Interviewer effects in a cohort study. Results from the Massachusetts Women's Health StudyWomen’s Health Research Faculty Publications
UMMS AffiliationNew England Research Institutes
SubjectsDepression; *Effect Modifiers (Epidemiology); Female; Humans; Logistic Models; Massachusetts; *Menopause; Middle Aged; Odds Ratio; Predictive Value of Tests; Prospective Studies; Telephone; *Women's Health
AbstractAlthough interviewer error is widely recognized as an important source of variation in epidemiologic investigations, scant published information exists documenting the impact of interviewer variation on study findings. Using data from the Massachusetts Women's Health Study, a population-based cohort study of 2,569 middle-aged women (1982-1987), the authors evaluated interviewer variation in responses to different types of questions, and assessed the impact of interviewer variation on inferences derived from study data. Respondent sociodemographic and lifestyle characteristics were similar for the four study interviewers at the first follow-up. No interviewer variation was detected for questions concerning recall of specific events, but responses to questions regarding recall of subjective or personal information or those which required further probing did differ significantly by interviewer. Adjustment for interviewer effects had no impact on the conclusions obtained from one analysis of predictors of depression, despite significant interviewer variation in the outcome and predictor variables, but it did change conclusions from an analysis of the impact of support networks on psychological symptoms, wherein the interviewer variable was strongly related to the outcome after data were controlled for predictor variables. Given these findings, examination of data for interviewer effects is advisable despite incorporation of quality control measures in a study's design.
Rights and PermissionsCitation: Am J Epidemiol. 1997 Sep 1;146(5):429-38.
Related ResourcesLink to article in PubMed
Citation InformationCatherine B. Johannes, Sybil L. Crawford and John B. McKinlay. "Interviewer effects in a cohort study. Results from the Massachusetts Women's Health Study" Vol. 146 Iss. 5 (1997) ISSN: 0002-9262 (Print)
Available at: http://works.bepress.com/crawfords/34/