Optional extra-credit units

1. Decision or claim I am testing: ____

2. Evidence ID and exact observation: ____

3. Second evidence ID and exact observation: ____

4. Rule that connects the evidence to my claim: ____

5. Strongest alternative or tradeoff: ____

6. Limitation or missing evidence that controls my confidence: ____

7. Revision I would make if the missing evidence changed: ____

Health problem: About 1 in 3 children under age 5 who get a middle-ear infection are diagnosed late because parents cannot tell an ear infection from ordinary fussiness at home.

Why it matters: Late diagnosis raises the risk of temporary hearing loss during peak language-learning years and drives extra clinic visits.

Evidence: Pediatric guidance reports that acute otitis media is one of the most common reasons young children are prescribed antibiotics, and that delayed treatment increases complication rates (cited: class-provided AAP summary, 2013).

Measurable target: cut the average time from first symptom to diagnosis from about 5 days to under 2 days for families using an at-home screener.

Stakeholders affected:

• Parents and caregivers of children under 5
• The children themselves, whose language development is at risk
• Pediatric clinics handling repeat visits

(Tip: a strong problem statement names WHO is affected, gives a NUMBER, and states the specific gap in current care.)

Problem being solved: late at-home detection of childhood ear infections.

Measurable criteria (what success must achieve), ranked:

1. Accuracy: agrees with a clinician's diagnosis at least 90 percent of the time.

2. Speed: gives a result in under 60 seconds.

3. Ease of use: a caregiver can run it correctly with no training.

4. Cost to family: under 5 dollars per use.

Constraints (limits the design must respect):

• Cost: total device build cost under 40 dollars.
• Safety: nothing inserted into the ear canal; no risk of injury.
• Regulations: must fit FDA over-the-counter screening rules, not make a formal diagnosis.
• Time: prototype must be buildable in one 3-week sprint.
• Materials: only classroom-available parts and a phone camera.

Most limiting constraint: the safety rule against inserting anything into the ear canal, because it rules out the easiest sensor placement and forces an external-only design.

(Tip: a criterion is a goal you measure; a constraint is a boundary you cannot cross. Do not mix them in the same list.)

Problem: at-home early screening for childhood ear infection.

Three concepts sketched:

• Concept A: phone-camera otoscope clip that photographs the eardrum for an app to flag redness.
• Concept B: external ear-temperature and pressure sensor that reads infection signs without seeing the eardrum.
• Concept C: symptom-checklist app with a guided caregiver questionnaire, no hardware.

Scoring matrix (1 = weak, 5 = strong), criteria weighted by earlier ranking:

See figure.

Tradeoffs revealed:

• Concept A scores highest on accuracy but lowest on cost and safety (a clip near the ear canal).
• Concept C is cheapest and safest but least accurate because it never looks inside the ear.
• Concept B sits in the middle: safe and external, moderately accurate, moderate cost.

Chosen concept: Concept B, the external sensor. It respects the no-insertion safety constraint, hits a workable cost, and keeps accuracy high enough to trigger a clinic visit. I trade a few accuracy points (versus A) to stay inside the safety constraint that A violates.

(Tip: the winning concept is rarely the top scorer on every row; justify it by the tradeoff you chose to accept.)

Title: External Ear-Infection Screener for At-Home Early Detection

Problem: About 1 in 3 children under 5 are diagnosed late with middle-ear infections because caregivers cannot tell infection from ordinary fussiness at home; target is to cut time-to-diagnosis from about 5 days to under 2.

Criteria and constraints: at least 90 percent agreement with a clinician, result under 60 seconds, under 5 dollars per use, build cost under 40 dollars, no insertion into the ear canal, buildable in one 3-week sprint.

Chosen concept: Concept B, an external ear-temperature and pressure sensor that reads infection signs without entering the ear canal, selected because it respects the no-insertion safety constraint while keeping accuracy high enough to prompt a clinic visit.

Feasibility check: Can it be built within the constraints? Yes for a screening prototype. Off-the-shelf infrared temperature and pressure sensors plus a phone app fit under the 40-dollar build cost and the 3-week sprint. It flags risk; it does not diagnose, which keeps it inside over-the-counter screening rules.

Expected benefit: earlier clinic visits, cutting average time-to-diagnosis toward the under-2-day target and reducing complications from delayed treatment.

One major risk: false reassurance. If the external sensor misses a real infection, a caregiver might delay care. Mitigation: the app always advises a clinic visit for persistent symptoms regardless of the reading.

(Tip: a feasibility check must answer one blunt question in a sentence: can this be built inside the stated constraints? Then name a real risk, not a fake one.)