Specificity vs sensitivity
Distinguish specificity from sensitivity and use your ELISA results to discuss how good the test is.
2x2 classification table sorting ELISA results into true/false positives and negatives, plus a one-sentence reliability judgment citing controls.
- 1Do thisDistinguish specificity from sensitivity and use your ELISA results to discuss how good the test is.
- 2Use this resource
- 3Submit thisData table: 2x2 classification table sorting ELISA results into true/false positives and negatives, plus a one-sentence reliability judgment citing controls.
- 4Submit it here
- 1CMSD website. Go to clevelandmetroschools.org and click the Clever button.
- 2Clever. Clever opens. Sign in if it asks.
- 3Microsoft (district) login. Use your district Microsoft account (the one for school).
- 4Schoology. Open Schoology, then your class, then Assignments, and find the file named below.
The file to submit is named: Genetics of Disease (Medical Interventions) › Reading qualitative vs. quantitative color results; false positive/negative risk; control logic. › Data tableOpen Schoology
- CER:
- Claim, Evidence, Reasoning — make a claim, back it with evidence, explain your reasoning.
- SOP:
- Standard Operating Procedure — the exact steps to follow (especially in a lab).
- Tracker:
- Your PLTW progress log where you record completed evidence.
- myPLTW:
- The PLTW course site where you do the online activities — you open it through Schoology.
Minute-by-minute · 80-minute block
💡 Big idea: How do scientists measure the reliability of a diagnostic test, and why does the right balance depend on the disease?
- 0-10 minWrite plain definitions of sensitivity and specificity; draw the 2x2 table (true positive, true negative, false positive, false negative)
- 10-25 minSort Wednesday's ELISA results into the four categories using your plate photo and data table
- 25-40 minClassify any anomalous results: sensitivity problem (missed a true positive) or specificity problem (flagged a true negative)?
- 40-55 minExplain in writing why a screening test favors sensitivity; connect to Monday's false-results bioethics discussion
- 55-68 minConnect your controls to the test's specificity: did the negative control stay negative? Explain what it proves
- 68-80 minWrite one trustworthiness judgment sentence; share with a partner and defend your reasoning
- • A test that is 99% accurate sounds great; but if the disease is rare, most positive results could still be false positives.
- • Sensitivity and specificity are the two numbers that determine whether a test is useful for a given situation.
- • Today you apply both concepts directly to your own ELISA data from Wednesday.
- • Exit goal: a completed 2x2 classification table and a trustworthiness judgment sentence.
- 1Write plain definitions: sensitivity catches true positives, specificity avoids false positives.
- 2Sort your ELISA results into true positives, true negatives, and any apparent errors.
- 3Decide whether any odd result looks like a sensitivity or a specificity problem.
- 4Explain why a screening test often favors sensitivity over specificity.
- 5Connect your controls to how you would trust the test's specificity.
- 6Write one sentence judging how trustworthy your ELISA run was and why.
- • You will be able to define sensitivity and specificity.
- • You will be able to classify results as true or false positives and negatives.
- • You will be able to judge a test's reliability from its results.
- • Sensitivity measures how well a test catches true positives (sick people who test positive); a sensitive test misses few sick people.
- • Specificity measures how well a test avoids false positives (healthy people who test positive); a specific test rarely flags healthy people as sick.
- • Screening tests (population-level) favor high sensitivity; confirmatory tests favor high specificity.
Your PLTW work today
Reading qualitative vs. quantitative color results; false positive/negative risk; control logic. · Specificity vs sensitivity
Day 4 of this lesson. Open this exact section in myPLTW (reached through Schoology), then do the work below.
Do this: Open the standard-curve analysis section of Activity 1.1.5 ELISA in myPLTW and plot your results.
Complete the standard curve, mark your unknown sample on it, and calculate its estimated concentration.
Well-color data should be recorded (Wednesday); standard curve plotted and concentration estimated today.
Standard-curve graph with unknown marked and concentration calculated in notebook.
All PLTW activities are completed inside the PLTW course environment — this page only gives direction. Submit producibles on Schoology.
Today's PLTW tracker
Check things off as you work, then submit. This tells Mr. Mendoza how you're doing so he can help the class. It does not replace turning in your producible on Schoology.
Use the code Mr. Mendoza gave you, not your name. Saved on this device.
Reading qualitative vs. quantitative color results; false positive/negative risk; control logic. · Specificity vs sensitivity
Open the standard-curve analysis section of Activity 1.1.5 ELISA in myPLTW and plot your results.
Well-color data should be recorded (Wednesday); standard curve plotted and concentration estimated today.
This is how Mr. Mendoza sees the class keeping pace with PLTW. Be honest, it only helps if it is accurate.
🎯 Distinguish specificity from sensitivity and use your ELISA results to discuss how good the test is.
- Write plain definitions: sensitivity catches true positives, specificity avoids false positives.
- Sort your ELISA results into true positives, true negatives, and any apparent errors.
- Decide whether any odd result looks like a sensitivity or a specificity problem.
- Explain why a screening test often favors sensitivity over specificity.
- Connect your controls to how you would trust the test's specificity.
- Write one sentence judging how trustworthy your ELISA run was and why.
Data table: 2x2 classification table sorting ELISA results into true/false positives and negatives, plus a one-sentence reliability judgment citing controls.
Submit on SchoologyUpload by 11:29 PM for full credit.
| Task | Who |
|---|---|
| Write plain definitions: sensitivity catches true positives, specificity avoids false positives. | _______ |
| Sort your ELISA results into true positives, true negatives, and any apparent errors. | _______ |
| Decide whether any odd result looks like a sensitivity or a specificity problem. | _______ |
| Explain why a screening test often favors sensitivity over specificity. | _______ |
| Connect your controls to how you would trust the test's specificity. | _______ |
| Write one sentence judging how trustworthy your ELISA run was and why. | _______ |
Working solo? Put your own name in "Who" for every row.
- You will be able to define sensitivity and specificity.
- You will be able to classify results as true or false positives and negatives.
- You will be able to judge a test's reliability from its results.
Teacher-posted resources
Classroom documents for this lesson. Ones marked “Open the file” open right here; the rest are posted in Schoology. Use the label on each card to choose the right move.
Open this when the class reaches this activity and use it to complete the required lesson artifact.
Placement rationale
Matched ELISA lab, controls, diagnosis limits by path:Medical-Interventions/Unit-1_How-to-Fight-Infection/1.1_The-Mystery-Infection; keywords:elisa, lab. Score 138. Visibility: student-schoology (student-facing resource; link through Schoology rather than local path).
Use this if you were absent, got stuck, or need another pass before you submit the lesson artifact.
Placement rationale
Matched ELISA lab, controls, diagnosis limits by path:Medical-Interventions/Unit-1_How-to-Fight-Infection/1.1_The-Mystery-Infection; keywords:elisa, lab. Score 138. Visibility: student-schoology (student-facing resource; link through Schoology rather than local path).
Open this when the class reaches this activity and use it to complete the required lesson artifact.
Placement rationale
Matched ELISA lab, controls, diagnosis limits by path:Medical-Interventions/Unit-1_How-to-Fight-Infection/1.1_The-Mystery-Infection; keywords:elisa, lab. Score 138. Visibility: student-schoology (student-facing resource; link through Schoology rather than local path).
How to get there: open the CMSD website, click Clever, sign in with your Microsoft (district) account, then open Schoology from Clever.
Lab & supplies
WebXam practice
Cumulative WebXam review
A quick mixed-review pulling questions from earlier units plus today, so the WebXam material stays fresh.
Where this leads — careers
What today's skills lead to. These are real health-science careers this course builds toward. Tap one to see, on the US Department of Labor's O*NET site, what the job actually involves, what it pays, and how fast it is growing.
What to do if you were absent
Today is individual PLTW work, so do exactly what we did in class, from home: complete the same PLTW target above, then submit your Data table.
Open Schoology (CMSD) and keep goingHow to get there: open the CMSD website, click Clever, sign in with your Microsoft (district) account, then open Schoology from Clever.
Class still runs. Complete the online activity above (it's self-guided). Need the concept taught without a teacher? Use this authoritative explainer:
HHMI BioInteractive- CompleteEvery required part of the artifact is present, nothing left blank.
- AccurateThe science and the data are correct and match the evidence.
- Scientific reasoningYou explain your claim with evidence and reasoning (CER), not just an answer.
- Professional communicationClear, organized, labeled, and written the way a clinician or scientist would.
- SubmittedTurned in the right way (Schoology for routine work) and confirmed.
Drop your Wed, Sep 23, 2026 · Specificity vs sensitivity here. Use a clear file name (your initials + project). Routine work still goes to Schoology (via the CMSD portal).
Upload a project