DEVELOPMENT AND EVALUATION OF A CERTIFICATION TEST FOR FARM EQUIPMENT MECHANICS IN THE AREA OF ELECTRICAL SYSTEMS

Problem. A major problem faced by farm implement dealers in hiring mechanics is determining the knowledge and skill level of the prospective employees. Some experts suggested the use of basic certification tests to provide the necessary information.;Method. A pool of 211 multiple-choice test items were developed. A panel of 22 experts in this area reviewed the items for context validity and ranked each item according to its importance. A one-hour, 100-item test was developed using the highest ranked items. A personal data sheet determined the background knowledge of each examinee. The test was administered to 206 technical school students and 21 mechanics. The mechanics' supervisors were asked to rate the skill and ability of each mechanic in the area of electrical systems.;Findings. The reliability coefficient of the test was as follows: .92 for the total group; .92 for the student group and .88 for the mechanic group. Mechanics obtained significantly higher scores than all students. Students in their second year of school or students with some knowledge of electricity did a significantly better job than students in their first year or those with no background in electricity (construct validity). A strong correlation (r = .74) was found between the supervisors' ratings and mechanics' test scores (criterion-related validity). All but 20 items fulfilled the requirements for difficulty index (10%-90%), discrimination index (higher than or equal to .20) and distractor effectiveness.;Conclusions. The test was found to be highly reliable and valid. The test covered basic level electricity and could be used to differentiate, with high levels of accuracy, between individuals with various levels of knowledge and skill in the area of farm equipment electrical systems.;The purpose of this study was to develop a valid and reliable certification test in the area of electrical systems.