Work it out.
Calculators
Pure Tone Average (PTA) and degree of hearing loss
WHO 2021 / ISO 8253
Air-bone gap
Audiologi / ISO 8253
Word Recognition Score
Forholdsregning (taleaudiometri) — klassifikationsskala fra klinisk audiologisk praksis
Standard Threshold Shift (STS) — raw threshold shift
OSHA 29 CFR 1910.95 Appendix F (Standard Threshold Shift — grundformel uden alderskorrektion)
Dynamic range (UCL minus hearing threshold)
Forholdsregning (audiologisk dynamikområde: UCL − høretærskel)
Tympanometry — Jerger classification
Jerger (1970) tympanometri-klassifikation
EEG 10-20 system — electrode distances
International 10-20-system (Jasper 1958 / IFCN-standard)
Nerve conduction velocity (NCV)
Klinisk neurofysiologi — grundformel for nerveledningshastighed
ECG heart rate (square method)
EKG-standard (25/50 mm/s papirhastighed) — "300-metoden" for regelmæssig rytme
QTc — rate-corrected QT interval (Bazett)
Bazett 1920 (QTc = QT / √RR) — fortsat den mest brugte kliniske korrektionsformel
ECG — PR and QRS interval check
Kardiologi.dk referenceværdier for voksen-EKG
ECG — consumables planning (electrodes and paper)
Forholdsregning (forbrugsplanlægning — EKG-drift)
Patient capacity — audiology/neurophysiology
Forholdsregning (klinikplanlægning)
Audiometer — calibration schedule
DS/EN 60645-1 (audiometre) — periodisk kalibreringskontrol; i klinisk praksis typisk mindst årlig
Occupational noise exposure (LEX,8h)
EU-direktiv 2003/10/EF / Arbejdstilsynets støjbekendtgørelse (LEX,8h-normalisering, handlingsværdier 80/85 dB(A))
Masking via air conduction: should masking be applied, and with what
British Society of Audiology recommended procedure: pure-tone audiometry with and without masking (2018)
Hearing aid: gain target according to POGO
POGO (McCandless & Lyregaard, 1983) · POGO II (Schwartz, Lyregaard & Lundh, 1988)
EEG: amplitude and frequency read from the curve
IFCN glossary for clinical EEG (Kane et al. 2017): delta < 4 Hz, theta 4-< 8, alpha 8-13, beta 14-30 Hz
Evoked potentials: number of averages and recording time
Signal averaging: residual noise = noise in one sweep ÷ √N (fundamental principle behind ABR, VEP and SEP)
Tools that work in all subjects
Whatever your programme is called, these tools calculate the same — Pythagoras, area, percentages and units are not tied to one trade.
- Pythagorasa² + b² = c²Find the missing side, set out a right angle, check whether a room is square, and find the space diagonal.
- Area and perimeterm²Rectangle, triangle, trapezium, circle and composite shapes — area and perimeter.
- Volume and surface aream³ · lBox, cylinder, cone, sphere, pyramid, prism, pipe and frustum — also in litres.
- Percent%Percentage of, how many per cent, percentage change, discount and VAT.
- Scale and ratios1 : 50From drawing to reality, area and volume to scale, the rule of three and dividing in a ratio.
- Unit convertermm ↔ mFrom mm to km, Pa to bar and kB to GB — with the unit staircase.
- Time calculations and the clockt : minTime between two clock times, add time, and 1.75 h = 1 h 45 min for the timesheet.
- Slope and fall% · ° · 1:xFall from level to level, in per cent, per mille, degrees and mm per metre — and the height difference.
- Material consumption including wastem² + %Boards, paint, battens at c/c spacing and packs — for a composite surface or a whole room, with waste.