[Is the technique used to collect urine important in avoiding contamination of samples?].
OBJECTIVE
To appraise the efficacy of hygienic standards in preventing the contamination of urine samples.


METHODS
Randomised clinical trial. 515 women assigned at random: 279 to the Intervention group and 236 to Control.


METHODS
Population registered with 4 doctors at 2 health centres.


METHODS
Women from 15 to 65 who attended the clinic for on-demand care. Criteria for exclusion from the trial were: permanent bladder catheter, anomalies in genito-urinary apparatus, antibiotic treatment in the 7 previous days and inability to understand instructions.


METHODS
Verbal instructions on hygienic standards for collecting the sample and explanatory leaflet, as against the customary guidelines.


METHODS
The main result was the combination of contamination levels and infection. Analysis by intention to treat.


RESULTS
Irregularities in the urine culture in 113 (41%) patients from the Intervention group and in 133 (56%) from the Control group (P<.001), with RRR of 28% (95% CI, 14%-40%) and NNT of 6 (95% CI, 4-14). Taking only serious contamination or urinary infection, we had 14 in the Intervention group and 36 in the Control (P<.0001), with RRR of 67% (95% CI, 41%-82%) and NNT of 10 (95% CI, 6-20).


CONCLUSIONS
Providing an explanatory leaflet and giving verbal instructions on hygienic standards for urine collection reduces contamination of the samples.
Cabedo García
V R
VR
Médico de Familia, Centro de Salud El Barranquet, Larga 70, 12005 Castellón, Spain. vcabedog@meditex.es
Novoa Gómez
C
C
Tirado Balaguer
M D
MD
Rodríguez Morquecho
N
N
Rodríguez Bailo
M T
MT
Solá Sandtner
A
A
D000293:Adolescent; D000328:Adult; D000368:Aged; D005260:Female; D006801:Humans; D008875:Middle Aged; D010353:Patient Education as Topic; D012307:Risk Factors; D013048:Specimen Handling / Q000379:methods*; D016482:Urinalysis / Q000379:methods*; D014552:Urinary Tract Infections / Q000175:diagnosis*