Table 4.

Contamination rates in each culture system for different clinical materials from patients without cystic fibrosis

Clinical materialNo. of specimens (% of total)% Contamination ina:Pc
460960LJ460 vs 960460 vs LJ960 vs LJ
Respiratory1,218 (51.1)3.26.44.2<0.001NS0.015
Sterile body site specimen444 (18.6)0.50.70.2NSNSNS
Urine319 (13.4)4.49.17.20.018NSNS
Gastrointestinal tract251 (10.5)8.421.519.5<0.001<0.001NS
 Gastric aspirate189 (7.9)8.522.222.20.002 0.002NS
 Stool40 (1.7)12.530.015.0NSNSNS
Otherb 150 (6.3)1.30.72.0NSNSNS
Total2,382 (100.0)3.36.95.3<0.001<0.0010.021
  • a Abbreviations: 460, BACTEC 460TB system; 960, BACTEC MGIT 960 system; LJ, LJ medium. For differences between material groups, P < 0.001 .

  • b Includes specimens other than those mentioned in the table.

  • c Abbreviations: NS, not significant.