Table 5.
IRT Calibration Results of the Persian Mental Health Literacy Scale Item Bank (N= 992)
| Item-ID | Mean (SD) | Item-Total Correlation | Cronbach’s Alpha If Deleted | IRT | ||||
|---|---|---|---|---|---|---|---|---|
| Item Discrimination | B1 | B2 | B3 | B4 | ||||
| MHL1 | 2.50 (0.86) | 0.30 | 0.73 | 1.26 | −1.91 | −0.07 | 2.04 | — |
| MHL2 | 2.65 (0.84) | 0.32 | 0.73 | 1.46 | −2.06 | −0.38 | 1.60 | — |
| MHL3 | 2.79 (0.89) | 0.31 | 0.73 | 1.14 | −2.48 | −0.65 | 1.31 | — |
| MHL4 | 2.56 (0.86) | 0.36 | 0.73 | 1.60 | −1.74 | −0.18 | 1.64 | — |
| MHL5 | 2.48 (0.82) | 0.35 | 0.73 | 1.42 | −1.85 | −0.05 | 2.10 | — |
| MHL6 | 2.38 (0.85) | 0.40 | 0.73 | 1.76 | −1.37 | 0.09 | 2.00 | — |
| MHL7 | 2.37 (0.90) | 0.42 | 0.73 | 1.61 | −1.30 | 0.18 | 1.82 | — |
| MHL8 | 2.38 (1.08) | 0.34 | 0.73 | 1.13 | −0.98 | −0.06 | 1.69 | — |
| MHL9 | 2.86 (0.89) | 0.27 | 0.73 | 0.84 | −3.09 | −1.12 | 1.50 | — |
| MHL10 | 2.46 (0.87) | 0.05 | 0.74 | 0.29 | −6.78 | 0.54 | 6.69 | — |
| MHL11 | 2.93 (0.84) | 0.25 | 0.73 | 0.80 | −3.67 | −1.45 | 1.48 | — |
| MHL12 | 2.68 (0.88) | 0.07 | 0.74 | 0.32 | −7.00 | −1.17 | 4.58 | — |
| MHL13 | 2.68 (0.89) | 0.38 | 0.73 | 1.23 | −2.02 | −0.55 | 1.62 | — |
| MHL14 | 2.38 (0.99) | 0.18 | 0.74 | 0.45 | −2.88 | 0.31 | 4.15 | — |
| MHL15 | 2.42 (0.98) | 0.11 | 0.74 | 0.34 | −4.05 | 0.36 | 5.16 | — |
| MHL16 | 3.24 (1.04) | 0.29 | 0.73 | 0.57 | −4.76 | −2.33 | 0.34 | 4.31 |
| MHL17 | 3.36 (1.11) | 0.23 | 0.74 | 0.47 | −5.59 | −2.70 | −0.38 | 4.34 |
| MHL18 | 3.63 (1.08) | 0.25 | 0.73 | 0.60 | −4.96 | −2.90 | −1.22 | 2.56 |
| MHL19 | 3.54 (1.04) | 0.23 | 0.74 | 0.53 | −5.85 | −3.04 | −1.07 | 3.53 |
| MHL20 | 2.33 (1.08) | 0.10 | 0.75 | −0.16 | 7.60 | −3.97 | −10.07 | −19.71 |
| MHL21 | 2.95 (1.17) | 0.10 | 0.74 | −0.06 | 38.43 | 6.42 | −9.93 | −39.88 |
| MHL22 | 3.55 (1.09) | 0.14 | 0.74 | 0.35 | −9.24 | −4.27 | −1.10 | 4.11 |
| MHL23 | 3.20 (1.11) | 0.18 | 0.74 | −0.07 | 36.74 | 14.70 | −4.12 | −29.52 |
| MHL24 | 3.58 (1.15) | 0.32 | 0.73 | 0.26 | −11.21 | −5.38 | −1.72 | 4.67 |
| MHL25 | 3.89 (0.95) | 0.17 | 0.74 | 0.25 | −14.82 | −9.43 | −4.38 | 4.25 |
| MHL26 | 3.74 (1.17) | 0.18 | 0.74 | 0.33 | −9.33 | −4.31 | −2.68 | 2.63 |
| MHL27 | 4.29 (0.86) | 0.28 | 0.73 | 0.61 | −6.57 | −5.06 | −3.86 | 0.28 |
| MHL28 | 4.12 (0.91) | 0.29 | 0.73 | 0.54 | −7.19 | −5.22 | −3.01 | 0.99 |
| MHL29 | 2.56 (1.10) | 0.28 | 0.73 | −0.03 | 41.54 | 2.81 | −41.20 | −99.04 |
| MHL30 | 2.35 (1.16) | 0.36 | 0.73 | 0.04 | −17.86 | 6.71 | 29.62 | 78.93 |
| MHL31 | 2.25 (1.10) | 0.34 | 0.73 | −0.04 | 19.82 | −10.57 | −43.89 | −108.40 |
| MHL32 | 1.94 (1.02) | 0.26 | 0.73 | −0.17 | 1.54 | −5.86 | −13.90 | −25.27 |
| MHL33 | 1.33 (0.66) | 0.16 | 0.74 | −0.28 | −4.08 | −9.06 | −16.43 | −20.74 |
| MHL34 | 1.35 (0.74) | 0.07 | 0.74 | −0.34 | −3.77 | −6.48 | −11.48 | −15.03 |
| MHL35 | 1.66 (0.90) | 0.21 | 0.74 | −0.15 | −1.58 | −11.24 | −19.29 | −34.64 |
Note: The first option to answer each question in the GRM model is as a reference category.
Abbreviations: MHL, mental health literacy; IRT, item response theory; GRM, graded response model.