[Equating scores using bridging stations on the clinical performance examination]

This study examined the use of the Tucker linear equating method in producing an individual student's score in 3 groups with bridging stations over 3 consecutive days of the clinical performance examination (CPX) and compared the differences in scoring patterns by bridging number.

Data were drawn from 88 examinees from 3 different CPX groups-DAY1, DAY2, and DAY3-each of which comprised of 6 stations. Each group had 3 common stations, and each group had 2 or 3 stations that differed from other groups. DAY1 and DAY3 were equated to DAY2. Equated mean scores and standard deviations were compared with the originals. DAY1 and DAY3 were equated again, and the differences in scores (equated score-raw score) were compared between the 3 sets of equated scores.

By equating to DAY2, DAY1 decreased in mean score from 58.188 to 56.549 and in standard deviation from 4.991 to 5.046, and DAY3 fell in mean score from 58.351 to 58.057 and in standard deviation from 5.546 to 5.856, which demonstrates that the scores of examinees in DAY1 and DAY2 were accentuated after use of the equation. The patterns in score differences between the equated sets to DAY1, DAY2, and DAY3 yielded information on the soundness of the equating results from individual and overall comparisons.

To generate equated scores between 3 groups on 3 consecutive days of the CPX, we applied the Tucker linear equating method. We also present a method of equating reciprocal days to the anchoring day as much as bridging stations.