These questions represent 16% of the total question set. These questions may therefore need to be replaced by other questions which may be considered of optimal difficulty. Those having an optimal level of difficulty would have a difficulty index (P-value) of 0.50 0r 50% and those which were considered to0 easy would have a P- value of between 90 and 100 %. These are:
From the information above and the Bar Graph in the Appendix it is clear to see that the easy questions are concentrated from the 1st to the 14th question, with the highest percentage (38%) coming from Chapter 15. A total of eight (8) questions were taken from this chapter.
In applying the difficulty index five (5) questions fell below the optimum P- value of 0.50. These are considered fairly difficult and the percentage of candidates who answered them correctly ranged from 31 to 46%. The quiz items were as follows.
This represents 10% of the total test items. Here Chapter 15 is featured once again. This additional information implies that 50% of the questions taken from that chapter may not be appropriate. I say may because there are various reasons why they may be allowed to remain. Low P-values normally suggest difficult items. It could mean that the question confused some candidates or that the contents related to those test items may need to be re-taught. The percentages noted above are considered above the P-value that would require the content to be re-taught.
Further analysis could be carried out on items on the quiz that may be discriminatory. High values would be suggestive of discrimination (R). When a test item has a high R value it suggests that the candidates who received high test scores got the item correct while those with low scores in the quiz got the item incorrect. The Bar Graph and Pie Chart in the Appendix gives a graphical illustration of the results of the