An evaluation of the clinical features of measles virus infection for diagnosis in children within a limited resources setting

Abstract Background Measles is a recurrent health problem in both advanced and developed countries. The World Health Organization (WHO) recommends anti-measles immunoglobulin M (Ig M) as the standard method of detecting the virus; however, many areas still present the inability to perform a serology test of anti-measles IgM. Therefore, a typical clinical feature is necessary to establish the diagnosis of measles. The objective of this study was to evaluate hyperpigmented rash and other clinical features as the diagnostic tools with respect to measles, especially in an outbreak setting. Methods In this observational diagnostic study, the inclusion criteria were as follows: between 6 and 144 months of age, fever, maculopapular rash for 3 days or more, accompanied by a cough, or coryza, or conjunctivitis. Those with a prior history of measles vaccination (1–6 weeks) were excluded, in addition to those with histories of corticosteroid for 2 weeks or more and immunocompromised conditions. The samples were taken from Dr. Soetomo General Academic Hospital in Surabaya, Indonesia. We evaluated the sensitivity, specificity, the positive predictive value, and the negative predictive value of such clinical features. Hyperpigmented rash was validated using Kappa and Mc Nemar tests. Anti-measles Ig M was considered as the gold standard. Results This study gathered 82 participants. The clinical manifestations of all subjects included fever, cough, coryza, conjunctivitis, Koplik spots, and maculopapular rash (which turns into hyperpigmented rash along the course of the illness). Most maculopapular rashes turn out to be hyperpigmented (89%). Sensitivity, specificity, positive predictive value, and negative predictive values of the combination of fever, maculopapular rash, and hyperpigmented rash were found to be at 90.7, 28.6, 93.2, and 22.2%, respectively. The Mc Nemar and Kappa tests showed p values of 0.774 and 0.119, respectively. Conclusion The combination of fever, maculopapular rash, and hyperpigmented rash can be used as a screening tool regarding measles infection in an outbreak setting, which can then be confirmed by anti-measles Ig M. Cough, coryza, and Koplik’s spot can be added to this combination, albeit with a slight reduction of sensitivity value.

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Foundational Statistical Principles in Medical Research: Sensitivity, Specificity, Positive Predictive Value, and Negative Predictive Value

Medicina ◽

10.3390/medicina57050503 ◽

2021 ◽

Vol 57 (5) ◽

pp. 503

Author(s):

Thomas F. Monaghan ◽

Syed N. Rahman ◽

Christina W. Agudelo ◽

Alan J. Wein ◽

Jason M. Lazar ◽

...

Keyword(s):

Positive Predictive Value ◽

Negative Predictive Value ◽

Predictive Value ◽

Medical Literature ◽

Disease Prevalence ◽

Positive Test Result ◽

Predictive Values ◽

Sensitivity Specificity ◽

Test Result ◽

Test Probability

Sensitivity, which denotes the proportion of subjects correctly given a positive assignment out of all subjects who are actually positive for the outcome, indicates how well a test can classify subjects who truly have the outcome of interest. Specificity, which denotes the proportion of subjects correctly given a negative assignment out of all subjects who are actually negative for the outcome, indicates how well a test can classify subjects who truly do not have the outcome of interest. Positive predictive value reflects the proportion of subjects with a positive test result who truly have the outcome of interest. Negative predictive value reflects the proportion of subjects with a negative test result who truly do not have the outcome of interest. Sensitivity and specificity are inversely related, wherein one increases as the other decreases, but are generally considered stable for a given test, whereas positive and negative predictive values do inherently vary with pre-test probability (e.g., changes in population disease prevalence). This article will further detail the concepts of sensitivity, specificity, and predictive values using a recent real-world example from the medical literature.

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DIAGNOSTIC ACCURACY OF GRAY SCALE ULTRASONOGRAPHY VERSUS COLOR DOPPLER IN SUSPECTED CASES OF ACUTE APPENDICITIS

The International Journal of Frontier Sciences ◽

10.37978/tijfs.v5i1.319 ◽

2021 ◽

Vol 5 (1) ◽

Author(s):

Tahir Iqbal ◽

Muhammad Usman Shahid ◽

Ishfaq Ahmad Shad ◽

Shahzad Karim Bhatti ◽

Syed Amir Gilani ◽

...

Keyword(s):

Acute Appendicitis ◽

Positive Predictive Value ◽

Diagnostic Accuracy ◽

Negative Predictive Value ◽

Predictive Value ◽

Color Doppler ◽

Diagnostic Tools ◽

Gray Scale ◽

Versus Color ◽

Sensitivity Specificity

ABSTRACT: BACKGROUND: A common surgical emergency is acute appendicitis. Various diagnostic tools are available to diagnosis acute appendicitis. Radiological investigations play an important role in making accurate and early diagnosis and thus preventing morbidity associated with the disease. OBJECTIVE: To determine the diagnostic accuracy of gray scale ultrasonography versus color Doppler in suspected cases of acute appendicitis. MATERIALS AND METHODS: The study was carried in the department of Radiology of Mayo Hospital, Lahore. A total of 75 patients were enrolled of age 18-40 years, both genders who were suspected cases of acute appendicitis. All patients underwent baseline investigations along with gray scale ultrasonography and color Doppler. All patients were subjected to surgery to confirm the diagnosis and findings were subjected to statistical analysis. RESULTS: The mean age of the patients was 23.25 ±10.55 and mean transverse diameter of appendix was 8.37 ±3.39. There were 62.7% males and 37.3%females. Findings of gray scale ultrasonography and color Doppler were then correlated with surgical findings to calculate the diagnostic accuracy of these modalities. The results revealed that gray scale ultrasonography sensitivity, specificity, positive predictive value, negative predictive value and accuracy was 92.7%, 94.32%, 95%, 91.4% and 93.3% respectively, whereas color Doppler had sensitivity, specificity, positive predictive value, negative predictive value and accuracy of 97.7%, 93.9%, 95.3%, 97% and 96% respectively. Diagnostic accuracy of both modalities together was 98.6%. CONCLUSION: Color Doppler has better diagnostic accuracy than gray scale ultrasonography for diagnosis of acute appendicitis and the combination of both modalities yields diagnostic accuracy that is similar to gold standard.

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Clinical Performance of the Spot Vision Photo Screener before and after Induction of Cycloplegia in Children

Journal of Ophthalmology ◽

10.1155/2019/5329121 ◽

2019 ◽

Vol 2019 ◽

pp. 1-7 ◽

Cited By ~ 1

Author(s):

Konuralp Yakar

Keyword(s):

Positive Predictive Value ◽

Negative Predictive Value ◽

Predictive Value ◽

Clinical Performance ◽

High Specificity ◽

Screening Criteria ◽

Predictive Values ◽

Before And After ◽

Sensitivity Specificity ◽

Vision Screener

Aim. To compare the clinical performance of the Spot Vision Screener used to detect amblyopia risk factors (ARFs) in children before and after induction of cycloplegia; the children were referred because they met the screening criteria of the American Association for Pediatric Ophthalmology and Strabismus (AAPOS). Methods. The Spot Vision Screener and a standard autorefractometer were used to examine 200 eyes of 100 children aged 3–10 years, before and after cycloplegia induction, in terms of ARFs. Sensitivity, specificity, and positive and negative predictive values for the detection of significant refractive errors were measured using the AAPOS referral criteria. It was explored that Spot Screener data were affected by cycloplegia. The extent of agreement between cycloplegic/noncycloplegic photoscreening data and cycloplegic autorefraction measurements was assessed using Wilcoxon and Spearman correlation analyses. Results. The Spot’s sensitivity was improved from 60.9% to 85.3% and specificity from 94.9% to 87.4% with cycloplegia compared to cycloplegic standard autorefractometer results. The positive predictive value of Spot was 75.7%, and the negative predictive value was 90.4% without cycloplegia. With cycloplegia, the positive predictive value of Spot was 63.6% and the negative predictive value was 95.8%. Conclusions. The Spot Screener afforded moderate sensitivity and high specificity prior to cycloplegia. The sensitivity and negative predictive value improved after induction of cycloplegia. Examiners should be aware of the effects of cycloplegia on their findings.

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Sensitivity, Specificity and Predictive Values of Cytological and Microbiological Findings of Endometrial Biopsy, Cytobrush and Low Volume Uterine Lavage in Relation to Endometrial Histology in Barren Mares

THE INDIAN JOURNAL OF VETERINARY SCIENCES AND BIOTECHNOLOGY ◽

10.21887/ijvsbt.15.4.16 ◽

2020 ◽

Vol 15 (04) ◽

pp. 75-79

Author(s):

Agnus Mathew ◽

DM Patel ◽

KK Hadiya

Keyword(s):

Positive Predictive Value ◽

Negative Predictive Value ◽

Predictive Value ◽

Endometrial Biopsy ◽

Microbial Culture ◽

K Value ◽

Predictive Values ◽

Low Volume ◽

Sensitivity Specificity ◽

Uterine Lavage

This study was carried out on 10 infertile barren mares to evaluate the sensitivity, specificity, predictive values and agreement (kappa value) of cytological and microbiological findings of three diagnosing techniques of endometritis, viz., endometrial biopsy (EB), cytobrush (CB) and low volume uterine lavage (LVL) in relation to endometrial histology. When histological examinations from EB were used as “the best standard,” the sensitivity of cytology from EB, CB and LVL technique was 0.33, 0.50 and 0.50; specificity 0.75, 1.00 and 0.75; positive predictive value 0.66, 1.00 and 0.75, and negative predictive value was 0.42, 0.57 and 0.50, respectively. The sensitivity of bacteriology from EB, CB and LVL technique was 0.83, 0.83 and 1.00; the specificity was 0.75, 0.75 and 0.50; positive predictive value 0.83, 0.83 and 0.75, and the negative predictive value was 0.75, 0.75 and 1.00, respectively. In all the cases, the sensitivity of the bacteriology was found to be higher than the sensitivity of cytology. When the results of cytological and bacteriological examinations were combined, no any increase in the sensitivity was found. Bacteriology and cytology from CB showed the highest positive predictive value demonstrating that a positive result is an accurate indication of endometritis. Sensitivity values were always higher if smears were evaluated according to PMNs to epithelial cell ratio, and the highest values were observed in specimens collected from CB and LVL. The evaluation of cytological smears based on counting PMNs in relation to epithelial cells was a better method for diagnosis of endometritis than counting the number of PMNs per high power microscopic field (k value 0.07-0.47 vs. 0.00). The agreement of the diagnosis of endometritis between the three techniques of the collection was from fair to poor and between the different criteria adopted to evaluate smears was always poor. However, the agreement of the diagnosis of endometritis by the microbial culture was moderate between the three techniques of the collection (k value 0.55-0.58).

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Three Questions to Screen your Patients for Chemical, Food, and Drug Intolerances the Brief Environmental Exposure and Sensitivity Inventory (BREESI)

10.21203/rs.2.20539/v1 ◽

2020 ◽

Author(s):

Raymond F Palmer ◽

Carlos Roberto Jaén ◽

Roger B. Perales ◽

Rodolfo Rincon ◽

Jacqueline Viramontes ◽

...

Keyword(s):

Primary Care ◽

Positive Predictive Value ◽

Environmental Exposure ◽

Health Care Professionals ◽

Predictive Value ◽

Primary Care Clinic ◽

Diagnostic Tools ◽

Care Clinic ◽

Predictive Values ◽

Chemical Intolerance

Abstract Background: The 50-item Quick Environmental Exposure and Sensitivity Inventory (QEESI) is a validated questionnaire used worldwide to assess intolerances to chemicals, foods, and/or drugs and has become the gold standard for assessing chemical intolerance (CI). Despite a reported prevalence of 8-33%, CI often goes undiagnosed in epidemiological studies and routine primary care. To enhance the QEESI’s utility, we developed the Brief Environmental Exposure and Sensitivity Inventory (BREESI) as a 3-item CI screening instrument. We tested the BREESI’s potential to predict whether an individual is likely to respond adversely to structurally unrelated chemicals, foods, and drugs. Methods: We recruited 286 adult participants from a university-based primary care clinic and through online participation. The positive and negative predictive values of the BREESI items were calculated against the full QEESI scores. Results: 90% of participants answering “yes” to all three items on the BREESI were classified as very suggestive of CI based upon the QEESI chemical intolerance and symptom scores both ≥ 40 (positive predictive value = 90%). For participants endorsing two items, 92% were classified as either very suggestive (39%) or Suggestive (53%) of CI (positive predictive value = 87%). Of those endorsing only one item, only 13% were found to be very suggestive of CI. However, 70% were classified as Suggestive. Of those answering “No” to all of the BREESI items, 99% were classified as not suggestive of CI (i.e., negative predictive value = 99%). Conclusions: The BREESI is a versatile screening tool for rapidly determining potential CI, with clinical and epidemiological applications. Together, the validated BREESI and QEESI provide much needed diagnostic tools that will help inform treatment protocols and teach health care professionals about Toxicant Induced Loss of Tolerance – the mechanism driving CI.

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TP8.1.12 Diagnostic Utility of MRI in the Evaluation of Potential Malignancy in Patients Presented with Nipple Discharge

British Journal of Surgery ◽

10.1093/bjs/znab362.074 ◽

2021 ◽

Vol 108 (Supplement_7) ◽

Author(s):

Nixon Phua Cher Yang ◽

Muhammad Adeel Javed Butt ◽

Parmvir Singh Nijjar ◽

Saung Phyu ◽

Musa Barkeji

Keyword(s):

Positive Predictive Value ◽

Predictive Value ◽

Ductal Carcinoma ◽

Nipple Discharge ◽

Diagnostic Value ◽

Predictive Values ◽

Imaging Tool ◽

Additional Imaging ◽

Magnetic Resonance Imaging Mri ◽

Sensitivity Specificity

Abstract Aims Nipple discharge is a presentation commonly seen at breast clinics. It is conventionally evaluated with physical examination and sonography( or mammography). The aim of this study is to investigate the diagnostic value of magnetic resonance imaging (MRI) as an additional imaging tool in the evaluation of potential malignancy in patients presented with nipple discharge. Methods A retrospective evaluation of 85 patients with nipple discharge who underwent breast ultrasound (USS) and MRI between 04/06/2008 and 25/10/2019 was conducted. Clinical notes, radiographic reports and biopsy results were reviewed. Sensitivity, specificity, positive predictive value and negative predictive value of USS and MRI were calculated. Results Out of the 85 patients (all female; mean age 45.33 +/- 12.93 years old) with nipple discharge, 11 were found to have biopsy-proven malignancy (invasive ductal carcinoma/ ductal carcinoma in situ; 12.94% risk). USS failed to identify seven malignancies (27.27% sensitivity) while MRI missed three malignancies (72.72% sensitivity). USS falsely identified four malignancies from 74 patients with no malignancy (94.59% specificity) while MRI only falsely identified one case (98.65% specificity). For patients with negative USS results (U1/U2/U3) or negative MRI results (BI-RADS category 1,2 or 3), the negative predictive values of USS is 89.74% while that of MRI is 96.05%. The positive predictive values of USS and MRI are 42.86% and 88.88% respectively. Conclusion Compared to USS, MRI has a higher sensitivity, specificity, positive predictive value and predictive value. It will be a valuable addition to the standard nipple discharge evaluation workup to help rule out malignancy.

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A comparative study of RIPASA score and ALVARADO score in diagnosis of acute appendicitis

International Surgery Journal ◽

10.18203/2349-2902.isj20180430 ◽

2018 ◽

Vol 5 (3) ◽

pp. 796

Author(s):

Vamsavardhan Pasumarthi ◽

C. P. Madhu

Keyword(s):

Acute Appendicitis ◽

Positive Predictive Value ◽

Diagnostic Accuracy ◽

Roc Curve ◽

Predictive Value ◽

Scoring System ◽

Alvarado Score ◽

Predictive Values ◽

Sensitivity Specificity ◽

Ripasa Score

Background: The RIPASA Score is a new diagnostic scoring system developed for the diagnosis of Acute Appendicitis which showed higher sensitivity, specificity and diagnostic accuracy compared to ALVARADO Score, particularly when applied to Asian population. Not many studies have been conducted to compare RIPASA and ALVARADO scoring systems. Hence, author want to compare prospectively Alvarado and RIPASA score by applying them to the patients attending the hospital with right iliac fossa pain that could probably be acute appendicitis.Methods: A prospective analysis of 116 cases admitted with RIF pain during a 2 years period was performed. Patients between 15-60 years were scored as per Alvarado and RIPASA scoring system. Histopathological reports of the cases were collected and compared with the scores. ROC curve area analysis was performed to examine diagnostic accuracy of RIPASA and ALVARADO scores.Results: The sensitivity of ALVARADO score is estimated to be 52.08 for a cut off of 6. The specificity is 80%, positive predictive value is 92.59, negative predictive value is 25.81. The Diagnostic accuracy of ALVARADO scoring is found to be 56.9. The sensitivity, specificity, positive predictive value and negative predictive values of RIPASA scoring system are 75%, 65%, 91.14%, 35.14%. The diagnostic accuracy of RIPASA score is 73.28.Conclusions: The difference in the diagnostic accuracy between ALVARADO and RIPASA scoring system is significant indicating that the RIPASA score is a much better diagnostic tool for the diagnosis of acute appendicitis. When the ROC curve was observed the area under the curve is high for RIPASA scoring system.

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Usefulness of Grey Scale and Doppler transvaginal sonography in diagnosis of ovarian torsion

Journal of Fatima Jinnah Medical University ◽

10.37018/kori7947 ◽

2020 ◽

Vol 14 (2) ◽

pp. 97-102

Author(s):

Khalid Rehman `Yousaf ◽

Shahzad Saeed ◽

Saman Chaudhry ◽

Rabia Bashrat ◽

Abadullah Khalid ◽

...

Keyword(s):

Positive Predictive Value ◽

Diagnostic Accuracy ◽

Predictive Value ◽

Ovarian Function ◽

Imaging Modality ◽

Ovarian Torsion ◽

Transvaginal Sonography ◽

Predictive Values ◽

Grey Scale ◽

Sensitivity Specificity

Background: Ovarian torsion diagnosis is a great challenge as delay in diagnosis can cause severe morbidity. Early accurate diagnosis is crucial to preserve ovarian function. Ultrasonography being the primary imaging modality plays a vital role in the evaluation of suspected ovarian torsion by helping surgeons reach the correct diagnosis, thus avoiding unnecessary intervention. This study aims to determine the diagnostic accuracy of isolated and combined sonographic features of ovarian torsion on grey scale and Doppler transvaginal ultrasonography. Patients and methods: From radiology database, from January 2016 till December 2019, sonographic signs of ovarian torsion in 113 women with suspected ovarian torsion on ultrasonography and subsequent surgical diagnosis were evaluated. Ultrasound findings were compared with surgical findings to determine the accuracy, sensitivity, specificity, and positive and negative predictive values of individual and combined ultrasound signs. Results: Diagnostic accuracy of ultrasound for ovarian torsion was 85.8%. Abnormal ovarian Doppler flow was the most accurate individual sonographic sign with accuracy, sensitivity, specificity and positive predictive value of 85.8%, 83.5%, 100% and 100% respectively followed by ovarian enlargement and ovarian edema. Combined ultrasound signs resulted in higher sensitivity and positive predictive values, and lower specificity and negative predictive values for ovarian torsion. Increasing the number of sonographic parameters increased the specificity but decreased sensitivity. High accuracy, sensitivity, positive predictive value, specificity and negative predictive value was seen when combination of three or two sonographic parameters was used as diagnostic criteria. Conclusion: Transvaginal sonography is a convenient, reliable and extremely useful imaging modality for preoperative diagnosis of ovarian torsion with high specificity, sensitivity, positive predictive value and diagnostic accuracy helping treating physicians to take prompt decisions regarding timely surgical intervention. However, due to low negative predictive values, absence of sonographic signs does not rule out ovarian torsion and high index of clinical suspicion remains of utmost importance.

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The diagnostic utility of serum IgG4 concentrations in IgG4-related disease

Annals of the Rheumatic Diseases ◽

10.1136/annrheumdis-2013-204907 ◽

2014 ◽

Vol 74 (1) ◽

pp. 14-18 ◽

Cited By ~ 223

Author(s):

Mollie N Carruthers ◽

Arezou Khosroshahi ◽

Tamara Augustin ◽

Vikram Deshpande ◽

John H Stone

Keyword(s):

Positive Predictive Value ◽

Electronic Medical Records ◽

Predictive Value ◽

Medical Records ◽

Elevated Serum ◽

Predictive Values ◽

Test Characteristics ◽

Igg4 Related Disease ◽

Serum Igg4 ◽

Sensitivity Specificity

ObjectivesWe evaluated the sensitivity, specificity and positive and negative predictive values of elevated serum IgG4 concentrations for the diagnosis of IgG4-RD.MethodsBetween 2001 and 2011, 190 unique patients had elevated serum IgG4 measurements. We reviewed electronic medical records to determine the indication for IgG4 measurement and underlying clinical diagnosis. Additionally, we reviewed the records of 190 other randomly selected patients from a pool of 3360 with normal results, to evaluate test characteristics of the IgG4 measurement.ResultsAmong 380 patients analysed, 72 had either probable or definite IgG4-RD. Sixty-five of the 72 IgG4-RD patients had elevated serum IgG4 concentrations (mean: 405 mg/dL; range 140–2000 mg/dL), for a sensitivity of 90%. Among the 308 subjects without IgG4-RD, 125 had elevated IgG4 (mean: 234 mg/dL; range 135–1180 mg/dL) and 183 had normal IgG4 concentrations, for a specificity of 60%. The negative predictive value of a serum IgG4 assay was 96%, but the positive predictive value only 34%. Analysis of the serum IgG4/total IgG ratio did not improve these test characteristics. Doubling the cutoff for IgG4 improved specificity (91%) but decreased sensitivity to 35%.DiscussionMultiple non-IgG4-RD conditions are associated with elevated serum IgG4, leading to poor specificity and low positive predictive value for this test. A substantial subset of patients with biopsy-proven IgG4-RD do not have elevated serum IgG4. Neither doubling the cutoff for serum IgG4 nor examining the serum IgG4/IgG ratio improves the overall test characteristics for the diagnosis of IgG4-RD.

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Validity of the diagnosis of appendicitis in the Danish National Patient Register

Scandinavian Journal of Public Health ◽

10.1177/1403494818761765 ◽

2018 ◽

Vol 48 (1) ◽

pp. 38-42 ◽

Cited By ~ 5

Author(s):

Jakob Kleif ◽

Lau C. Thygesen ◽

Ismail Gögenur

Keyword(s):

Positive Predictive Value ◽

Negative Predictive Value ◽

Predictive Value ◽

Surgical Removal ◽

Predictive Values ◽

National Patient Register ◽

Patient Register ◽

National Patient ◽

Sensitivity Specificity ◽

Danish National Patient Register

Aims: Appendicitis is a common disease. The nationwide Danish National Patient Register provides an important data source for epidemiological research. Data used in register-based epidemiological research needs to be validated. We aimed to validate the diagnosis of appendicitis in the Danish National Patient Register. Methods: From 1997 to 2015 nationwide data from the Danish National Patient Register, the Danish Pathology Register, and the Danish Civil Registration System were used to validate the diagnosis of appendicitis or the combination of the diagnosis for appendicitis and surgical removal of the appendix in the Danish National Patient Register. Sensitivity, specificity, and positive and negative predictive values were calculated using pathology reports as golden standard. Results: Diagnosis of appendicitis in the Danish National Patient Register had a sensitivity, specificity, positive predictive value, and negative predictive value of 0.928 (95% confidence interval (CI): 0.927; 0.930), 0.995 (95% CI: 0.995; 0.995), 0.769 (95% CI: 0.767; 0.771), and 0.999 (95% CI: 0.999; 0.999). A diagnosis of appendicitis and a procedure code for surgical removal of the appendix had a sensitivity, specificity, positive predictive value, and negative predictive value of 0.886 (95% CI: 0.885; 0.888), 0.998 (95% CI: 0.998; 0.998), 0.895 (95% CI: 0.894; 0.897), and 0.998 (95% CI: 0.998; 0.998). Conclusions: The diagnosis of appendicitis alone or in combination with the registered surgical removal of the appendix in the Danish National Patient Register showed acceptable validity. Whether to use the diagnosis for appendicitis only or in combination with procedure codes for the removal of the appendix depends on whether high sensitivity or high positive predictive values are warranted.

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