Purpose: Urine dipstick is a commonly used test for detecting urinary tract infections because of its rapidity and low cost. Urine culture is the traditional golden standard for detecting urinary tract infection diagnosis. 

In comparison to the golden standard, urine culture, this paper investigates whether the use of a urine dipstick is a valid method to identify the presence of bacteria in urine and thereby diagnose it as a urinary tract infection, in a Danish context, where the definition of a positive urine culture is 104 CFU/ml (10,000) bacteria in the urine.

This study is performed by testing sensitivity and specificity in dipsticks and by sending urine for culture.

Results: The study included 65 patients with hip fractures. ROC curves gave an AUC value of 0.72 (95% confidence interval [CI], 0.630–0.825). ROC was used to measure positive urine sticks.

There were 26 true positive and 22 false positive dipsticks in total. The sensitivity of the urine cultures was a total of 66.6. There is significant uncertainty about whether dipsticks can identify urinary tract infections, as the results were between 0.49 and 0.80. The specificity in our study was 78.8 in total. The accuracy was 75.5. 

The confidence interval at 95% for the true positive dipstick was between 0.39 and 0.68. The false positive was between 0.31 and 0.60. The true negative tests showed results between 0.77 and 0.92. The false negative result was between 0.07 and 0.22. 

Conclusion: The sensitivity and specificity of the urine dipstick to identify bacteriuria were 0.66 and 0.78, respectively, meaning that bacteriuria was overlooked in one-third of the tested urine. However, the combination of nitrite and leucocyte esterase in testing correctly excluded bacteriuria in 86% of the tests.