Interviewer Performance, defined in this paper as the ability of an interviewer to contact and convince respondents, is generally assessed by call centres in using descriptive measures such as the number of completed interviews, the number of completed interviews per hour, etc. Other more comprehensive performance indicators such as the cooperation rate at first contact and Net Contribution to Performance Index have been developed over the past few years. However many factors might impact interviewers’ performance in a centralized call centre environment. In addition to the interviewer’s characteristics and environmental factors, the type and portfolio of cases called, the effort already put into these cases, the time the call is made and the general productivity of the survey at the moment at which the call is made are some of these potential influencing factors...