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PubMed · 7703614

The chi-square test.

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M Pagano. The chi-square test.. https://pubmed.ncbi.nlm.nih.gov/7703614/

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Successful use of genotypic resistance testing in HIV-1-infected individuals with detectable viraemia between 50 and 1000 copies/ml.

Traditionally an HIV viral load of over 1000 copies/ml was presumed necessary for genotypic resistance testing. We performed a retrospective analysis to assess rates of viral amplification on viral loads between 50 and 1000 copies/ml. Amplification was significantly more likely for 200-1000 copies/ml than 50-200 copies/ml; most samples amplified successfully, supporting the use of genotyping for low-level viraemia.

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Computerised pathology test order entry reduces laboratory turnaround times and influences tests ordered by hospital clinicians: a controlled before and after study.

OBJECTIVE: To assess the impact of a computerised pathology order entry system on laboratory turnaround times and test ordering within a teaching hospital. METHODS: A controlled before and after study compared test assays ordered from 11 wards two months before (n = 97 851) and after (n = 113 762) the implementation of a computerised pathology order entry system (Cerner Millennium Powerchart). Comparisons were made of laboratory turnaround times, frequency of tests ordered and specimens taken, proportions of patients having tests, average number per patient, and percentage of gentamicin and vancomycin specimens labelled as random. RESULTS: Intervention wards experienced an average decrease in turnaround of 15.5 minutes/test assay (range 73.8 to 58.3 minutes; p<0.001). Reductions were significant for prioritised and non-prioritised tests, and for those done within and outside business hours. There was no significant change in the average number of tests (p = 0.228), or specimens per patient (p = 0.324), and no change in turnaround time for the control ward (p = 0.218). Use of structured order screens enhanced data provided to laboratories. Removing three test assays from the liver function order set resulted in significantly fewer of these tests being done. CONCLUSIONS: Computerised order entry systems are an important element in achieving faster test results. These systems can influence test ordering patterns through structured order screens, manipulation of order sets, and analysis of real time data to assess the impact of such changes, not possible with paper based systems. The extent to which improvements translate into improved patient outcomes remains to be determined. A potentially limiting factor is clinicians' capacity to respond to, and make use of, faster test results.

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Oral care reduces incidence of ventilator-associated pneumonia in ICU populations.

OBJECTIVE: To examine whether oral care contributes to preventing ventilator-associated pneumonia (VAP) in ICU patients. DESIGN: Nonrandomized trial with historical controls. SETTING: A medical-surgical ICU in a university hospital. PATIENTS: 1,666 mechanically ventilated patients admitted to the ICU. INTERVENTION: Oral care was provided to 1,252 patients who were admitted to the ICU during period between January 1997 and December 2002 (oral care group), while 414 patients who were admitted to the ICU during period between January 1995 and December 1996 and who did not receive oral care served as historical controls (non-oral care group). MEASUREMENTS AND RESULTS: Incidence of VAP(episodes of pneumonia per 1000 ventilator days) in the oral care group was significantly lower than that in the non-oral care group (3.9 vs 10.4). The relative risk of VAP in the oral care group compared to that in the non-oral care group was 0.37, with an attributable risk of -3.96%. Furthermore, length of stay in ICU before onset of VAP was greater in the oral care than in the non-oral care group (8.5+/-4.6 vs 6.3+/-7.5 days). However, no significant difference was observed in either duration of mechanical ventilation or length of stay between the groups (5.9+/-10.8 vs 6.0+/-8.8 days and 7.5+/-11.5 vs 7.2+/-9.5 days, respectively). Pseudomonoas aeruginosa was the most frequently detected bacteria in both groups. Number of potentially pathogenic bacteria in oral cavity was significantly reduced by single oral care procedure. CONCLUSION: Oral care decreased the incidence of VAP in ICU patients. DESCRIPTOR: Pulmonary nosocomial infection.

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