Now we’ll get into more of the details surrounding the development of a biodata instrument. To help illustrate how such instruments are developed — and how the collection and scoring of this type of information can enhance selection systems — we’ll review the development of IPMA-HR’s Correctional Officer Biodata Questionnaire (CO-BDQ) through its Technical Report, which describes in detail the steps IPMA-HR and Bruce Davey and Associates (BDA) took to develop and validate the 120-item test.
By the end of this article, you should have a clearer picture of what information is gathered in order to develop a biodata instrument, how it relates to the job, how candidates are tested and how their results determine how good of a “fit” they are with the profile developed of successful job performers. Keep in mind throughout that, as with any selection instrument, the CO-BDQ had to be two things: reliable (i.e., measure what it measures consistently) and valid (i.e., measure what it is supposed to measure).
Developers wanted the CO-BDQ to measure the potential for good job performance coupled with low probability of turnover — doing this consistently would prove its reliability. Because of the nature of this type of instrument and the type of information it gathers and utilizes, extra effort had to be made to demonstrate its efficacy. Continue reading
Those involved in the hiring process generally agree: the more you know about each candidate, the more likely you are to make good hiring decisions. To that end, successful selection systems — i.e., valid and reliable — for police and corrections officers typically do not rely on just one type of test. As the term “systems” suggests, selection specialists develop a battery of tests and methods to increase the accuracy of their agency’s hiring decisions.
Job analyses plays a critical part in the development of effective public safety selection systems by successfully identifying the tasks involved in the job, as well as the knowledge, skills, abilities and personal characteristics (KSAPs) necessary to perform them. While test instruments are developed to measure the degree to which candidates possess the prerequisite KSAPs, not all KSAPs identified in the job analyses are measured.
Deciding which KSAPs would be left out was primarily a matter of how easy it was to measure. If it could be measured by traditional test instruments, such as multiple-choice written tests and structured interviews, then it was included. As a result, exam and selection plan outlines focused on dividing the KSAPs based on the availability and ability of test instruments: if a KSAP could not be measured or if measuring it was too expensive or time-consuming, it was added to the “no” column. Continue reading