Table 4

Performance of SILS at a threshold of 2 (N = 999)*

Characteristic
Impairedand Inadequate Reading Ability (S-TOFHLA < 16)
Impairedand Limited Reading Ability (S-TOFHLA < 23)

Sensitivity (%)
67 (58, 76)
54 (47, 61)
Specificity (%)
82 (80, 85)
83 (81, 86)
Positive Predictive Power
0.31 (0.25, 0.37)
0.40 (0.34, 0.47)
Negative Predictive Power
0.96 (0.94, 0.97)
0.90 (0.88, 0.92)
Likelihood Ratio Positive (LR +)
3.79 (3.12, 4.6)
3.28 (2.67, 4.03)
Likelihood Ratio Negative (LR -)
0.40 (0.30, 0.53)
0.55 (0.47, 0.65)
Area under the ROC curve
0.78 (0.73,0.83)
0.73 (0.69, 0.78)

**Main analysis is based on S-TOFHLA < 23.

Impaired = Low vision or physically unable to complete the S-TOFHLA.

Results are point estimates and 95% confidence intervals.

Morris et al. BMC Family Practice 2006 7:21   doi:10.1186/1471-2296-7-21