Table 4.
Reliability (PSI) and targeting (item difficulty and person ability distribution, and difficulty range) of the performance scale by country. PSI: Person separation index; Mean (SD): Mean and standard deviation
| Country | Coverage | Year | Sample Size | PSI | Item Difficulty Mean (SD) |
Person Ability Mean (SD) |
Difficulty Range Thresholds min; max |
|---|---|---|---|---|---|---|---|
| Afghanistan | National | 2019 | 14130 | 0.91 | 0.29 (0.9) | −1.38 (1) | − 1.81; 2.85 |
| Cameroon, Adamawa | Regional | 2016 | 559 | 0.88 | 0.20 (0.86) | − 0.74 (0.72) | − 1.46; 2.02 |
| Chile | National | 2014 | 12265 | 0.87 | 0.23 (0.69) | −1.06 (0.87) | − 1.47; 2.34 |
| Costa Rica | National | 2018 | 2390 | 0.87 | 0.21 (0.91) | −1.18 (0.83) | −1.68; 3.54 |
| India | National (brief MDS) | 2018 | 2981 | 0.91 | 0.17 (0.53) | −0.64 (1.32) | −0.73; 1.57 |
| Laos | National (brief MDS) | 2018 | 2410 | 0.89 | 0.23 (0.72) | −0.64 (1.04) | −1.24; 1.47 |
| Pakistan, Balochistan | Regional | 2017 | 282 | 0.93 | 0.95 (1.94) | −0.46 (1.42) | −3.56; 4.62 |
| Philippines | National | 2017 | 10247 | 0.88 | 0.52 (1.22) | −1.44 (1.17) | −2.33; 3.09 |
| Sri Lanka | National | 2015 | 3000 | 0.88 | 0.17 (0.76) | −1.11 (0.97) | −1.77; 2.17 |
| Tajikistan | National (brief MDS) | 2018 | 2992 | 0.83 | 0.26 (0.97) | −1.59 (1.21) | −1.31; 1.81 |