Students self-assess their knowledge, ability and thinking within many of the active learning modalities. For example, in writing their Muddiest Point, students are actively engaged in metacognition. They are considering which aspects of learning were unclear or confusing and explaining the perceived root of confusion.
An active learning modality that enables course-long self-assessment is called a Knowledge Survey. Our LAMP team has used Knowledge Surveys extensively. In the video below and in the narrative that follows, you will learn how to design and impliment these surveys.
Knowledge surveys are a rich way to monitor your class’s metacognitive growth over the course of a semester. These surveys are generally administered in the first week of the semester and then again in the final week. I took an interest in knowledge surveys about eight years ago when I attended a conference for undergraduate microbiology educators. One of the posters cited Ed Nuhfer’s (2003) work on Knowledge Surveys. The Knowledge Survey reported on in this work was 200-items in length. This length is possible with knowledge surveys that do not ask students to actually answer the question but instead to rate their confidence (self-assessed competence) on a 3-point scale:
A (or 2). I can fully address this item now for graded test purposes.
B (or 1). I have partial knowledge that permits me to address at least 50% of this item.
C (or 0). I am not yet able to address this item adequately for graded test purposes.
When using an in-depth (i.e. 200-item) knowledge survey, one can ask questions that represent every learning outcome for a semester-long class. In fact, this style of knowledge survey is basically a way of converting your learning outcomes into an interactive ‘game’ for students. It allows students to have a complete preview of what they can learn during the semester and how you expect them to show their knowledge. At the end of the semester, taking the knowledge survey again allows them to appreciate how much they have learned / their growth. The questions on the knowledge survey can assess concepts, skills or processes. Questions can be categorized by Bloom Level.
As you begin to consider creating a knowledge survey like this, you are likely thinking about how this will promote your own reflective practice. It requires us, as instructors, to carefully outline all of our outcomes and then convert them to questions that students will be able to interpret well enough to assess their own competence. Indeed, one of the great benefits of a knowledge survey is in promoting your own organization / course preparation (Nuhfer 2003).
When I began implementing knowledge surveys within the microbiology program, one of the first questions that my colleagues asked was, “But does confidence (self-assessed competence) really correlate with knowledge?”. This question spurred a study in which we asked students to both answer the question and indicate their confidence (self-assessed competence) in their answer to this question. This resulted in my first publication on knowledge surveys and was the reason that I met Ed! Now, along with Ed, Kali Nicholas and many other phenomenal colleagues, we have continually shown that most individuals are adequate self-assessors and that collectively people (across demographics) are good at self-assessment! It has been an honor to be a part of this knowledge survey team because together we have called into question the famous “Dunning-Kruger Effect” that labels people as unskilled and unaware. In our most accurate publication in the journal Numeracy, we use paired measures of competence and self-assessed competence to help us better understand privilege. You may also enjoy the article by Ed in Improving with Metacognition. He speaks about using self-assessment to assess higher order thinking.
In our later iterations of knowledge surveys, we used surveys that were much shorter than 200 questions. In some cases, we have tied the knowledge survey concept to concept inventories. The KSSLCI is a 25-question concept inventory that also measures self-assessed competence. We have also found that asking students to answer all questions first and then predict their overall performance is an effective strategy. This is called a global postdicted self-assessment and contrasts with the granular self-assessments in which students assess their competence after answering each item. No matter whether self-assessments are granular or global, we see positive and significant relationships between self-assessed competence and genuine competence (Favazzo, Willford, and Watson 2014; Nuhfer et al. 2016a; 2017; Watson et al. 2019).
The most accurate knowledge survey that I created for my Biological Chemistry course was 35 questions. I decided to administer the knowledge survey in class as this allowed me to indicate to my students how much I valued it. I also decided to only ask for their confidence ratings and not for full answers to the questions. This permitted them to complete the KS during class. Consider working to begin the creation of a knowledge survey for your course. First, determine the style of KS that you would like to employ. The example below will be helpful in this process.
In developing a knowledge survey, your first step is to compile your granular learning outcomes. Below is an example learning outcome for a Microbiology class:
Given a pre-party vodcast and a facilitated model building session students will be able to draw a Gram-positive bacterial cell wall in which the peptidoglycan, teichoic acids and cytoplasmic membrane are accurately depicted and labeled.
Notice that a good learning outcome expresses conditions (what resources the students will be given or generally have). In the above example, the conditions are, “Given a pre-party vodcast and a facilitated model building”. It also has a verb (what the students will be able to do). In this example, the verb is “draw”. Finally, it has standards (to what level will the students be able to do this?). In this example, the standards are in which the peptidoglycan, teichoic acids and cytoplasmic membrane are accurately depicted and labeled.
For the outcome above, a knowledge survey question might state:
I can draw a Gram-positive bacterial cell wall and label the peptidoglycan, teichoic acids and cytoplasmic membrane.
Sample query sound or verb nature
define, list, state, answer who? or what?
List the twenty standard amino acids.
recognize, classify, translate, interpret, paraphrase, explain, predict or provide an example
Use your own words to explain the following passage: Mycorrhizal mutualism enables nitrogen-fixation.
solve, demonstrate, write, draw, calculate or interpret
If a yeast cell, in an aerobic culture completely catabolized 4.5 X 10^9 molecules of glucose, determine the maximum number ATP molecules that could be synthesized via both substrate-level and oxidative phosphorylation.
compare, contrast, differentiate
Compare HIV and SARS-CoV-2 with respect to route of entry , capsid type, genome, route of transmission and exit strategy.
design, construct, develop, build
Design and draw a plasmid that incorporates lac operon and would allow a researcher to visibly determine whether the genes under control of the operon are being expressed.
justify, support, defend
If you were a physician hoping to treat a case of "walking pneumonia" caused by Mycoplasma pneumoniae, which antibiotic would you prescribe? Defend your choice based on bacterial cell wall structure and antibiotic target site.
In this LAMP Coffee & Curriculum Presentation, McKensie Phillips (2019-2020 LAMP Fellow and 2020-2021 LAMP Educator's Learning Community member) describes her research incorporating knowledge surveys more frequently throughout the semester. McKensie's findings indicate that students grow in their self-assessed competence between post-unit and post-semester knowledge surveys!!
In this 2022 LAMP Coffee & Curriculum session, Dr. Ginka Kubelka speaks about her use of knowledge surveys in an Organic Chemistry class. She is joined by Rhiannon Jakopak who uses knowledge surveys to promote self-assessment for students engaging in field experiences.
Favazzo, Lacey, John D. Willford, and Rachel M. Watson. 2014. “Correlating Student Knowledge and Confidence Using a Graded Knowledge Survey to Assess Student Learning in a General Microbiology Classroom.” Journal of Microbiology & Biology Education 15 (2): 251-258. https://dx.doi.org/10.1128/jmbe.v15i2.693. This paper offers an example of using knowledge surveys at the programmatic level.
Dunning, David. 2011. “The Dunning–Kruger Effect: On Being Ignorant of One’s Own Ignorance.” Advances in Experimental Social Psychology 44: 247-296. https://doi.org/10.1016/B978-0-12-385522-0.00005-6. The Dunning Kruger Effect was posited in 1999. The graphs and numerical analyses were shown to be flawed by Nuhfer and others in 2016 and 2017 (see papers below).
Nuhfer, Edward. 2010. Knowledge Surveys. http://elixr.merlot.org/assessment-evaluation/knowledge-surveys/knowledge-surveys2 This links to a learning object site that provides a series of brief video tutorials created by Nuhfer for California State Universities' Merlot site. The project was funded as part of a U.S. DOE grant and provides a good introduction for constructing and interpreting knowledge surveys.
Nuhfer, Ed and Delores Knipp. 2003. The knowledge survey: a tool for all reasons. To Excellerate the Academy 21:59–78. http://pachyderm.cdl.edu/elixr-stories/resource-documents/knowledge-survey/KS_a_too_for_all_reasons.pdf This reference ties employment of knowledge surveys to promotion of student learning. That was the main inspiration to create the instrument. It gives students a way to be mindfully reflective about the content and their own internal mastery of it. It is a way to align affective feelings with cognitive competence. The degree to which affective self-assessments and cognitive test scores correlated and could be used for assessment was not considered relevant .
Nuhfer, Edward, Christopher Cogan, Steven Fleisher, Eric Gaze, and Karl Wirth. 2016 (Nuhfer et al. 2016a). “Random Number Simulations Reveal How Random Noise Affects the Measurements and Graphical Portrayals of Self-Assessed Competency.” Numeracy 9 (1): Article 4: 1-24. http://dx.doi.org/10.5038/1936-46220.127.116.11. First paper peer-reviewed by mathematicians to question the numeracy in use by psychologists for two decades.
Nuhfer, Edward, Steven Fleisher, Christopher Cogan, Karl Wirth, and Eric Gaze. 2017. “How Random Noise and a Graphical Convention Subverted Behavioral Scientists’ Explanations of Self-Assessment Data: Numeracy Underlies Better Alternatives.” Numeracy 10 (1): Article 4: 1-31. http://dx.doi.org/10.5038/1936-4618.104.22.168. Addresses the consequences of two decades of using flawed mathematics to characterize human behavior.
Overbaugh, Richard. C., and Lynn Schultz. n.d. Bloom’s Taxonomy. [Online.] Accessed January 2018 at https://www.odu.edu/content/dam/odu/col-dept/teaching-learning/docs/blooms-taxonomy-handout.pdf
Watson, Rachel M., Edward Nuhfer, Kali Nicholas Moon, Steven Fleisher, Paul Walter, Karl Wirth, Christopher Cogan, Ami Wangeline, and Eric Gaze. "Paired Measures of Competence and Confidence Illuminate Impacts of Privilege on College Students." Numeracy 12, Iss. 2 (2019): Article 2. DOI: https://doi.org/10.5038/1936-4622.214.171.124
What does it take to be a good parent? Literature on parenting identifies four main styles: Authoritative, Authoritarian, Permissive and Uninvolved. These are based on the extent to which parents are responsive (offer warmth and support) and demanding (level of behavioral control). Research has shown that a failure to balance these two key aspects of parenting can have very harmful effects on children and their future conduct. Children who grow up in households where there is too much or too little of one trait (or even worse, no recognizable presence of either), tend to have difficulty with social adjustment and often show poor academic performance. Furthermore, they are at risk of developing low self-esteem and disciplinary problems, which often filter into more serious conditions when they reach adulthood in the form of depression and anxiety.
This test is designed to identify your parenting style, based on the level of responsiveness and demandingness you provide. It is made up of two types of questions: scenarios and self-assessment. For each scenario, answer according to how you would most likely behave in a similar situation. For the self-assessment questions, indicate the degree to which the given statements apply to you. In order to receive the most accurate results, please answer each question as honestly as possible.
After finishing this test you will receive a FREE snapshot report with a summary evaluation and graph. You will then have the option to purchase the full results for $6.95
This test is intended for informational and entertainment purposes only. It is not a substitute for professional diagnosis or for the treatment of any health condition. If you would like to seek the advice of a licensed mental health professional you can search Psychology Today's directory here.
Is your glass half-full or half-empty? On those days when nothing in your life seems to be going right, it can be really tough to see the silver lining among all those clouds. However, it's during these times when the ability to see the good in even the worst situations is so important. An optimistic attitude benefits not only your mental health, but your physical well-being as well. Take this test to see where you fall on the optimism/pessimism continuum.
This test is made up of two types of questions: scenarios and self-assessment. For each scenario, answer according to how you would most likely behave in a similar situation. For the self-assessment questions, indicate the extent to which you agree with the given statements. In order to receive the most accurate results, please answer each question as honestly as possible.
After finishing this test you will receive a FREE snapshot report with a summary evaluation and graph. You will then have the option to purchase the full results for $4.95
This test is intended for informational and entertainment purposes only. It is not a substitute for professional diagnosis or for the treatment of any health condition. If you would like to seek the advice of a licensed mental health professional you can search Psychology Today's directory here.
Sam Ashe-Edmunds has been writing and lecturing for decades. He has worked in the corporate and nonprofit arenas as a C-Suite executive, serving on several nonprofit boards. He is an internationally traveled sport science writer and lecturer. He has been published in print publications such as Entrepreneur, Tennis, SI for Kids, Chicago Tribune, Sacramento Bee, and on websites such Smart-Healthy-Living.net, SmartyCents and Youthletic. Edmunds has a bachelor's degree in journalism.
HIV testing is usually provided by medical professionals in hospital clinics, GP surgeries and other settings. It may also be provided by trained staff from HIV and community health organisations. In addition, there are two different ways you can get tested for HIV at home:
You don’t need to see a doctor or nurse, and you can use these kits wherever you want, including at home. For that reason, both approaches are often referred to as ‘home testing’. For clarity, this factsheet uses the terms ‘self-sampling’ and ‘self-testing’.
In the UK, many sexual health clinics offer free self-sampling services, and they may also be available online through websites like freetesting.hiv. Commercial companies including Lloyds Pharmacy and Superdrug also offer self-sampling kits. Self-sampling has always been legal in the United Kingdom.
There are some differences but generally the services work as follows:
You might be able to send samples to test for sexually transmitted infections like chlamydia and gonorrhoea at the same time. For example, you’d need to take a swab from the urethra, vagina, cervix, throat and/or rectum. A blood sample can also be tested for syphilis. One advantage of self-sampling over self-testing is that you can be tested for more infections at the same time. There aren’t any self-tests for chlamydia or gonorrhoea.
Self-testing is different from self-sampling in that you perform the whole test yourself and you get the result immediately.
It used to be illegal to sell or advertise HIV self-testing kits in the UK – HIV testing equipment could only be sold to medical professionals. These restrictions were lifted in April 2014. Testing kits designed to be used by members of the public can be sold as long as the kit carries a CE mark to show it meets European performance and safety requirements.
At present, three CE marked tests are available. The first two involves using a safety lancet to produce a drop of blood from a finger and applying the blood to the test device. The tests’ names are the INSTI HIV Self Test and the Simplitude ByMe HIV Self Test. The result can be read instantly (INSTI) or after 15 minutes (Simplitude ByMe). Studies suggest that the tests are very accurate, except for cases of accurate infection.
The third test is the OraQuick In-Home HIV Test. This needs a sample of moisture from the mouth and gives results in 20 minutes. It isn’t quite as reliable as the tests used by medical professionals – in a study it gave an accurate result to 93% of people who had HIV and 99.9% of people who did not have HIV.
The tests are sold for around £30 through the manufacturers’ websites: INSTI, Simplitude ByMe and OraQuick, as well as from online pharmacies.
In addition, unregulated self-testing kits continue to be available from internet retailers. These kits may not meet European standards and may provide inaccurate results. They may have been designed for use by medical professionals and be difficult for others to use correctly.
The HIV tests licensed for use in the UK are extremely accurate. Nonetheless, no medical test is perfect. For this reason, medical professionals never tell someone they have HIV on the basis of one test result – if the result suggests infection with HIV, it must be confirmed with two more tests, using a different type of test kit each time.
The same rules apply with self-sampling and self-testing.
If a test shows you might have HIV then you’ll need to take more tests to confirm the result. These extra tests are best done at a sexual health clinic, where they have access to the most accurate HIV testing technologies.
Clinic staff can also provide you support and medical care.
If there are no signs of HIV (‘HIV negative’), you need to take into account the test’s ‘window period’. In general, tests are not able to detect HIV until a few weeks after it was caught. The window period varies; some of the difference depends on the type of sample.
Some self-sampling services ask you to collect a tiny tube of blood, which you send off to a laboratory. In this case, the window period is the same as for many HIV tests used by health professionals. The test is usually able to detect HIV that was caught four weeks (one month) ago. But occasionally it can take up to 12 weeks (three months).
The INSTI HIV Self Test has a similar window period. It will usually be able to detect HIV that was caught four weeks (one month) ago. But occasionally it can take up to 12 weeks (three months). The manufacturer of the Simplitude ByMe HIV Self Test say that their window period is 12 weeks (three months).
If the sample is moisture from your mouth, the window period may be longer. It may also be a little longer if the sample is a drop of blood squeezed onto a piece of paper. In these cases, tests are frequently able to detect HIV that was caught between four and eight weeks ago. But it may take up to 12 weeks for infections to be detected. This applies both to self-sampling using these kinds of samples and the OraQuick self-test.
The information on window periods means that if you test less than 12 weeks after an activity which could have exposed you to HIV (like sex without a condom), then an HIV-negative result is not definitive. You can only be sure by testing 12 weeks after the last risky activity.
One specific situation in which self-tests are not reliable is when you are taking antiretroviral medications, either as HIV treatment, pre-exposure prophylaxis (PrEP) or post-exposure prophylaxis (PEP). For example, sometimes people have a doubt about their HIV diagnosis and use a self-test to check or reconfirm their HIV status. The results are sometimes inaccurate in these situations.
The vast majority of people are likely to receive accurate results when using self-sampling and self-testing. They are also convenient ways to test. However, if you have any concerns, you may prefer to test at a clinic, where they use the most advanced HIV testing technologies.
Many people prefer home testing because it’s quick, doesn’t require a trip to a clinic and may feel more private. The convenience of these services could help you to test regularly. Home-testing kits have been designed to be easy to use. Nonetheless, you need to follow the instructions carefully to get an accurate result.
Some people prefer to go to a clinic where they are tested by a medical professional and can also be tested for other sexually transmitted infections. Also, if the test result is unclear or might be positive, staff can provide you advice and check the result with additional tests straightaway.
Before testing by yourself, it’s worth thinking about how you would cope if the test showed you might have HIV. It may be up to you to seek advice and support. This will be available from the service providing the test, local HIV organisations, sexual health clinics and HIV clinics. It would be very important to go to a clinic to have the test result checked.
HIV testing offered by NHS clinics and charities is free of charge. However, a service offered by a private company may cost around £40.
The COVID-19 pandemic is like a roller coaster. One minute we see the light at the end of the tunnel and the next thing we know, more cases are on the rise.
The good news? It’s not 2020 anymore. Instead of waiting on testing center lines for hours on end, people have turned primarily to at-home COVID tests that they can use in the comfort of their own homes.
According to the CDC, COVID-19 self-tests — also known as at-home tests or over-the-counter (OTC) tests — are one of many risk-reduction measures, along with vaccination, masking and physical distancing, that protects you and others from the spread of COVID-19, even though it’s no longer mandated in most regions.
While at-home covid tests were nearly impossible to find online or in stores at many points in time over the last few years, many brands have replenished their stock. Ahead, get all the info on how to use at-home COVID-19 tests, how accurate they are and where you can buy them online.
Of course, read the complete manufacturer’s instructions for use before starting the test and make sure you talk to a healthcare provider if you have questions about the test or your results. Here are general steps to take a self-test, according to the CDC.
Invalid test results are rare but can occur. Chief Infection Control Officer Roy Chemaly, M.D. at the University of Texas MD Cancer Center said that “the tests are only accurate 80% of the time, and sometimes less.”
Sometimes invalid results or an error can show on the test device. Invalid results or an error can occur for many reasons — your specimen may not have been collected correctly, or the test may have malfunctioned.
Due to the current infection rate of the coronavirus being so high, many professionals suggest retesting with a PCR test if you have symptoms and test negative using an at-home antigen test as it could be a false negative.
Get your test results in 15 minutes or less with a simple nasal swab in the comfort and convenience of your home. BinaxNOW COVID-19 Antigen Self Test is available under FDA Emergency Use Authorization.
This simple at-home test is authorized for non-prescriptive home use with self-collected direct anterior nasal (NS) swab specimens from individuals aged 14 and older, and with adult-collected anterior NS samples from those 2 years or older.
It’s most effective within six days of symptoms or 24 to 48 hours after suspected exposure.
The FlowFlex Covid-19 Antigen Home Test is selling for as low as $6, an accurate, easy to use and quick-result option to buy online.
This FDA-authorized Antigen test requires only one test to get results in 15 minutes using a nasal swab.
If you work best with technology, On/Go is the COVID-19 self-test for you. This kit gives you 95% accurate results in just 10 minutes using the companion mobile app, which guides you through each step of the process — from sample collection to results.
This product comes with two rapid antigen tests that are simple to use.
Prepare the testing materials, collect and process the sample, then receive your results in just 15 minutes.
This test requires less than one minute of hands-on time. InteliSwab has received FDA Emergency Use Authorization for self-testing. You do not need to ship samples to a lab or get a prescription from your healthcare provider. Get your result in 30 minutes.
The Ellume COVID-19 test requires you to obtain the Ellume COVID Test App to your smartphone. Next, answer a few questions and watch the informational video. After that, you’ll be all set to perform the easy-to-use test and receive results in 15 minutes.
Celltrion DiaTrust COVID-19 Ag Home Test is an FDA EUA-authorized COVID-19 rapid antigen at-home testing kit. Self-test in the comfort of your own home, and get the relief you need in just 15 minutes.
Each kit contains supplies for two tests: swabs, test devices, test tubes (extraction buffer), filter caps, and an Instructions for Use manual. Test tubes and filter caps for two tests are enclosed in one inner package.
If you want a test that’s even more reliable but you don’t want to leave the comfort of your home, an at-home PCR test is the way to go. The Pixel by LabCorp kit is a great option that gets you results within 1-2 business days (on average) after receiving your nasal swap sample via FedEx.
The BOSON Rapid SARS-CoV-2 Antigen Test (2-Test Pack) is an easy-to-use at-home test where you’ll receive results in 15 minutes. Each kit contains two tests and is recommended for ages 14 and up. More, you’ll enjoy its convenience and ability to skip the lab.
Check out the New York Post Shopping section for more content.
If the COVID-19 pandemic taught us anything, it’s the value of testing for infection at home without the need to visit a health facility. Now a series of studies have found that testing for sexually transmitted infections (STIs) in the privacy of your own home has the potential to Excellerate treatment by removing the stigma associated with maintaining sexual health.
The other thing that occurred over the years following the arrival of the COVID pandemic was an increase in STIs. According to the Centers for Disease Control and Prevention, between 2020 and 2021 reported US cases of chlamydia and gonorrhea increased by 4% and syphilis by 32%, making detection and treatment of these curable diseases a priority.
Self-testing already exists for HIV and the hepatitis C virus, prompting researchers, led by Monash University, to undertake a world-first global systematic review of studies of syphilis self-testing (SST) to evaluate its value.
“The COVID-19 pandemic has shown us the value of self-tests,” said Jason Ong, corresponding author of the study. “Syphilis self-testing is a key that unlocks the door to widespread testing and treatment, much like self-testing has done for HIV, hepatitis C and COVID-19.”
Transmitted during oral, vaginal and anal sex, in pregnancy and through blood transfusion, syphilis is a preventable, curable bacterial STI that can lead to serious health issues if untreated.
The researchers considered 11 publications from seven studies between 2000 and 2022 that included data on any syphilis rapid tests or dual HIV-syphilis tests. SST was defined as any test performed by someone who collects a specimen, performs the test, and interprets the results themselves.
Analyzing the data, the researchers considered test accuracy, usability, the proportion of participants who performed the test (uptake), the number of participants who tested positive for syphilis, linkage to sexual health services or confirmatory testing after testing positive, cost, and any harm that followed testing, such as self-harm, pressure to test or disclose results.
They found a relatively high uptake and acceptability of SST and a lower cost per person compared with facility-based testing. Participants reported convenience, privacy, rapid results, autonomy, empowerment, decreased contact with facilities and money or time savings as reasons for using SST. However, some important challenges were noted, including a lack of knowledge of SST and STIs, and privacy concerns when using apps or social media to report results.
Overall, though, the researchers found compelling evidence that SST was safe, acceptable, effective to implement, and cost-effective, particularly among individuals that would ordinarily fall outside of existing health services. They concluded that the potential benefits of SST outweighed any potential risks.
“If we can Excellerate access to self-testing for syphilis, we can also have a major impact on the current syphilis epidemic in Australia and beyond,” said Ong. “This has global policy implications for countries to license and allow syphilis self-testing kits to be accessible, so that populations who are less likely to attend facilities to test are able to test themselves privately, accurately and at their convenience.”
Meanwhile, two studies presented at the 2023 Annual Scientific Meeting and Clinical Lab Expo in Anaheim assessed the reliability of self-tests to detect common STIs, human papillomavirus (HPV), chlamydia and gonorrhea. The Expo is put on by the Association for Diagnostic and Laboratory Medicine, formerly the American Association for Clinical Chemistry (AACC).
HPV is the leading cause of cervical cancer, a common virus that’s passed from one person to another during sex. Currently, HPV is detected by way of a cervical swab taken in a clinical setting.
In one study, researchers from LetsGetChecked Laboratories and the Permanente Medical Group compared the performance of 144 pairs of self-collected and provider-collected cervical swabs to test for HPV. Some of the self-collected specimens were exposed to temperatures that simulated extreme weather fluctuations. They found that most self-collected samples provided the same results as provider-collected ones. Discrepancies were due to smaller amounts of detectable virus on the samples, caused by exposure to extreme temperatures. sample validity improved by 8.5% when participants were shown an instruction video.
In another study, researchers from the Los Angeles County Department of Public Health and LetsGetChecked Laboratories compared provider-collected and self-collected tests for the bacteria Chlamydia trachomatis and Neisseria gonorrhoeae, which cause chlamydia and gonorrhea.
Chlamydia is a very common STI that, if left untreated, can cause pelvic inflammatory disease in women and lead to chronic pain and infertility. In men, untreated chlamydia can cause testicular pain and swelling. Gonorrhea can cause infection in the genitals, rectum, and throat. It can lead to infertility in women if left untreated. Both STIs often present without symptoms.
The researchers compared results from 164 pairs of provider-collected and home-collected rectal swabs and 159 pairs of throat swabs. They also assessed urine and vaginal swabs for the impact of temperature fluctuations, hand contaminants, and under- or overfilling of self-collected urine samples.
Compared to provider-collected samples, the self-collected rectal swabs showed 95.5% agreement for detecting the bacteria that caused chlamydia and 100% for the gonorrhea bacteria. Self-collected throat swabs agreed with provider-collected swabs for both infections almost 100% of the time. Interestingly, several self-collected swabs picked up both bacteria, whereas the provider-collected ones didn’t. Hand contaminants were found to have little impact on test performance, and results were largely unaffected by temperature changes and improper filling of urine samples.
“Self-collected rectal and throat swabs could offer better sensitivity than those collected by physicians for detecting C. trachomatis and N. gonorrhoeae – without comprising the test’s analytical performance,” said Brendan Hockman, one of the study’s authors. “Therefore, specimens of STIs collected at home offer a viable option for improving access to STI screening and could offer a non-stigmatizing approach to sexual health.”
Each of these studies suggests that self-testing for STIs is not only accurate and cost-effective but could also reduce the global impact of these diseases in a way that is private and removes stigma.
The Monash University study was published in the journal The Lancet Public Health.
Source: Monash University, Association for Diagnostics & Laboratory Medicine via Newswise
NT Self-assessment articles offer bite-size continuing professional development (CPD). Each article comes with a multiple-choice assessment with feedback. If you score 80% or more in the assessment, you can obtain a personalised certificate to use as evidence of your CPD for appraisals and to count towards revalidation.
Test yourself on this month’s article or choose from our Self-assessment archive below.
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HIV self-testing involves collecting your own specimen (oral fluid or blood) and using a rapid HIV test kit. You perform the whole test yourself, including studying and interpreting the test result.
This is different from HIV self-sampling. With self-sampling, you collect your own sample and send it to a laboratory for analysis. We have another page on the accuracy of self-sampling.
Self-testing is sometimes called ‘home testing’, because people often do it at home. The World Health Organization (WHO) recommends that HIV self-testing should be offered alongside existing HIV testing services.
Self-tests are usually modified versions of rapid, point-of-care test kits that were originally designed for healthcare professionals. Their processes, packaging and instructions have been simplified so as to guide you through the steps of taking a test.
With some tests, you use a lancet to release a small quantity of blood from a fingerprick. Other tests require a sample of oral fluid, obtained by swabbing an absorbent pad around the outer gums, adjacent to the teeth.
Self-tests may be second- or third-generation HIV tests. They are only able to detect HIV antibodies, whereas the fourth-generation HIV tests which are normally used by healthcare professionals are also able to detect p24 antigen (a protein contained in HIV's viral core that can be detected in the first few weeks after infection). Fourth-generation tests are therefore better at picking up accurate infections.
Second- and third-generation tests can accurately detect chronic (long standing) HIV infection. But their ability to detect recently acquired HIV is more variable.
Their window periods are a little longer than for other tests. The window period is the time immediately after infection when tests may not detect markers of infection and therefore provide a false negative result.
Across the world, the majority of HIV self-tests are based on second-generation testing technology. They can detect immunoglobulin G (IgG) antibodies, but not immunoglobulin M (IgM) antibodies or p24 viral antigen. As these two substances are detectable sooner after HIV infection than IgG antibodies, second-generation tests have longer window periods. The OraQuick In-Home HIV Test, SURE CHECK HIV Self Test and autotest VIH are CE-marked second-generation self-tests.
The SURE CHECK HIV Self Test and autotest VIH are both adapted from a device that is widely used by health professionals. This may be marketed either as the Chembio Sure Check HIV 1/2 Assay or as the Clearview Complete HIV 1/2 Assay. In relation to use by health professionals, American regulators assessed this assay’s sensitivity (proportion of HIV-positive samples accurately described as such) to be 99.7% and its specificity (proportion of HIV-negative samples accurately described as such) to be 99.9%. In relation to the two self-tests, studies to assess the ability of lay users to follow instructions, use the test and correctly interpret its results found that 97-98% achieved a valid result.
Other HIV self-tests are based on third-generation testing technology. They can detect immunoglobulin G (IgG) antibodies and immunoglobulin M (IgM) antibodies, therefore shortening the window period. The INSTI HIV Self Test, Exacto Test HIV and atomo HIV Self Test are CE-marked third-generation tests. In some countries, the atomo device is repackaged and marketed as the Mylan HIV Self Test or as the Simplitude ByMe HIV Self Test.
The INSTI HIV Self Test is adapted from the INSTI HIV-1/HIV-2 Antibody Test for personal use. This is one of the most accurate third-generation tests available, with a superior sensitivity to accurate infection. When used by health professionals, the test’s sensitivity and specificity were both calculated to be 99.8%.
A review identified 25 studies in which people used self-tests, with their results compared with those of a healthcare worker testing them at the same time. The original studies were done in a mix of North American, African, European and Asian countries. Fifteen studies used oral fluid-based tests, six used blood-based tests and four used both oral and blood specimens. Of note, several studies were evaluating professional assays that had not been adapted for use as self-tests – performance could be better in commercially marketed tests.
The researchers found that most people could reliably and accurately use rapid tests. Using a statistical approach known as Cohen’s kappa in which 1 represents perfect agreement between the results of a self-tester and a trained health worker and less than 1 represents less than perfect agreement, results were highly concordant. The Cohen’s kappa was 0.98 in studies in which users first received a demonstration of how to do the self-test or to interpret its result. In studies in which this was not provided, it was 0.97. This means that in only a small minority of cases the self-tester and the healthcare worker got results that were different from each other.
There were more invalid results in people using blood-based tests (0.4-9.5%) than studies using oral fluid-based tests (0.2-4.5%). Common errors included incorrect or incomplete specimen collection, spilling or incorrect use of the buffer solution, problems transferring blood samples, and difficulties with the interpretation of results.
Although blood-based rapid diagnostic tests might have the potential to deliver more accurate results, more invalid results might occur because the greatest number of user errors was related to standard procedures when capillary tubes and pipettes were used. Simpler test procedures and clearer instructions might mitigate these problems.
Performance of self-tests is poorer in a number of situations. Results may not be accurate.
There are three possible test results:
1) Negative (may also be described as ‘non-reactive’). The test did not find any evidence of HIV infection. You probably don’t have HIV (so long as you aren’t testing in one of the situations described in the last section).
2) Reactive (often incorrectly described as ‘positive’ by manufacturers). The test assay has reacted to a substance in your blood. This does not necessarily mean that you are HIV positive. It means you need to take more tests to confirm the result. These extra tests are best done at a healthcare facility where they have access to the most accurate HIV testing technologies.
3) ‘Indeterminate’, ‘equivocal’ or ‘invalid’. The test result is unclear. Another test needs to be done.