Evaluation of diagnostic tests for infectious diseases: general principles

Banoo, Shabir; Bell, David; Bossuyt, Patrick M.; Herring, A. J.; Mabey, David; Poole, Freddie; Smith, Peter G.; Sriram, N.; Wongsrichanalai, Chansuda; Linke, Ralf D.; O’Brien, Rick; Perkins, Mark D.; Cunningham, Jane; Matsoso, Precious; Nathanson, Carl Michael; Olliaro, Piero; Peeling, Rosanna W.; Ramsay, Andy

doi:10.1038/nrmicro1523y

Cited by 129 publications

(154 citation statements)

References 11 publications

Supporting

Mentioning

148

Contrasting

Unclassified

Order By: Relevance

“…30 Assuming a prevalence of impending water-loss dehydration (plasma osmolality !295 mOsm/kg) of 17%, 7 and allowing for an approximate onethird exclusion rate from data analysis (because of missing reference tests, and comorbidities that preclude the use of the reference standards), a total of 178 participants were recruited into the study. Medical records for participants were accessed after enrollment and because of potential influencing effects on the reference standards assessed in this study, participants with a history of renal disease (chronic kidney disease stage 1e5, n ¼ 24), or who were in cardiac failure as diagnosed by a clinician (n ¼ 1) were excluded from data analysis.…”

Section: Sample Size Calculation and Data Analysismentioning

confidence: 99%

Is This Elderly Patient Dehydrated? Diagnostic Accuracy of Hydration Assessment Using Physical Signs, Urine, and Saliva Markers

Fortes

Owen

Raymond-Barker

et al. 2015

Journal of the American Medical Directors Association

128

102

View full text Add to dashboard Cite

Objectives: Dehydration in older adults contributes to increased morbidity and mortality during hospitalization. As such, early diagnosis of dehydration may improve patient outcome and reduce the burden on healthcare. This prospective study investigated the diagnostic accuracy of routinely used physical signs, and non-invasive markers of hydration in urine and saliva. Design: Prospective diagnostic accuracy study. Setting: Hospital acute medical care unit and emergency department. Participants: One hundred and thirty older adults (59 males, 71 females, mean (SD) age = 78 (9) y). Measurements: Participants with any primary diagnosis underwent a hydration assessment within 30min of admittance to hospital. Hydration assessment comprised seven physical signs of dehydration (tachycardia (>100bpm), low systolic blood pressure (<100mmHg), dry mucous membrane, dry axilla, poor skin turgor, sunken eyes, and long capillary refill time (>2s)), urine color, urine specific gravity (USG), saliva flow rate (SFR) and saliva osmolality. Plasma osmolality (Posm) and the blood urea nitrogen to creatinine ratio (BUN:Cr) were assessed as reference standards of hydration, with 21% of participants classified with water-loss dehydration (Posm >295mOsm/kg), 19% classified with water-and-solute-loss dehydration (BUN:Cr >20) and 60% classified as euhydrated. Results: All physical signs showed poor sensitivity (0-44%) for detecting either form of dehydration, with only low systolic blood pressure demonstrating potential utility for aiding the diagnosis of water-and-solute-loss dehydration (diagnostic OR = 14.7). Neither urine color, USG, nor SFR could discriminate hydration status (area under the receiver operating characteristic curve, AUCROC = 0.49-0.57, P>0.05). In contrast, saliva osmolality demonstrated moderate diagnostic accuracy (AUCROC = 0.76, P<0.001) to distinguish both dehydration types (70% sensitivity, 68% specificity, OR =5.0 (95%CI 1.7-15.1) for water-loss dehydration, and 78% sensitivity, 72% specificity, OR =8.9 (95%CI 2.5-30.7) for water-and-solute-loss dehydration). Conclusions: With the exception of low systolic blood pressure, which could aid in the specific diagnosis of water-and-solute-loss dehydration, physical signs and urine markers show little utility to determine if an elderly patient is dehydrated. Saliva osmolality demonstrated superior diagnostic accuracy compared with physical signs and urine markers, and may have utility for the assessment of both water-loss and water-andsolute-loss dehydration in older individuals. It is particularly noteworthy that saliva osmolality was able to detect water-and-solute-loss dehydration, for which a measurement of plasma osmolality would have no diagnostic utility. Thankyou for allowing us to resubmit the above manuscript to your journal. We have responded to the reviewers comments (see below), with changes in the manuscript highlighted in red text. We hope you feel that these changes have improved the manuscript.Please don't hesitate to contact me if you require...

show abstract

Section: Sample Size Calculation and Data Analysismentioning

confidence: 99%

Is This Elderly Patient Dehydrated? Diagnostic Accuracy of Hydration Assessment Using Physical Signs, Urine, and Saliva Markers

Fortes

Owen

Raymond-Barker

et al. 2015

Journal of the American Medical Directors Association

128

102

View full text Add to dashboard Cite

show abstract

“…Sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) are recommended indicators that evaluate diagnostic performance [1]. The PPV and the NPV are particularly interesting in case of low disease prevalence [2]; however, they rely on the choice of a threshold biomarker value that classifies the subjects into diseased and nondiseased.…”

Section: Introductionmentioning

confidence: 99%

The precision–recall curve overcame the optimism of the receiver operating characteristic curve in rare diseases

Ozenne¹,

Subtil²,

Maucort-Boulch³

2015

Journal of Clinical Epidemiology

268

180

View full text Add to dashboard Cite

“…J indices have possible values between 0 and 1, and as values approach 1, the overall diagnostic ability approaches the ideal. Also, 95% confidence intervals (95% CI) for sensitivity and specificity were calculated from previous report (Banoo et al 2006). a Two samples (1,600 and 4,000 parasites/μl, respectively) were determined to be negative and is also negative by LAMP b Four samples were determined to be negative and two samples (3,375 and 1,737 parasites/μl, respectively) were positive by nested PCR…”

Section: Statisticsmentioning

confidence: 99%

“…The most common malaria diagnosis method is the microscopic examination of blood smears, and it has traditionally been considered as the gold standard test for malaria diagnosis (Moody 2002;Banoo et al 2006). Now, a variety of diagnostic methods for malaria are available, such as antigen detection (Lee et al 2002), fluorescence-based assays (Makler et al 1998), and PCR (Snounou et al 1993).…”

Section: Introductionmentioning

confidence: 99%

Molecular test for vivax malaria with loop-mediated isothermal amplification method in central China

Gao

Zhou

et al. 2011

Parasitol Res

View full text Add to dashboard Cite

Vivax malaria has the highest incidence in central China. High-throughput and cost-effective testing methods are essential for vivax malaria diagnosis in this area. Loop-mediated isothermal amplification (LAMP) is an established nucleic acid amplification method, which provides a promising platform for the molecular detection of malaria parasites in development countries. This study was performed to compare the LAMP method, the nested PCR-based method, and microscopic examinations in diagnosing vivax malaria. LAMP detected vivax malaria parasites in 160 of 164 microscopically positive samples (sensitivity, 97.6%), whereas nested PCR detected Plasmodium vivax in 162 of 164 samples (sensitivity, 98.8%). No false-positive results were obtained by LAMP or nested PCR among fever-positive and healthy samples. The sensitivities and specificities of the two molecular tests were consistently high. In addition, the reproducibility of the LAMP assays using water bath, which reduced the cost substantially. LAMP method is an accurate, rapid, simple, and cost-effective method that may be useful for diagnosis in field diagnoses instead of nested PCR. This method is feasible to diagnose vivax malaria parasite in endemic areas of central China.

show abstract

Evaluation of diagnostic tests for infectious diseases: general principles

Cited by 129 publications

References 11 publications

Is This Elderly Patient Dehydrated? Diagnostic Accuracy of Hydration Assessment Using Physical Signs, Urine, and Saliva Markers

Is This Elderly Patient Dehydrated? Diagnostic Accuracy of Hydration Assessment Using Physical Signs, Urine, and Saliva Markers

The precision–recall curve overcame the optimism of the receiver operating characteristic curve in rare diseases

Molecular test for vivax malaria with loop-mediated isothermal amplification method in central China

Contact Info

Product

Resources

About