Psychometric testing

Psychometric testing was conducted to examine the newly developed HCAT, including the factor structure, internal consistency reliability and test-retest reliability. A population-based sample including a total of 130 final-year nursing students who have completed their Transition to Practice clinical attachment was recruited. The students were invited to self-evaluate their clinical competence using the HCAT. Demographic data (e.g. age, gender and ethnicity) was also obtained. To investigate test-retest reliability, 30 students from the primary group were invited to complete the HCAT two weeks after the first evaluation.

Data were analysed using SPSS Version 22.0. Data were examined for missing values. Six cases had missing data spread across 13 items. Missing data was imputed with the mean response for the respective item. An exploratory factor analysis (EFA) was conducted to examine the underlying dimensions of the HCAT. EFA is a powerful and elegant statistical technique to address an essential scientific goal of elucidating the underlying meaning of concepts of a newly developed tool [16]. Internal consistency was evaluated using Cronbach’s alpha and item-to-total correlation. Cronbach’s alpha coefficient indicates how well a group of items together measure the trait of interest [16]. The item-to-total correlation, which assesses the extent to which an item is related to the remainder of its subscale with the item omitted, should exceed .40 [25]. Test-retest reliability was evaluated using intraclass correlation coefficient (ICC). The scores from different time points can then be correlated to evaluate the stability of the tested tool over time [16].