2004 Public Health Training and Information Network (PHTIN) Series

1
2004 Public Health Training and Information
Network (PHTIN) Series
2
Site Sign-in Sheet

• Please mail or fax your sites sign-in sheet to
• Linda White
• NC Office of Public Health Preparedness
• and Response
• Cooper Building
• 1902 Mail Service Center
• Raleigh, NC 27699
• FAX (919) 715 - 2246

3
Outbreak Investigation Methods

• From Mystery to Mastery

4

5
2004 PHTIN Training Development Team

• Pia MacDonald, PhD, MPH - Director, NCCPHP
• Jennifer Horney, MPH - Director, Training and
  Education, NCCPHP
• Anjum Hajat, MPH Epidemiologist, NCCPHP
• Penny Padgett, PhD, MPH Epidemiologist and
  Surveillance Officer, NCCPHP
• Amy Nelson, PhD - Consultant
• Sarah Pfau, MPH - Consultant
• Amy Sayle, PhD, MPH - Consultant
• Michelle Torok, MPH - Doctoral Candidate
• Drew Voetsch, MPH - Doctoral Candidate
• Aaron Wendelboe, MSPH - Doctoral student

6
Future PHTIN Sessions

• September 14th. . . . . . .Designing
  Questionnaires
• October 12th. . . . . . . . . Analyzing Data
• December 14th. . . . . . . Risk Communication
• Each session will be on a Tuesday from 1000 am -
  1200 pm
• (with time for discussion)

7
Session I VI Slides

• After the airing of each session, NCCPHP will
  post PHTIN Outbreak Investigation Methods series
  slides on the following two web sites
• NCCPHP Training web site
• http//www.sph.unc.edu/nccphp/training/index.html
• North Carolina Division of Public Health, Office
  of Public Health Preparedness and Response
• http//www.epi.state.nc.us/epi/phpr/

8
Session III

• Interviewing Techniques

9
Todays Presenters

• Anjum Hajat, MPH
• Epidemiologist, NC Center for Public Health
  Preparedness
• Martha Salyers, MD, MPH
• Team Leader, Public Health Regional Surveillance
  Team 6,
• Buncombe County Health Center
• Sarah Pfau, MPH
• Moderator

10
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 and telephone interview methods

11
Learning Objectives (contd.)

• Understand the advantages and disadvantages of
  mail and web based survey implementation
• Know what to cover in interviewer training
• Recognize good interview techniques
• Understand confidentiality concerns from the
  perspectives of both the respondent and the
  outbreak investigation

12
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 additional studies
• Implement and evaluate control measures
• Communicate findings

13
Interviewing Techniques

• Introduction

14
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

15
Role of Interviews in Outbreak Investigations

• Primary purpose data collection
• Case identification
• Risk factor identification
• Hypothesis generation

16
Interviewing Methods

• Interviewer Administered
• Face-to-face
• Telephone
• Self Administered
• Mail-out
• Email
• Web-based
• Combination of 1 and 2

17
Questionnaire Design

• Interview Method Influenced by
• Length and format of questionnaire
• Question types used in a survey
• Cost considerations for survey implementation

18
Questionnaire Design

• September 14th PHTIN Session
• Designing Questionnaires

19
Sampling
20
Sampling

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

21
Sampling
Source Pop Students (12,000)
Sampled pop (150 students)
22
Sampling

• Why Sample?
• Because it is more efficient saves time and
  money!

23
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.

24
Sampling

• Types of Sampling
• Simple Random Sample (SRS)
• Randomly select persons to participate in study.
  There are many variations of SRS.
• Convenience Sample
• Choose those individuals who are easily
  accessible.

25
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

26
Sampling

• Additional Resources
• http//www.sph.unc.edu/nccphp/training/all_trainin
  gs/at_sampl.htm
• Sampling Case Studies
• Survey Sampling Precision, Sample Size, and
  Conducting a Survey
• Survey Sampling Terminology and Methods

27
Response Rates
28
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.

29
Response Rates

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

30
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)

31
Response Rates

• What is an average response rate?

32
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.

33
Interviewer AdministeredData Collection
Considerations
34
Interviewer Administered Data Collection

• Advantages and disadvantages of face-to-face
  interviews
• Advantages and disadvantages of telephone
  interviews
• Computer Assisted Interviews
• PHRST Region 5 PDA initiative

35
Interviewing Methods

• Interviewer Administered
• Face-to-face
• Telephone

36
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)

37
Face-to-Face Interview

• Disadvantages
• Costly
• Potential for interviewer error
• Less anonymous than self-administered
• Participants less inclined to be honest

38
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

39
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)

40
Percentage of Households with No Telephone
Service by County, NC
Data source 2000 U.S. Census
41
Computer Assisted Interviewing (CAI)

• CATI Telephone
• CAPI Personal
• ACASI Audio

42
CAPI ExamplePHRST Region 5

• In the PHRST Region 5, NC public health
  professionals are training to use PDAs for
  outbreak investigation and rapid needs assessment
  face-to-face interviews.
• PDA Personal Digital Assistant, also sometimes
  called hand-held computers, palmtops, and pocket
  computers
• To learn more about this technology initiative,
  please contact Steve Ramsey at sramsey_at_co.guilford
  .nc.us

43
CAPI Example PHRST Region 5
44
Self AdministeredData Collection Considerations
45
Self-administeredData Collection

• Advantages and disadvantages of mailed
  questionnaires
• Advantages and disadvantages of Web-based
  questionnaires

46
Interviewing Methods

• Self Administered
• Mail-out
• Email / Web-based

47
Mailed Questionnaire

• Advantages
• More anonymous
• May collect more honest responses
• No interviewer error
• Less expensive
• Respondent has more time to think about question

48
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

49
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

50
Web-based Questionnaire

• For a list of vendors that provide Web-based
  survey tools, please visit
• http//www.surveymonkey.com/Pricing.asp

51
Web-based Questionnaire

• Example 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 Streptococcus
• pneumoniae. N Engl J Med. 2003348 (12)1112-21.
  

52
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

53
Question and Answer Opportunity
54
Standardizing Interviews
55
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

56
Error

• Interviewer Error
• Definition
• Deviation from expected answer due to the
  effects of interviewers.

57
Interviewer ErrorExample Gonorrhea outbreak

• Bias
• Interviewers are not told to probe on the sexual
  history section.

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

58
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.

59
Standardizing Interviews

• Contributing Factors
• Question wording
• Interviewer selection
• Interviewer training
• Interviewing procedures
• Supervising interviewers

60
1. Question Wording
61
Question Wording

• Criteria for Standardized Interview Questions
• Must be fully scripted
• Must mean the same thing to every respondent
• More discussion to follow in the September 14th
  PHTIN session, Designing Questionnaires

62
2. Interviewer Selection
63
Interviewer Selection

• Criteria for Telephone Interviewer Selection
• Ability to read questions fluently
• Clear and pleasant telephone voice
• Responds quickly to respondents questions
• Reliability

64
Interviewer Selection

• Criteria for Face-to-Face Interviewer Selection
• Logistical skills (reading maps)
• Good interpersonal skills
• Independent workers
• Reliability
• In certain circumstances, parallel demographic
  characteristics among interviewers and
  interviewees

65
3. Interviewer Training
66
Interviewer Training

• Training is NOT optional!
• Trainings must be interactive
• Interviewers must practice reading questions out
  loud
• Provide support documentation (manual)

67
Interviewer Training

• What to cover
• Purpose of survey
• Respondent selection process
• Administering questionnaire
• Logistics
• Answering respondents questions
• Tracking calls / completed surveys
• Confidentiality

68
Interviewer Training

• Respondent Selection Process
• Provide proxy respondent rules for adults and
  children because proxy response impacts
• Data quality
• Sampling

69
Interviewer Training

• Questionnaire Administration
• To establish legitimacy of the survey upon first
  contact, tell the respondent
• Who is calling
• What is requested
• Why respondent should cooperate
• How respondent was chosen

70
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)

71
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

72
Interviewer Training

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

73
Interviewer Training

• Suggested Interviewer Manual Contents
• Background information
• Fieldwork
• Interviewing techniques
• Survey instrument terms and definitions

74
5 minute break
75
Interviewer Training Program Example

• Behavioral Risk Factor Surveillance System (BRFSS)

76
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

77
BRFSS Interviewer Training

• On-line interviewer training available at
• http//apps.nccd.cdc.gov/BRFSS_Training_Int/overv
  iew.asp
• General information about BRFSS
  http//www.cdc.gov/brfss/

78
4. Interviewing Procedures
79
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

80
Interviewing Procedures

• Read questions exactly
• Read entire question before accepting an answer
• Clarify questions if necessary

81
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

82
Interviewing Procedures

• Probe
• A probe is a standardized way to obtain
  additional information from a respondent.
• Use probes when a respondents answer is unclear
  or irrelevant.

83
Probe

• Examples 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."

84
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?

85
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

86
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
• None d. 3 times
• Once e. More than 3 times
• Twice
• Respondent
• Oh, gee, I didnt go very often . . . maybe a
  few times.

87
Probing versus Leading

• Example
• Interviewer Probe (correct)
• Which would be closer none, once, twice, 3
  times, or more than 3 times?
• Interviewer Leading (incorrect)
• So, would you say twice, or three times?
• b. Do you mean twice, or three times?

88
Interviewing Procedures

• Maintain Rapport
• An interviewer should be
• Nonjudgmental
• Noncommittal
• Objective

89
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

90
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.

91
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

92
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.

93
Question and Answer Opportunity
94
Activity Correct Interview ProceduresProbing
vs. Leading vs. Feedback

• Completion time 5 minutes

95
Activity

• Interviewer Are you still experiencing
  Diarrhea?
• Respondent 1 Im 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.

96
Activity

• Suggested Answer
• Respondent 1 Im 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.

97
Activity

• Suggested Answer
• Respondent 2
• I definitely had diarrhea last Tuesday
• Try a Probe
• OK, but are you still experiencing diarrhea?

98
Activity

• Suggested Answer
• Respondent 3 Yes
• Good Feedback I see
• Bad Feedback Are you sure? (leading)

99
5. Supervising Interviewers
100
Supervising Interviewers

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

101
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

102
Confidentiality
103
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.

104
Confidentiality

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

105
Confidentiality

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

106
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

107
Confidentiality

• Example
• Violation of respondents confidentiality from
  BRFSS training
• http//apps.nccd.cdc.gov/BRFSS_Training_Int/confid
  ential_2.asp

108
5 minute break
109
Guest Expert Lecturer

• Martha Salyers, MD, MPH
• Team Leader, PHRST 6
• Buncombe County Health Center

110
North Carolina Hurricane IsabelRapid Needs
Assessment

• September 2003

111
Rapid Needs Assessment
112
Rapid Needs Assessment

• Background
• September 20, 2003 Hurricane Isabel en route to
  NC coast (Beaufort County)
• Access to Outer Banks not possible because of
  travel restrictions
• NC Emergency Management positioned regionally for
  response

113
Rapid Needs Assessment

• Background
• RNA process had been used in other disasters,
  e.g., Ankara earthquake 1999
• Decision to perform RNA made as Isabel approached
  the NC coast
• 5 PHRSTs called to Raleigh 2 PHRSTs in affected
  regions stayed to serve their area

114
Rapid Needs Assessment

• Background
• Thirty census clusters selected for a survey
  sample across 14 counties
• Ten assessment teams comprised of Public Health
  Regional Surveillance Team (PHRST) staff, UNC
  Chapel Hill School of Public Health students, and
  state agency volunteers deployed to forward
  base in Greenville

115
Rapid Needs Assessment

• Purpose was to collect data about
• External or flood damage to homes
• Access to household utilities
• Incidence of hurricane-related illness and injury
• Access to food and water
• Access to medical care or medication
• Immediate needs

116
Needs Assessment Survey Instrument
117
Survey Instrument

• One-page survey instrument
• 24 questionnaire items
• 33 data fields
• Accompanied by a one-page explanatory notes
  form for interviewers

118
Survey Instrument
119
Interviewer Training
120
Interviewer Training

• Cooper BuildingPublic Health response base
  houses Public Health Command Center
• Approximately 2 hours / day over 2 daysrepeated
  second day for new interview team members
• Conducted by out-posted CDC staff

121
Interviewer Training

• Each item on the explanatory notes form covered
• Detailed discussion of questionnaire items
• Questionnaire produced in Spanish

122
Interview Process
123
Interview Process

• Overview
• Assessment teams deployed in official vehicles to
  selected census areas
• From starting point, moved sequentially along
  roadways to collect data from seven households
  per cluster
• Data collection was paper-based
• Total of 210 interviews completed

124
Interview Process

• Interview Teams
• Comprised of two interviewers
• Generally multi-disciplinary teams
• Radio assigned to each team

125
Interview Process

• Interview Teams
• Various approaches
• Took turns interviewing
• One person collated and numbered while the other
  interviewed
• Had a consistent interviewer

126
Interview Process

• Interview Teams
• Tools
• Identifying clothing
• ID tag
• Writing implement
• Forms
• Clipboard
• Educational materials

127
Interview Process

• Challenges
• Initial selection of census tracts
• In areas with relatively minor impact
• Differential effects
• By neighborhood, by home
• Communication
• Radios not useful cell phones unreliable
• Reading maps
• Gasoline supply

128
Interview Process

• Challenges
• Logistics at forward base
• Collating and analyzing data
• Accountability / safety
• Wanting to help

129
Lessons Learned
130
Lessons Learned

• Use existing materials wherever possible and
  tailor to your purposes
• Prepare in advance as much as possible
• Keep questionnaire brief only ask as much as you
  have to know

131
Lessons Learned

• Train interviewers consistently
• Use a software program that allows for data
  merging
• Leverage partnerships innovatively

132
Lessons Learned

• Be flexible
• Be consistentdont be tempted to change the way
  you ask questions or record answers
• Back up your data on paper

133
Lessons Learned

• Dont take unnecessary chances
• Assure consistent communication from field to
  base
• Working in teams is highly effective

134
Lessons Learned

• In a disaster, use an incident management
  structure such as ICS (Incident Command System)
  to organize response effectively
• Manageable span of control
• Accountability
• Division of responsibility
• Clear reporting relationships
• Safety first

135
Lessons Learned

• You will be overwhelmed, so prepare beforehand to
  meet the challenge
• Preposition resources
• Prepare templates, collect exemplar documents,
  have expert consultants on tap
• Exercise your staff
• Have backups
• Think innovatively about team composition

136
The Isabel Team
137
Session Summary
138
Session Summary

• The primary 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) or self administered
  (mailed, emailed, or Web-based). There are
  advantages and disadvantages to employing either
  method.

139
Session Summary

• Questionnaire design and interview methods are
  interrelated in the overall process of an
  outbreak investigation.
• 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.

140
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).

141
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.

142
Session Summary

• Sound interviewing procedures include reading
  questions exactly as they are worded probing
  inadequate answers recording answers without
  interviewer discretion and maintaining rapport
  with respondents.
• Communicate established proxy respondent rules to
  interviewers prior to survey implementation to
  avoid altering the sampling method or
  compromising data quality.

143
Session Summary

• Develop and distribute an interviewer manual to
  provide interviewer support. Such documentation
  reduces error and enhances the quality of data
  collected.
• While you will be exempt from obtaining
  Institutional Review Board clearance and informed
  consent from interviewees during an outbreak
  investigation, you should not overlook
  confidentiality issues from both the respondent
  and outbreak investigation perspectives.

144
References and Resources

• American Statistical Association (1997). What Is
  a Survey? More About Mail Surveys. Alexandria,
  VA Section on Survey Research Methods, American
  Statistical Association.
• American Statistical Association (1997). What Is
  a Survey? How to Collect Survey Data.
  Alexandria, VA Section on Survey Research
  Methods, American Statistical Association.
• Fowler, F. and Mangione, T. (1990).
  Standardizing Survey Interviewing. Newbury Park
  Sage Publications.

145
References and Resources

• Gregg, M. (ed). (1996). Field Epidemiology.
  Oxford University Press.
• Last, J.M. (2001). A Dictionary of Epidemiology
  4th Edition. Oxford University Press New York.
• Levy, P. and Lemeshow, S. (1991). Sampling of
  Populations. John Wiley Sons.
• Salant, P. and Dillman, D. (1994). How to
  Conduct Your Own Survey. John Wiley Sons.

146
References and Resources

1. Stehr-Green, J.K. (2002). Gastroenteritis at a
   University in Texas Case Study Instructors
   Guide. Atlanta, GA U.S. Department of Health
   and Human Services, Public Health Service,
   Centers for Disease Control and Prevention.
2. Wiggins, B. and Deeb-Sossa, N. (2000).
   Conducting Telephone Surveys. Chapel Hill, NC
   Odum Institute for Research in Social Science.

147
Slides from todays session

• Following this program, please visit one of the
  web sites below to access and download a copy of
  todays slides
• NCCPHP Training web site
• http//www.sph.unc.edu/nccphp/training/index.html
• North Carolina Division of Public Health, Office
  of Public Health Preparedness and Response
• http//www.epi.state.nc.us/epi/phpr/

148
Next Session September 14th1000 a.m. - Noon

• Topic Designing Questionnaires

149
Site Sign-in Sheet

• Please mail or fax your sites sign-in sheet to
• Linda White
• NC Office of Public Health Preparedness
• and Response
• Cooper Building
• 1902 Mail Service Center
• Raleigh, NC 27699
• FAX (919) 715 - 2246