Otoacoustic Emissions
Design, run, and score distortion-product OAE (DPOAE) testing — read the DP-gram, judge SNR and noise floor, and issue a pass/refer per ear.
The Otoacoustic Emissions element simulates distortion-product OAE (DPOAE) testing. For each ear it presents a set of test frequencies; at each one the learner acquires the measured DP amplitude and noise floor, reads the DP-gram, judges the signal-to-noise ratio (SNR) and whether the noise floor is acceptable, classifies the emission, and issues an overall pass / refer decision. In the designer it's listed as:
Distortion product OAEs — read the DP-gram, judge SNR / noise floor, and pass/refer
Like every Theta element, it follows the lifecycle Design → Settings → Testing → Scoring → Report.
Every call is a two-way call
Emission is Present or Absent. Noise floor is OK or High. The ear Passes or Refers. There is no third "inconclusive" option anywhere in the element — a high noise floor doesn't create a separate verdict, it means that frequency can't count toward a pass.
Design
The Design tab is where you set the true emission picture the learner must discover, per ear and per frequency.
Protocol and frequencies
Two starting protocols are offered:
| Protocol | Frequencies (Hz) |
|---|---|
| Screening | 2000, 3000, 4000, 5000 |
| Diagnostic | 500, 1000, 2000, 3000, 4000, 6000, 8000 |
You can add or remove any f₂ frequency from the master list (500 – 8000 Hz); at least one is required.
Per-frequency values: template vs fixed
As with the other clinical elements, template vs fixed is chosen on the element card.
| Mode | What you set per frequency |
|---|---|
| Fixed values | The exact DP amplitude and noise floor (dB SPL) used on every submission. |
| Template | Two categories per frequency: an emission category (Present or Absent) and a noise-floor category (Acceptable or Elevated). Each submission draws realistic dB values inside those categories, so numbers vary but the present/absent picture stays stable. |
Present generates a DP that clears the SNR criterion and amplitude floor; Absent generates a DP sitting in the noise.
In fixed mode the dB numbers are the design — editing a DP or NF value re-derives that row's emission and noise-floor category under the current criteria. The category you see always matches the numbers the learner will see, so the answer key can't drift away from the case.
Quick-fill patterns
To seed both ears fast (then edit individual cells), pick a pattern — All present (normal), All absent (refer), Partial (high-frequency loss) (frequencies ≥ 3 kHz absent), or Noisy recording (elevated noise floor) — and apply it to the Right ear, Left ear, or bilaterally.
A quick-fill only rebuilds ears that exist: an ear you removed with Remove ear stays untested. "Affected ear" chooses which ear is abnormal, not which ears are present.
Scored frequencies
Per ear, a checkbox on each frequency chooses whether it counts toward scoring (default: all tested frequencies). An unticked frequency is still presented to the learner and still appears on the report — it just isn't marked.
Unticking every frequency is allowed and means exactly what it says: no per-frequency marks for that ear. A note in the designer confirms it, so it can't happen silently. The ear's overall Pass/Refer is a separate field with its own Scored / Report-only / Off control on the Scoring tab, and is unaffected by this list — as is the pass rule itself, which always reads every tested frequency.
Scoring scope isn't the clinical rule
Unticking a frequency changes what earns points. It does not change the pass/refer answer — that rule always counts every tested frequency, so the learner can always derive it from what's in front of them.
Settings
The Settings tab holds the element-wide validity rules and display values. The interpretation rules update live as you change them.
| Setting | Default | What it does |
|---|---|---|
| SNR criterion | 6 dB | A frequency is present if SNR ≥ this and DP ≥ the amplitude floor. |
| DP amplitude floor | −5 dB SPL | Absolute DP level a present emission must clear. |
| Max acceptable noise floor | 10 dB SPL | Above this the noise floor is high — that frequency can't count toward a pass. |
| Min frequencies to pass | 3 | Overall pass needs at least this many tested frequencies present with an acceptable floor. |
| L1 / L2 | 65 / 55 dB SPL | Primary tone levels, shown for context. |
| f2/f1 ratio | 1.22 | Primary frequency ratio, shown for context. |
| Plot y-axis | −25 to 30 dB SPL | DP-gram amplitude bounds. |
Present, absent, and the noise floor
Present = SNR ≥ criterion and DP ≥ floor. Absent = anything below that. The noise floor is judged separately: high (above the max) means the measurement at that frequency is unusable and cannot count toward a pass, whatever the DP did.
These are the values an organization's settings preset seeds into every new OAE element. The preset holds the criteria and stimulus values only — protocol and tested frequencies are per-case, so they're set in the element, not the preset.
Testing
Each ear gets its own panel (they stack on small screens). A context bar shows the stimulus settings and the present criterion (e.g. SNR ≥ 6 dB).
The learner works frequency by frequency:
- Acquire the measurement (per frequency, or Acquire both ears). The measured DP and noise floor appear on the DP-gram and in the table, the SNR (DP − NF) is computed for them, and the primary tones play (with a faint distortion product where an emission is present).
- Judge the noise floor — OK or High.
- Classify the emission — Present or Absent.
- Record the overall determination for the ear — Pass or Refer.
In practice mode an optional SNR guide can be overlaid on the plot and an answer key revealed. Both are study aids, so in exam mode neither is offered.
Every step is recorded to the attempt's action trail — acquisitions (with the values revealed), each classification, each noise-floor judgement, and the overall call — so an instructor can reconstruct how the learner worked.
Scoring
Scoring is a tri-state per field, per ear — each field is Scored, Report-only (shown on the report, not counted), or Off. The Right and Left ears configure independently, with a Sync Ears toggle to mirror them.
| Field | What's compared |
|---|---|
| Emission (per frequency) | Learner's Present/Absent vs the value derived from the design under the current settings. |
| Noise floor (per frequency) | Learner's OK/High vs whether the design's noise floor clears the max. |
| Overall pass/refer | Learner's decision vs the pass rule (≥ min frequencies to pass present with an acceptable floor, across every tested frequency). |
Comparisons are exact — the SNR and amplitude thresholds are pass/fail rules, so there's no tolerance band. By default all three fields are scored.
Report
After submitting, the results screen carries an OAE breakdown (every scored and report-only field, expected vs submitted) and a View data tab with the DP-gram and a per-frequency comparison.
On the PDF, each configured ear gets its DP-gram — DP markers colored by the derived present/absent call over the shaded noise-floor band — above a table:
| Column | Content |
|---|---|
| Freq | Test frequency (f₂). |
| DP/NF/SNR | The measured values and their signal-to-noise ratio (dB SPL). |
| Expected | The correct read — e.g. Present · NF OK. |
| Submitted | What the learner recorded, or — if they left it blank. |
| Result | ✓ / ✗ for scored fields, — for report-only. |
A final Overall row compares the expected pass/refer against the learner's decision. If the instructor set every field to Off, the element is out of the record entirely and no block is printed.