaires

• Advantages and disadvantages of

Web-based questionnaires

Page 51: Final october interviewing_techniques

Mailed Questionnaire

Advantages:• More anonymous

• May collect more honest responses

• No interviewer error

• Less expensive

• Respondent has more time to think about question

Page 52: Final october interviewing_techniques

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

Page 53: Final october interviewing_techniques

Web-based Questionnaire

Advantages:

• Among some populations, most people may have access to the Web / email

• Inexpensive and fast

• No data entry required– Improves data quality

• Many vendors send data in a variety of formats

Page 54: Final october interviewing_techniques

Web-based Questionnaire

Disadvantages:• Mandatory access to and experience with

Internet• Potential connection speed and hardware /

software capacity limitations• Potential for multiple responses from one

individual• Potential for responses from non-sampled

respondents• Need email address list to contact sample

Page 55: Final october interviewing_techniques

Web-based QuestionnaireExample: Dartmouth University: 698 (13.8%) of 5060 students had conjunctivitis in spring 2002

• To identify risk factors...

– web-based questionnaire set up

– E-mail sent to 3682 undergraduates

– No data entry - rapid analysis

• 1832 responded (50% response rate)

-- Source: An outbreak of conjunctivitis due to atypical Streptococcuspneumoniae. N Engl J Med. 2003;348 (12):1112-21.

Page 56: Final october interviewing_techniques

Web-based Questionnaire

For a list of vendors that provide Web-based survey tools, please visit:

http://www.surveymonkey.com/Pricing.asp

Page 57: Final october interviewing_techniques

Question and Answer Opportunity

Page 58: Final october interviewing_techniques

5 minute break

Page 59: Final october interviewing_techniques

Standardizing Interviews

Page 60: Final october interviewing_techniques

Standardizing Interviews

• The goal of standardization is to help minimize error, thereby yielding better data quality

• Minimizing interviewer error is done through making surveys more standard or consistent

Page 61: Final october interviewing_techniques

Error

Interviewer Error:

Deviation from expected answer due to the effects of interviewers.

Page 62: Final october interviewing_techniques

Interviewer ErrorExample: Gonorrhea outbreak

Bias

Interviewers probe on the sexual history section more among non-whites than whites

Variance

A male interviewer may elicit different responses from a female respondent than a female interviewer.

Page 63: Final october interviewing_techniques

Error

Additional Resource

Schwarz, N., Groves, R., and Schuman, H., “Survey Methods” Chapter 4 in Gilbert, D. et al (Eds) (1998). The Handbook of Social Psychology. Boston: McGraw-Hill; pp 143 – 179.

Page 64: Final october interviewing_techniques

Standardizing Interviews

Contributing Factors:

1. Question wording

2. Interviewer selection

3. Interviewer training

4. Interviewing procedures

5. Supervising interviewers

Page 65: Final october interviewing_techniques

1. Question Wording

Page 66: Final october interviewing_techniques

Question Wording

Criteria for Standardized Interview Questions

• Must be fully scripted

• Must mean the same thing to every respondent

Page 67: Final october interviewing_techniques

2. Interviewer Selection

Page 68: Final october interviewing_techniques

Interviewer Selection

Criteria for Telephone Interviewer Selection

• Ability to read questions fluently

• Clear and pleasant telephone voice

• Responds quickly to respondent’s questions

• Reliability

Page 69: Final october interviewing_techniques

Criteria for Face-to-FaceInterviewer Selection

• Logistical skills (reading maps)

• Good interpersonal skills

• Independent workers

• Reliability

• In certain circumstances, parallel demographic characteristics among interviewers and interviewees

Page 70: Final october interviewing_techniques

3. Interviewer Training

Page 71: Final october interviewing_techniques

Interviewer Training

• Training is NOT optional!

• Trainings must be interactive

• Interviewers must practice reading questions out loud

• Provide support documentation (manual)

Page 72: Final october interviewing_techniques

Interviewer TrainingElements

Purpose of survey How to use data collection instrument Respondent selection process Intent and meaning of each question How to record/code responses Administering questionnaire Addressing participants’ questions Methods for improving response rate Tracking calls / completed surveys / call-

backs Confidentiality

Page 73: Final october interviewing_techniques

Interviewer Training

Respondent Selection Process

Provide proxy respondent rules for adults and children because proxy response impacts:– Data quality– Sampling

Page 74: Final october interviewing_techniques

Interviewer Training

Questionnaire Administration

To establish legitimacy of the survey upon first contact, tell the respondent:

Who is callingWhat is requestedWhy respondent should cooperateHow respondent was chosen

Page 75: Final october interviewing_techniques

Interviewer TrainingLogistics

Face-to-Face

• Reading maps • Getting to

respondents’ homes• Reimbursement• Dress code• Scheduling callbacks

Telephone

• Operation of equipment• Operation of CATI

software (if applicable)

Page 76: Final october interviewing_techniques

Interviewer Training

Other Considerations

• Record some resolution to each question– Are missing responses due to skip patterns or

errors?

• Review interview after completion– Missing responses– Illegible responses

Page 77: Final october interviewing_techniques

Interviewer Training

Interviewer Manual

An interviewer manual serves as a reference to interviewers during interviews and as survey documentation.

Page 78: Final october interviewing_techniques

Interviewer Training

Suggested Interviewer Manual Contents

• Background information

• Fieldwork

• Interviewing techniques

• Survey instrument terms and definitions

Page 79: Final october interviewing_techniques

Interviewer Training Program Example

Behavioral Risk Factor Surveillance System (BRFSS)

Page 80: Final october interviewing_techniques

BRFSS Interviewer Training

On-line training covers:

• Why BRFSS data are important, how data are used

• Interviewer responsibilities

• Nuts and bolts of the interviewing process

• Interviewing techniques

Page 81: Final october interviewing_techniques

BRFSS Interviewer Training

On-line interviewer training available at:

http://apps.nccd.cdc.gov/BRFSS_Training_Int/overview.asp

General information about BRFSS: http://www.cdc.gov/brfss/

Page 82: Final october interviewing_techniques

4. Interviewing Procedures

Page 83: Final october interviewing_techniques

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

Page 84: Final october interviewing_techniques

Interviewing Procedures

Read questions exactly

• Read entire question before accepting an answer

• Clarify questions if necessary

Page 85: Final october interviewing_techniques

Interviewing Procedures

Read questions exactly • 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

Page 86: Final october interviewing_techniques

Interviewing Procedures

Probe

A probe is a standardized way to obtain additional information from a respondent.

Use probes when a respondent’s answer is unclear or irrelevant.

Page 87: Final october interviewing_techniques

ProbeExamples of responses requiring a probe:

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."

Page 88: Final october interviewing_techniques

Interviewing Procedures

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?

Page 89: Final october interviewing_techniques

Interviewing Procedures

Recording Answers

• Do not direct respondent toward an answer (leading)

• Do not assume that an “answer” received in passing is correct

• Do not skip questions, even if “answer” was given earlier

• Do not remind respondent of earlier remark if answer differs from what you expect

Page 90: Final october interviewing_techniques

Probing versus LeadingExample:

Interviewer: In the last 7 days, how many times did you eat prepared food at the dorm cafeteria? Would you say:

a. None d. 3 times

b. Once e. More than 3 times

c. Twice

Respondent:

“Oh, gee, I didn’t go very often . . . maybe a few times.”

Page 91: Final october interviewing_techniques

Probing versus LeadingExample:

Interviewer Probe (correct)

“Which would be closer: none, once, twice, 3 times, or more than 3 times?”

Interviewer Leading (incorrect)

a. “So, would you say twice, or three times?”

b. “Do you mean twice, or three times?”

Page 92: Final october interviewing_techniques

Interviewing Procedures

Maintain Rapport

An interviewer should be: • Nonjudgmental

• Noncommittal

• Objective

Page 93: Final october interviewing_techniques

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 for a low-pitched voice

Page 94: Final october interviewing_techniques

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.

– Give short feedback phrases for short responses, longer feedback for longer responses.

– Specific study information and interviewer task-related comments can serve as feedback.

– Telephone interviewers should give feedback for acceptable respondent performance 30-50% of the time.

Page 95: Final october interviewing_techniques

Feedback Examples

• “I see…”• “Uh-huh”• “Thank you / Thanks”• “That is useful / helpful 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”

Page 96: Final october interviewing_techniques

Interviewing Procedures

Maintain Even Pace

• Pace refers to the rate of progression of the interview.

• Pace can vary by question type.

• Let the respondent set the pace.

Page 97: Final october interviewing_techniques

Question and Answer Opportunity

Page 98: Final october interviewing_techniques

Activity: Correct Interview ProceduresProbing vs. Leading vs. Feedback

Completion time: 5 minutes

Page 99: Final october interviewing_techniques

ActivityInterviewer: “Are you still experiencing Diarrhea?”Respondent 1: “I’m not sure”

Respondent 2: “I definitely had diarrhea last Tuesday”

Respondent 3: “Yes”

Activity Instructions:How should the interviewer respond to these 3 answers? Provide an example of either a clarification, probe, or feedback that the interviewer could use. Try to think of one correct use of each technique.

Page 100: Final october interviewing_techniques

Activity

Suggested Answer

Respondent 1: “I’m not sure”

Try a clarification:

“For the purposes of this survey, we consider diarrhea to be 3 or more loose bowel movements in a 24 hour period.”

Page 101: Final october interviewing_techniques

Activity

Suggested Answer

Respondent 2: “I definitely had diarrhea last Tuesday”

Try a Probe:“OK, but are you still experiencing diarrhea?”

Page 102: Final october interviewing_techniques

Activity

Suggested Answer

Respondent 3: “Yes”

Good Feedback: “I see”

Bad Feedback: “Are you sure?” (leading)

Page 103: Final october interviewing_techniques

5. Supervising Interviewers

Page 104: Final october interviewing_techniques

Supervising Interviewers

Monitoring, evaluation, and feedback given to interviewers should focus on the way interviewers handle the question-answer process.

Page 105: Final october interviewing_techniques

Other Supervision Tasks

• Scheduling interviewers– Number of interviewers needed– Time calls / visits will be made

• Setting up interview space

• Tracking who has been called and who has not

• Reviewing data from completed interviews

Page 106: Final october interviewing_techniques

Confidentiality

Page 107: Final october interviewing_techniques

Confidentiality

Human Subjects & Informed Consent

Outbreak investigations are considered a public health emergency, with the purpose of identifying and controlling a health problem. Informed consent or Institutional Review Board (IRB) clearance are not required.

Page 108: Final october interviewing_techniques

Confidentiality

Human Subjects & Informed Consent

If further analysis of outbreak investigation data is conducted for the purpose of research, IRB approval should be obtained.

Page 109: Final october interviewing_techniques

Confidentiality

Respondent Perspective

Opening statement of every interview should indicate that all information collected will be kept confidential.

Page 110: Final october interviewing_techniques

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

Page 111: Final october interviewing_techniques

Question and Answer Opportunity

Page 112: Final october interviewing_techniques

5 minute break

Page 113: Final october interviewing_techniques

Guest Lecturer

Erin Rothney, MPH

Research Associate

NC Center for Public Health Preparedness

Page 114: Final october interviewing_techniques

Overview

• Provide real-life examples of situations where you will use interviewing techniques

– Face-to-face interviewing

– Telephone interviewing

• Discuss advantages and disadvantages

• Compare interviewing methods

Page 115: Final october interviewing_techniques

Face-to-face Interviews

Page 116: Final october interviewing_techniques

Community Assessments

• Identify the needs and strengths of a particular community from several stakeholder perspectives

• Include interviewing community members and observing the environmental and individual characteristics and community infrastructure

• Similar to rapid needs assessments, but completed within a longer time frame

Page 117: Final october interviewing_techniques

Durham, NCCommunity Assessment

• Fall 2002 - Spring 2003

• Bragtown Neighborhood, Durham, NC

• 5 person team

• Interviewed residents and other stakeholders in Bragtown

• 4 page survey, 60 minutes in length

Page 118: Final october interviewing_techniques

Durham, NCCommunity Assessment

Tasks:

• Questionnaire design• Interviewer training• Interviewing• Facilitating focus groups• Analyzing data• Presenting data to the community

Page 119: Final october interviewing_techniques

Survey InstrumentQuestion Examples:

Life in the Community• What do people in Bragtown do for recreation?• What types of religion are practiced in Bragtown?• What do people in Bragtown do for a living?• What political or government organizations exist in Bragtown?• What different cultural and ethnic groups live in Bragtown?• How do these different groups interact? Do they get along?

Community Assets• What do you like about Bragtown?• What are some organizations within your community that

positively affect you or your community? – Probe: What about political groups, environmental groups, church

groups?• Who are the individuals within your community that you feel are

positive leaders or role models? – Probe: Any others?

Page 120: Final october interviewing_techniques

Interviewer Training

• Active listening skills

• Showing empathy

• Using probes

• Practice interviewing, not just reading questions

Page 121: Final october interviewing_techniques

Face-to-face InterviewsChallenges

Hard to find people at home

People may not want to invite a stranger into their home

Costly and time-intensive method of interviewing

Solutions

Schedule time ahead by phone or stop by and schedule more convenient time

Use the skills you learned in interviewer training to gain trust

Have someone on staff train others on interviewing techniques; carpool; set time limits

Page 122: Final october interviewing_techniques

Lessons Learned

1. Study community demographics and characteristics before you interview

2. Train interviewers before an immediate need

3. People like to tell you their stories- could lead to relevant information

Page 123: Final october interviewing_techniques

Telephone Interviews2004 E. coli Outbreak Investigation

Page 124: Final october interviewing_techniques

E. coli Outbreak Investigation Telephone Interviews

• Illness onset October - November 2004

• Geographically dispersed cases in multiple states

• Case-control study

• Train-the-trainer, interviewer

Page 125: Final october interviewing_techniques

E. coli Outbreak InvestigationTelephone Interviews

• Between 3 and 6 interviewers

• Calls made between 3 p.m. and 8 p.m.

• Quality control with one central interviewing location

• News coverage piqued people’s interest in the outbreak investigation

Page 126: Final october interviewing_techniques

Lessons Learned

1. Practice reading through the questions and conducting an interview

2. The media can be your friend

3. Use an introductory script to relate the purpose of the phone call to the individual quickly

– Identify and legitimize the interviewer– State reasons for conducting the survey– Assure that responses will be confidential

Page 127: Final october interviewing_techniques

Summary

[Face-to-face]Community Assessment

– Establish rapport

– Identify people in a small geographic area

– Assess the environment of the area

[Telephone]Outbreak Investigation

– News coverage helped in recruiting people to participate

– Widely distributed sample

– We had the phone numbers of all the people who pre-bought tickets

Page 128: Final october interviewing_techniques

Question and Answer Opportunity

Page 129: Final october interviewing_techniques

Session Summary

Page 130: Final october interviewing_techniques

Session Summary

• 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.

Page 131: Final october interviewing_techniques

Session Summary

• Interview methods can be interviewer administered (face-to-face or telephone) or self administered (mailed, emailed, or Web-based). There are advantages and disadvantages to employing either method.

• Sampling is the systematic selection of a representative portion of the larger source population to be interviewed. If the purpose of your study is to determine the point source of infection, you may be able to interview a smaller sample; if the purpose of your study is to calculate an attack rate, you may need to interview a larger sample.

Page 132: Final october interviewing_techniques

Session Summary

• Survey response rates measure the percentage of your sample that has participated in your survey. Average response rates vary from as little as 56% for mailed surveys to 75% for face-to-face surveys.

• Non-response to surveys can be a result of no one being home, refusal to participate, or individual inability to participate (e.g., because of a language barrier or physical or mental condition).

Page 133: Final october interviewing_techniques

Session Summary

• 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 survey instruments.

Page 134: Final october interviewing_techniques

Session Summary

• Develop and distribute an interviewer manual to provide interviewer support. Such documentation reduces error and enhances the quality of data collected.

• Sound interviewing procedures include: reading questions exactly as they are worded; probing inadequate answers; recording answers without interviewer discretion; and maintaining rapport with respondents.

Page 135: Final october interviewing_techniques

Next Session November 3rd1:00 p.m. – 3:00 p.m.

Topic: “Analyzing Data”

Page 136: Final october interviewing_techniques

References and Resources

1. American Statistical Association (1997). What Is a Survey? More About Mail Surveys. Alexandria, VA: Section on Survey Research Methods, American Statistical Association.

2. American Statistical Association (1997). What Is a Survey? How to Collect Survey Data. Alexandria, VA: Section on Survey Research Methods, American Statistical Association.

3. Centers for Disease Control and Prevention (2005). Outbreak Management System Demonstration Web site. http://www.cdc.gov/phin/software-solutions/oms/index.html.

Page 137: Final october interviewing_techniques

References and Resources

4. Fowler, F. and Mangione, T. (1990). Standardizing Survey Interviewing. Newbury Park: Sage Publications.

5. Gregg, M. (ed). (1996). Field Epidemiology. Oxford University Press.

6. Holstein, JA and Gubrium, JF. (1997). Active Interviewing. In Silverman, D. (Ed.) Qualitative Research: Theory, Method, and Practice. London: Sage Publications, pp. 113-129.

7. Last, J.M. (2001). A Dictionary of Epidemiology: 4th Edition. Oxford University Press: New York.

Page 138: Final october interviewing_techniques

References and Resources

8. Levy, P. and Lemeshow, S. (1991). Sampling of Populations. John Wiley & Sons.

9. Ramsey, S. et al (2005). Using GIS and GPS to Improve Public Health Response. Guilford County, NC Health Department Public Health Regional Surveillance Team 5.

10. Rubin, HJ and Rubin, IS.  (1995). Interviews as Guided Conversations. Qualitative Interviewing: The Art of Hearing Data. Sage Publications, pp. 1-16, 122-144.

11. Salant, P. and Dillman, D. (1994). How to Conduct Your Own Survey. John Wiley & Sons.

Page 139: Final october interviewing_techniques

References and Resources

12. 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.

13. U.S. Census Bureau (2005). Profile of Selected Housing Characteristics by State: Census 2000 Summary File 3 http://factfinder.census.gov/servlet/QTTable?_bm=n&_lang=en&qr_name=DEC_2000_SF3_U_DP4&ds_name=DEC_2000_SF3_U&geo_id=04000US51

14. Weiss, R.S. (1994). Learning from Strangers: The Art and Method of Qualitative Interview Studies. New York: The Free Press.

15. Wiggins, B. and Deeb-Sossa, N. (2000). Conducting Telephone Surveys. Chapel Hill, NC: Odum Institute for Research in Social Science.