Evidence-Based Cutoff Threshold Values from Receiver Operating Characteristic Curve Analysis for Knee Osteoarthritis in the 50-Year-Old Korean Population: Analysis of Big Data from the National Health Insurance Sharing Service

Table 3

Logistic regression and ROC curve analyses for patients with OA.

Parameter	OR	AUC	value	Cutoff values	Sensitivity (%)	Specificity (%)
Sex	1.973	0.559	<0.01	N/A	N/A	N/A
Age (years)	0.895	0.265	<0.01	N/A	N/A	N/A
SGOT_AST (U/L)	1.014	0.463	<0.01	18.75	88%	85%
ELD_STF_SEC (s)	0.189	0.022	<0.01	14.75	75%	100%
Fall	0.963	0.895	<0.01	N/A	N/A	N/A
ELD_LLFX_SEC (s)	0.478	0.861	<0.01	8.25	80%	100%

Variables with significant values were selected via logistic regression analysis, and then other factors such as AUC, value, and sensitivity and specificity of the cutoff points were considered to finally select the cutoff threshold values of the significant variables. ROC, receiver operating characteristic; OA, osteoarthritis; OR, odds ratio; AUC, area under the curve; N/A, not applicable; SGOT_AST, serum glutamic oxaloacetic transaminase and aspartate aminotransferase; ELD_STF_SEC, standing time on one leg in seconds; ELD_LLFX_SEC, time in seconds from standing up from a chair to walking 3 m and returning to the same chair.