Clean or Not to Clean: A Comparison of Urine Collection Techniques

Purpose:

The purpose of this study was to compare the validity of urine collection between clean-catch midstream technique and non-cleansing midstream technique in females.

 

Methods:

Meta-analyses were conducted to compare urine contamination rates between samples collected from females by using clean-catch midstream technique (CCMS) and non-cleansing midstream technique (NCMS). Four English and one Chinese electronic databases were used to search literature up to June , 2013. MeSH terms ‘urine specimen collection’ and ‘urine collection’ were used to search published studies. References addressed in included studies were also screened. Studies that provided comparisons on urine sample contamination rates between NCMS and CCMS were included. To promote validity of data abstraction, data were extracted by two researchers independently. Disagreement on data abstraction was resolved by complete consensus between researchers. Study quality was evaluated by the Johns Hopkins Nursing Evidence-based Practice Quality Rating Scale. Data analysis was performed by using the random effect model.

Results:

Six studies that provided seven comparisons were identified from 2812 citations.The total subjects involved were 1181 patients. Four studies were conducted in the United States, and two studies were conducted in the England. Two studies used a single group pre-post design; four studies applied a two group experimental design. Only two studies randomized study subjects into groups. Study qualities of included studies ranged from Ib to IIc. The result of meta-analysis on two studies with one group pre-post design suggested no difference in contamination rates of urine samples collected by either NCMS or CCMS techniques (OR=.962, p=.608). The meta-analysis of four studies with two independent groups also presented a similar result (OR=.892, p=.638).

Conclusion:

The CCMS technique was recommended since early 1950s. It is also a practice standard recommended by many authorities. However, the CCMS requires a time-consuming instruction, and is frequently performed not correctly. It is also costly for supplies. This meta-analysis study suggested that results of current urine collection studies consistently supported no variation in validity between NCMS and CCMS techniques. Because of lower study quality of included studies, this study encouraged more high quality studies to be conducted before having the NCMS technique as the clinical practice guideline for urine collection.