Development and validation of the Molluscum Contagiosum Diagnostic Tool for Parents: diagnostic accuracy study in primary care

Background

Molluscum contagiosum (MC) is diagnosed by its distinct appearance. Parental diagnosis of MC may reduce anxiety and lead to reductions in healthcare consultations, and may be particularly useful in large-scale epidemiological studies. However, there are currently no published, validated tools allowing parental diagnosis of MC.

Aim

To develop and validate a tool for parental diagnosis of MC.

Design and setting

The Molluscum Contagiosum Diagnostic Tool for Parents (MCDTP) was developed and its diagnostic accuracy was compared with GP diagnosis in 12 GP surgeries in South Wales.

Method

Following development, which involved three phases with dermatologists, nurses, GPs, and parents, parents completed the MCDTP (index test) in the practice waiting room, and rated their confidence in their diagnosis. A GP then examined their child for MC (reference test). Test characteristics were calculated for all responders and for those who expressed being confident or very confident in their diagnosis.

Results

A total of 203 parents completed the MCDTP. The MCDTP showed a sensitivity of 91.5% (95% confidence intervals (CI) = 81.3 to 97.2) and a specificity of 88.2% (95% CI = 81.8 to 93.0) in all parents and a sensitivity of 95.8% (95% CI = 85.7 to 99.5) and a specificity of 90.9% (95% CI = 83.9 to 95.6) in parents who were confident or very confident in their diagnosis. The positive predictive value was 76.1% (95% CI = 64.5 to 85.4) and negative predictive value was 96.2% (95% CI = 91.4 to 98.8) for all parents.

Conclusion

The MCDTP performed well compared with GP diagnosis and is suitable for clinical use by parents and in population-based studies.     

Cell-free Mycobacterium tuberculosis DNA test in pleural effusion for tuberculous pleurisy: a diagnostic accuracy study

ObjectivesTuberculous pleurisy (TP) diagnosis remains difficult, with the sensitivity of Xpert MTB/RIF (Xpert) and mycobacterial culture (culture) only about 30–50%. We aimed to assess the diagnostic performance of a cell-free Mycobacterium tuberculosis DNA test (cf-TB) in pleural effusion for TP.MethodsAdults (≥18 years) with suspected TP presenting with pleural effusion were consecutively recruited, and pleural effusion specimens were prospectively collected in Beijing Chest Hospital, Beijing, China. After centrifuging pleural effusion, sediments were used for culture, Xpert and T-SPOT.TB assay, whereas supernatants were used for cf-TB and adenosine deaminase assay. The diagnostic performance was assessed against a composite reference standard.ResultsFrom June 2015 to December 2018, we prospectively evaluated 286 adults with suspected TP. One hundred twenty-two participants were classified as definite TP based on the prespecified composite reference standard. The cf-TB produced a sensitivity of 79.5% (97/122, 95% confidence interval (CI) 72.4– 86.7) for definite TP, which was superior to Xpert (38.5% (29.9–47.2); 47/122; p < 0.001) and culture (27.1% (19.2–34.9); 33/122; p < 0.001). With pleural effusion Xpert and/or culture as the reference standard, cf-TB showed 96.6% (57/59, 95% CI 92.0–100.0) sensitivity, which was also significantly higher than Xpert (79.7%, 95% CI 69.4–89.9; 47/59; p 0.004) and culture (55.9%, 95% CI: 43.3–68.6; 33/59; p < 0.001).ConclusionsThe cf-TB clearly showed improved sensitivity compared with Xpert and culture. We recommend cf-TB as the first-line test for TP diagnosis.     

Type and accuracy of sphygmomanometers in primary care: a cross-sectional observational study

Background

Previous studies identified worrying levels of sphygmomanometer inaccuracy and have not been repeated in the era of digital measurement of blood pressure

Aim

To establish the type and accuracy of sphygmomanometers in current use

Design and setting

Cross-sectional, observational study in 38 Oxfordshire primary care practices

Method

Sphygmomanometers were evaluated between 50 and 250 mmHg, using Omron PA350 or Scandmed 950831-2 pressure meters.

Results

Six hundred and four sphygmomanometers were identified: 323 digital (53%), 192 aneroid (32%), 79 mercury (13%), and 10 hybrid (2%) devices. Of these, 584 (97%) could be fully tested. Overall, 503/584 (86%) were within 3 mmHg of the reference, 77/584 (13%) had one or more errorof 4-9 mmHg, and 4/584 (<1%) had one or more errorof more than 10 mmHg. Mercury (71/75, 95%) and digital (272/308, 88%) devices were more likely to be within 3 mmHg of the reference standard than aneroid models (150/191, 78%) (Fisher''s exact test P = 0.001). Donated aneroid devices from the pharmaceutical industry performed significantly worse: 10/23 (43%) within 3 mmHg of standard compared to 140/168 (83%) aneroid models from recognised manufacturers (Fisher''s exact test P<0.001). No significant difference was found in performance between manufacturers within each device type, for either aneroid (Fisher''s exact test P = 0.96) or digital (Fisher''s exact test P = 0.7) devices.

Conclusion

Digital sphygmomanometers have largely replaced mercury models in primary care and have equivalent accuracy. Aneroid devices have higherfailure rates than other device types; this appears to be largely accounted forby models from indiscernible manufacturers. Given the availability of inexpensive and accurate digital models, GPs could consider replacing aneroid devices with digital equivalents, especially for home visiting.     

Improving diagnostic accuracy using EHR in emergency departments: A simulation-based study

It is widely believed that Electronic Health Records (EHR) improve medical decision-making by enabling medical staff to access medical information stored in the system. It remains unclear, however, whether EHR indeed fulfills this claim under the severe time constraints of Emergency Departments (EDs). We assessed whether accessing EHR in an ED actually improves decision-making by clinicians. A simulated ED environment was created at the Israel Center for Medical Simulation (MSR). Four different actors were trained to simulate four specific complaints and behavior and ‘consulted’ 26 volunteer ED physicians. Each physician treated half of the cases (randomly) with access to EHR, and their medical decisions were compared to those where the physicians had no access to EHR. Comparison of diagnostic accuracy with and without access showed that accessing the EHR led to an increase in the quality of the clinical decisions. Physicians accessing EHR were more highly informed and thus made more accurate decisions. The percentage of correct diagnoses was higher and these physicians were more confident in their diagnoses and made their decisions faster.     

The validity of diagnostic support of an asthma/COPD service in primary care.

BACKGROUND: To support GPs in diagnosing and monitoring their patients with asthma/chronic obstructive pulmonary disease (COPD), 'asthma/COPD services' have been developed. Within these services, pulmonologists perform structured diagnostic and therapeutic assessments based on the combination of written history data and spirometry. AIM: This study determines the validity of the diagnosis and advice when assessed using only written information. DESIGN OF STUDY: The results of the diagnostic procedures of an asthma/COPD service were compared with the results of regular office consultations by pulmonologists. SETTING: From January until August 2004, two pulmonologists examined 80 randomly selected patients referred to an asthma/COPD service in Eindhoven, the Netherlands. METHOD: Concordance was analysed between diagnosis and advice based on written spirometry and history data, with assessments based on live consultations with the same patients by pulmonologists. RESULTS: The validity of the assessed diagnosis was high (Cohen's kappa = 0.82). When the diagnosis was uncertain, the advice for medical treatment scored low in validity (Cohen's kappa = 0.39). The advice for additional diagnostic examinations had a high internal validity: in half of the patients, uncertainty in diagnosis turned into a definite diagnosis of asthma/COPD, or another cause for the complaints of the patient was revealed; in the other half, the diagnosis of asthma/COPD could be rejected. CONCLUSIONS: A structured asthma/COPD service offering diagnosis and diagnostic advice assessed from written spirometry and history data is a new and valid facility that can support the GP who faces the complicated diagnostic procedures in a progressive number of patients with asthma/COPD.     

Rapid diagnostic test (Leptocheck-WB) for detection of acute leptospirosis: a meta-analysis of diagnostic accuracy

European Journal of Clinical Microbiology & Infectious Diseases - The majority of leptospirosis is subclinical or mild self-limiting systemic illness. A rapid and accurate diagnostic test for...     

A simple diagnostic index for asthma

BACKGROUND: Asthma is becoming increasingly prevalent and a number of research groups are investigating its genetic and environmental basis. OBJECTIVE: To produce a brief screening tool suitable for determining phenotype in asthma research. METHODS: The scores from eight questions on symptoms and history were obtained from 678 adults and 244 children from high asthma-incidence caucasian families. An independent physician diagnosis was also obtained with the use of a modified NHLBI-CSGA questionnaire and pulmonary function test. Stepwise logistic regression was applied to determine which of the eight questions had greatest predictive value for asthma, and the quality of the resultant models was evaluated using an independent set of 643 adults and 239 children. RESULTS: For adults, the most parsimonious model used responses from three of the eight questions. It had sensitivity and specificity of 0.94 and 0.96, respectively. For children, responses to two questions gave a model with sensitivity and specificity of 0.97. For both age groups, negative predictive values were above 0.87. Positive predictive values were 0.58 and 0.78 for adults and children respectively. The latter emphasize the need for conformation, by physician, of "affected" calls made by this initial screen. CONCLUSION: The brief questionnaires described are potentially useful in a research setting, as a preliminary screening mechanism of low cost. Their use will reduce the numbers of subjects that must undergo detailed phenotyping.     

Patient perspectives on test result communication in primary care: a qualitative study

Background

Although the number of blood tests ordered in primary care continues to increase, efficient systems for the communication of blood test results to patients are lacking. This is a concern in terms of both patient safety and patient satisfaction.

Aim

To gain an understanding of patient perspectives on organisational and technological aspects of current and prospective systems for communicating laboratory test results in primary care, and the influences that impact patients’ preferred methods for receiving results.

Design and setting

Qualitative study using patient focus groups in four primary care practices in Birmingham, UK.

Method

The primary care practices were purposively selected to ensure they varied in size, socioeconomic environment, and the default pathways they used to communicate test results. A total of 26 patients from the four practices who had had a recent blood test were recruited. Over a 6 month period in 2011, six, 1-hour focus groups were conducted at the four practices involved in the study.

Results

Patients expressed a preference for receiving results from the ordering GP or a clinically qualified member of staff. Suggestions for refining current systems included improved access to phlebotomy appointments, better management of patient telephone calls, and a clear, accessible protocol for the communication of results.

Conclusion

Despite the testing and result communication process being a core activity in primary care, it was found that practices could improve their service in a number of areas. Patients described frequent delays and inconsistency in both the level of information and the method of communication, as well as dissatisfaction with non-clinical staff relaying results. Patient preferences for result communication based on their experience of current systems have produced practical suggestions to improve processes.     

Diagnostic accuracy of antibody-based rapid diagnostic tests in detecting coronavirus disease 2019: systematic review

IntroductionThe rapid transmission of coronavirus disease 2019 (COVID-19) requires a fast, accurate, and affordable detection method. Despite doubts of their diagnostic accuracy, rapid diagnostic tests (RDTs) are used worldwide due to their practicality. This systematic review aims to determine the diagnostic accuracy of antibody-based RDTs in detecting COVID-19.Material and methodsA literature search was carried out on five journal databases using the PRISMA-P 2015 method. We included all studies published up to February 2021. The risk of bias was evaluated using the Joanna Briggs Institute (JBI) Critical Appraisal Checklist for Diagnostic Test Accuracy Studies. Data regarding peer-review status, study design, test kit information, immunoglobulin class, target antigen, and the number of samples were extracted and tabulated. We estimated the pooled sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) with a 95% confidence interval.ResultsThirty-three studies met the eligibility criteria. The pooled data results showed that the combined detection method of IgM or IgG had the highest sensitivity and NPV, which were 73.41% (95% CI: 72.22–74.57) and 75.34% (95% CI: 74.51–76.16), respectively. The single IgG detection method had the highest specificity and PPV of 96.68% (95% CI: 96.25–97.07) and 95.97% (95% CI: 95.47–96.42%), respectively.ConclusionsAntibody-based RDTs are not satisfactory as primary diagnostic tests but have utility as a screening tool.     

Influenza vaccination in asthma: a primary care experience.

BACKGROUND: Despite the recommendation of the Department of Health that patients with asthma receive annual vaccination against influenza, uptake remains unsatisfactory with many patients suspicious that vaccination is harmful. AIM: To examine the effect of influenza vaccination on asthmatic patients typical of a general practice setting. METHOD: A multicentre study with 56 patients participating from 14 practices in England and Scotland. Patients completed peak expiratory flow rate (PEFR) and symptom diaries for two weeks before and two weeks after influenza vaccination. RESULTS: A non-significant fall in baseline PEFR of 10.5 l/min, from an average of 431.5 l/min, was observed after influenza vaccination, representing a 2% change from baseline. A significant increase in night time reliever use of 0.17 puffs per night (P < 0.01) was found. Non-significant increases in number of nights per week with sleep disturbed due to asthma, severity of night-time and day-time symptoms, and day-time reliever use were also noted. CONCLUSION: Influenza is an important cause of morbidity and mortality in asthmatics. This study confirms the safety of influenza vaccination in patients with asthma typical of those seen in primary care. General practitioners need not hesitate in recommending this valuable intervention to their asthmatic patients and should consider ways in which uptake can be improved.     

Efficacy of a single diagnostic test for sensitization to common inhalant allergens.

BACKGROUND: UniCAP Phadiatop is a single laboratory test designed to determine the presence or absence of specific IgE to a variety of common inhalants. Its purpose is to aid in the differentiation of patients with symptoms attributable to allergic disease from other common causes. METHODS: Consecutive children and adolescent patients (n = 145) at two centers were examined by having their history and physical examination performed by two board certified allergists. Their conclusions along with skin prick tests and specific IgE measurements regarding seven common inhalants (mite, oak, ragweed, grass, dog, cat, Alternaria) were compared with UniCAP Phadiatop test results. This was done using concordance of all test results. Attempts to resolve test discrepancies, when found, included specific RAST inhibitions, total IgE values, and physicians' judgment after testing. RESULTS: All patients with resolved diagnoses (143 of 145, 103 positive and 40 negative) were identified correctly by the UniCAP Phadiatop test. Skin test results and specific IgE measurements correlated well, but neither correlated well with the history by itself, suggesting a minimal false-positive component of the history of 23%. UniCAP Phadiatop results demonstrated a quantitative relationship between the patient's score and the amount of IgE specific to these individual allergens. CONCLUSIONS: The UniCAP Phadiatop test was shown to be highly sensitive and specific in differentiating individuals who are sensitized to common inhalants from those who are not. This test is recommended to all physicians as an aid in diagnostic and referral decisions for patients suspected of having an inhalant allergic diathesis.