measuring interviewer effects on survey error in share annelies blom julie korbmacher ulrich krieger
TRANSCRIPT
Motivation
Korbmacher and Schröder (2010): consent to record linkage (SHARE wave 3)
„The decision making process is mainly influenced by the interview situation which in turn is driven by the interviewer-respondent-interaction ”
The role of the interviewer
…make contact …gain cooperation …ask survey questions …conduct measurements …record answers and measurements …maintain respondents’ motivation throughout
the interview
Standardized interviews to reduce variation in the entire data collection process
Types of interviewer effects in surveys
Interviewer
Measurement
Unit nonresponse
Contact Cooperation
Item nonresponse
Nonresponse- Error
Measurement- Error
Survey of Health, Ageing and Retirement in Europe (SHARE)
Multidisciplinary Micro data on health, socio-economic status,
social and family networks bi-annual, longitudinal (wave 1 in 2004) 20 European countries
SHARE-DE (Wave 4) specials: Record linkage (Pilot in wave 3) Collecting biomarkers Nonresponse experiment
Interviewer effects examined in SHARE Germany Wave 4
Interviewer
Income item nonresponse
Consent to biomarkers
blood pressure
height
waist circumference
dried blood spots
Unit nonresponse (incentives)
No unconditional incentive
10€ unconditional incentive
20€ unconditional incentive
40€ unconditional incentive
Consent to record linkage
Measuring and Explaining interviewer effects
Step 1: Measuring interviewer effects Step 2: Explaining interviewer effects
Who are the SHARE interviewers? Interviewer questionnaire
Underlying assumptions: Interviewers differentially impact on the data collection
process This differential impact is related to their – conscious
and subconscious – appearance and actions These actions can be explained by characteristics
collected in an interviewer survey
Interviewer survey
2011 Interviewer Training Wave 4 (trained 197
interviewers) Paper-and-pencil Voluntary and no incentives At the end of the training session Response rate: 83%
Link via InterviewerID to SHARE Survey data!
Conceptual framework
4 dimensions of interviewer characteristics
Unit non-response
Unit non-response (incentives)
Consent to biomarker collection
Consent to record linkage
Item nonresponse (income)
General attitudes
Own behavior
Experience with measurements
Expectations
5 aspects of SHARE Wave 4 (Germany)
Conceptual framework
General interviewer attitudes Reasons for being an interviewer Attitudes towards best practice Trust and data protection concerns
Interviewers‘ own behavior Interviewer as respondents Membership in social networks Income Blood donation Hypothetical questions:
disclose sensitive information consent to record linkage consent to biomarkers
Conceptual framework
Interviewers’ experience with measurements Conducting standardized interviews SHARE Conducting blood sugar tests
Interviewers’ expectations of unit response, consent and item response rates Expected response and consent rates:
Different incentive groupsBiomarker measurementsRecord linkage Income
Some results of the interviewer survey
Nonresponse
02
04
06
08
01
00
Expected unit response rates
no incentive 10 Euro20 Euro 40 Euro
Interviewers were confident that the higher the value of the incentive the more successful they would be in recruiting respondents.
• Interested in learning about the lives of other people
• Important to work on research that is relevant to society
expect higher RRs
expect lower RRs• Using of social networks (facebook)
Some results of the interviewer survey
Consent to record linkage Expected consent rate: 59,2%
Interviewers who would reveal personal information expect a significantly higher consent rate.
SSN Telephone number Private Address Address of health insurer
Some results of the interviewer survey
Interviewers who would consent to data linkage expect a significantly higher consent rate. Credit historyEmployment historyMedical recordsSocial benefits
Interviewer who are part of social networks expect significantly lower record linkage rates.