Table 4.
DIF for the 11 YFAS2 diagnostic criteria
| Diagnostic criteria | t value | P value | DIF contrast* |
|---|---|---|---|
| Gender DIF | |||
| Substance taken in larger amount and for longer period than intended (#1+#2+#3) | − 2.46 | 0.01 | − 0.70 |
| Persistent desire or repeated unsuccessful attempts to quit (#4+#25+#31+#32) | − 1.60 | 0.11 | − 0.49 |
| Much time/activity to obtain, use, recover (#5+#6+#7) | − 1.36 | 0.18 | − 0.48 |
| Important social, occupational, or recreational activities given up or reduced (#8+#10+#18+#20) | 2.43 | 0.02 | 0.58 |
| Use continues despite knowledge of adverse consequences (e.g., emotional problems, physical problems) (#22+#23) | − 0.19 | 0.85 | − 0.05 |
| Tolerance (marked increase in amount; marked decrease in effect) (#24+#26) | − 1.06 | 0.29 | − 0.34 |
| Characteristic withdrawal symptoms; substance taken to relieve withdrawal (#11+#12+#13+#14+#15) | − 2.39 | 0.02 | − 0.61 |
| Continued use despite social or interpersonal problems (#9+#21+#35) | 3.10 | 0.00 | 0.78 |
| Failure to fulfill major role obligation (e.g., work, school, home) (#19+#27) | 4.68 | 0.00 | 1.12+ |
| Use in physically hazardous situations (#28+#33+#34) | − 1.97 | 0.05 | − 0.46 |
| Craving, or a strong desire or urge to use (#29+#30) | − 0.94 | 0.35 | − 0.29 |
| BMI DIF | |||
| Substance taken in larger amount and for longer period than intended (#1+#2+#3) | − 0.08 | 0.94 | − 0.02 |
| Persistent desire or repeated unsuccessful attempts to quit (#4+#25+#31+#32) | 0.63 | 0.53 | 0.21 |
| Much time/activity to obtain, use, recover (#5+#6+#7) | − 0.69 | 0.49 | − 0.25 |
| Important social, occupational, or recreational activities given up or reduced (#8+#10+#18+#20) | − 0.91 | 0.36 | − 0.23 |
| Use continues despite knowledge of adverse consequences (e.g., emotional problems, physical problems) (#22+#23) | 1.06 | 0.29 | 0.32 |
| Tolerance (marked increase in amount; marked decrease in effect) (#24+#26) | − 0.54 | 0.59 | − 0.18 |
| Characteristic withdrawal symptoms; substance taken to relieve withdrawal (#11+#12+#13+#14+#15) | 0.57 | 0.57 | 0.15 |
| Continued use despite social or interpersonal problems (#9+#21+#35) | − 1.66 | 0.1 | − 0.45 |
| Failure to fulfill major role obligation (e.g., work, school, home) (#19+#27) | − 0.76 | 0.45 | − 0.19 |
| Use in physically hazardous situations (#28+#33+#34) | 1.58 | 0.12 | 0.39 |
| Craving, or a strong desire or urge to use (#29+#30) | 0.84 | 0.40 | 0.27 |
DIF differential item functioning
*Positive values indicate that the probability of the item endorsement is easier for male participants than female participants; easier for participants with BMI < 24 than those with BMI ≥ 24
+DIF contrasts over 1 indicate substantial DIF