Skip to main content
. Author manuscript; available in PMC: 2021 Oct 18.
Published in final edited form as: Assessment. 2020 Aug 29;28(3):858–876. doi: 10.1177/1073191120952889

Table 3.

Differential Item Functioning Results Comparing ASD and TD Groups

χ2(4) p-value UIDS ESSD Parametersa
1. Sadness 21.59 < 0.001 0.056 0.078 —
2. Pessimism 17.10 0.003 0.030 −0.009 d1, d2, d3
3. Past Failure 25.46 < 0.001 0.130 −0.159 a1, d2, d3
6. Punishment Feelings 24.77 < 0.001 0.122 −0.192 a1, d1, d2, d3
7. Self-Dislike 13.11 0.011 0.019 −0.020 d3
8. Self-Criticalness 38.91 < 0.001 0.064 0.065 d1, d3
9. Suicidal Thoughts or Wishes 39.33 < 0.001 0.093 −0.220* d1
10. Crying 18.84 0.002 0.042 −0.013 d3
11. Agitation 13.29 0.011 0.076 0.138 d1
12. Loss of Interest 15.84 0.004 0.072 0.013 d1
13. Indecisiveness 54.73 < 0.001 0.126 −0.183 d2, d3
14. Worthlessness 15.62 0.004 0.051 −0.041 a1, d2
15. Loss of Energy 17.64 0.002 0.112 −0.141 d1
17. Irritability 29.89 < 0.001 0.130 0.219* d1, d2
18. Changes in Appetite 16.94 0.003 0.101 −0.182 d3
19. Concentration Difficulty 38.73 < 0.001 0.133 −0.205* d2
20. Tiredness or Fatigue 12.36 0.015 0.096 −0.106 —
21. Loss of Interest in Sex 25.15 < 0.001 0.117 0.233* d1
Differential Test Functioning: UETSDS = 0.524 ETSSD = −0.039
Multi-group Model Fit: C2(349) = 1241.4 CFIC2 = 0.990 RMSEAC2 = 0.036

Note. Results indicate omnibus Wald DIF tests using the iterative anchor-selection method of Cao et al., (2017). p-values are corrected for a 5% false discovery rate. Parameters that were significantly different between groups when tested alone with follow-up Wald tests (FDR < 0.05) are indicated in the Parameters column. UIDS = Unsigned Expected Item Score Difference in the Sample; ESSD = Expected Score Standard Deviation (in Cohen’s d metric); a1 = general factor slope parameter; d1–d3 = item intercept parameters; UETSDS = Unsigned Expected Test Score Difference in the Sample; ETSSD = Expected Test Score Standardized Difference (in Cohen’s d metric).

a

Parameters in bold are larger (i.e., more discriminating for a parameters and “easier” for d parameters) in the ASD group. Larger values of a indicate that the item is more strongly related to the latent trait in the ASD group, whereas larger values of d indicate that a given item response is endorsed at lower latent trait levels in the ASD group than the TD group.

*

Practically significant DIF (i.e., |ESSD| > 0.2)