Evaluation of the effect of items’ format and type on psychometric properties of sixth year pharmacy students clinical clerkship assessment items

Table 3 Item Performance Characteristics Based on Different Item Properties and Layers (N = 173)

	Level of Difficulty Mean (SD)	Discriminating Index Mean (SD)	Point-biserial Mean (SD)
Item Format
Case Based	63.7 (19.7)	.34 (.18)	0.34 (.17)
Noncase Based	59.2 (19)^NS	.38 (.22)^NS	0.30 (.16)^NS
Item Type/Structure
Open-ended/Essay	63.4 (18)	.39 (.18)	.39 (.15)
Multiple Choice	61.7 (21.5)^NS	.31 (.19)*	.26 (.16)*
Number of Choices/options
4-option Items	51.3 (19.1)	.30 (.18)	.24 (.14)
5-option Items	67.2 (21.5)*	.31 (.19)^NS	.29 (.17)^NS
Item Format: Item Type/Structure
Case Based: Open-ended	64.5 (18.3)	.37 (.17)	.38 (.16)
Case Based: MCQs	62.2 (22.2)^NS	.29 (.17)*	.26 (.15)*
Noncase Based: Open-ended	54.2 (11.7)	.54 (.17)	.45 (.07)
Noncase Based: MCQs	61 (20.8)^NS	.33 (.21)*	.25 (.18)*
Item Format: Number of Choices/options
Case Based: 4-option	50.3 (20.4)	.3 (.17)	.25 (.13)
Case Based: 5-option	73.7 (18.8)*	.27 (.16)^NS	.29 (.17)^NS
Noncase Based: 4-option	53.5 (16.6)	.33 (.22)	.21 (.17)
Noncase Based: 5-option	59 (22.6)*	.36 (.23) ^NS	.28 (.19)^NS
Item Type/Structure: Item Format
Open-ended: Case Based	64.5 (18.3)	.37 (.17)	.38 (.16)
Open-ended: Noncase Based	54.2 (11.8)^NS	.54 (.17)*	.45 (.07)*
MCQ: Case Based	62.2 (22.2)	.29 (.1)	.20 (.1)
MCQ: Noncase Based	61 (20.8)^NS	.33 (.1)*	.26 (.1)*
Number of Choices/options: Item Format
4-option: Case Based	50.3 (20)	.3 (.17)	.25 (.13)
4-option: Noncase Based	53.6 (17)*	.33 (.22)^NS	.21 (.17)^NS
5-option: Case Based	73.7 (18.8)	.27 (.16)	.29 (.17)
5-option: Noncase Based	60 (22.5)*	.36 (.23)^NS	.28 (.16)^NS

ISSN: 1472-6920