Table 5

Clinical presentation: diagnostic accuracy, sensitivity, specificity, positive and negative likelihood ratios (95% CI), χ² and p value

N	Test	True +ve	False +ve	False −ve	True –ve	Diagnostic accuracy (%)†	Sensitivity	Specificity	LR+	LR−	χ²	p Value
84	Pain out of proportion to the apparent injury	24	10	13	37	72.6	0.65 (0.49 to 0.78)	0.79 (0.65 to 0.88)	3.05 (1.68 to 5.55)	0.45 (0.28 to 0.71)	14.57	0.00*
83	Pain felt in the shank or the knee during injury	18	14	18	33	61.4	0.50 (0.34 to 0.66)	0.70 (0.56 to 0.81)	1.68 (0.97 to 2.90)	0.71 (0.49 to 1.04)	2.71	0.10
87	Inability to hop	34	35	4	14	55.2	0.89 (0.76 to 0.96)	0.29 (0.18 to 0.42)	1.25 (1.02 to 1.54)	0.37 (0.13 to 1.03)	3.22	0.07
82	Mechanism of injury‡	30	36	6	10	48.8	0.83 (0.68 to 0.92)	0.22 (0.12 to 0.36)	1.07 (0.87 to 1.32)	0.77 (0.31 to 1.91)	0.09	0.77
86	Inability to walk	34	38	4	10	51.2	0.89 (0.76 to 0.96)	0.21 (0.12 to 0.34)	1.13 (0.94 to 1.36)	0.51 (0.17 to 1.49)	0.98	0.32
84	Swelling at or above the anterior inferior tibiofibular ligament	17	28	19	20	44.0	0.47 (0.32 to 0.63)	0.42 (0.29 to 0.56)	0.81 (0.53 to 1.23)	1.27 (0.80 to 2.00)	0.62	0.43
86	Local tenderness deltoid ligament	16	32	21	17	38.4	0.43 (0.29 to 0.59)	0.35 (0.23 to 0.49)	0.66 (0.43 to 1.01)	1.64 (1.02 to 2.63)	3.31	0.07
60	Lunge and twist	13	23	11	13	43.3	0.54 (0.35 to 0.72)	0.36 (0.22 to 0.52)	0.85 (0.55 to 1.32)	1.27 (0.69 to 2.35)	0.23	0.63
59	Posterior impingement	14	17	10	18	54.2	0.58 (0.39 to 0.76)	0.51 (0.36 to 0.67)	1.20 (0.74 to 1.94)	0.81 (0.46 to 1.44)	0.22	0.64

*Significant at p≤0.05 level.
†(true positive+true negative)/number of cases, as described by Portney and Watkins.42
‡Mechanism of dorsiflexion and/or external rotation.
+ve, positive; −ve, negative.
LR, likelihood ratio.