Tremor type self-test: spiral, straight line, 10 second hold and Hz from a phone video
Weighted Utensils settles one question before you spend money on weight: what kind of shake are you dealing with, and how big is it. You draw two paper tests, hold your arms out for 10 seconds, film three short clips, and write down four numbers. Nothing here names a disease. This test builds the record a clinician can read in two minutes.
What this self-test does, and what it will not do
We built this test because the tremor market sells weight before it sorts the problem. Across the 67 competitor and authority pages we read, not one publishes a home method for telling rest tremor from action tremor from intention tremor. The weight advice arrives first and the triage never arrives at all.
The test produces four records: a spiral and line sheet, a band score, an amplitude figure in millimetres, and an approximate frequency in Hz. It does not diagnose. Diagnosis is a clinician's job, and an occupational therapist works downstream of it: they grade the eating task, measure grip and pinch, and set a written goal.
Read the mechanism first if you have not already. The tremors hub carries the weight bands by tremor type, and the guide index carries the inertia arithmetic and the 14-day trial protocol.
- Rest tremor
- Shakes when the hand is fully supported and still. It often eases the moment you reach, so weight aimed at it may be aimed at nothing.
- Postural tremor
- Appears when a position is held against gravity, such as arms out or a spoon paused mid-air. This is the pattern most often described as responsive to added mass.
- Action tremor
- Appears during movement: scooping, pouring, carrying. Shows up clearly on the spiral and line trace.
- Intention tremor
- Cerebellar pattern that grows in the last centimetres before the target. Extra mass adds inertia, it does not absorb energy, so overshoot can travel further.
- Task-specific tremor
- Present during one task only, for example feeding but not writing. It changes how you design a trial, because your baseline must use the same food every time.
- Dystonic tremor
- Posture and direction specific. If one wrist angle quiets it, a fixed-angle utensil can fight it and an adjustable one may not.
Draw the Archimedes spiral and the straight line corridor
The spiral drawing test is free, it needs one pen, and tremor clinics have used it for decades. Print our template or rule it yourself on plain paper. Do not use lined paper: the lines hide small excursions.
- Tape one sheet of plain paper to the table so it cannot slide under the pen.
- Mark a dot near the top of the sheet. Draw four turns outward from it with even gaps of roughly 5 mm. That is the spiral guide.
- Below it, rule two parallel straight lines 5 mm apart and 12 cm long. That is the corridor.
- Sit with hips and knees at 90 degrees and both feet flat on the floor. equip2adapt.com names the same seating position for feeding setup.
- Hold the pen in your usual grip, lift the forearm clear of the table, and trace the spiral once from the dot outward at a steady speed.
- Trace the corridor once, left to right, without stopping to correct.
- Repeat the whole sheet with the other hand. Write the hand and the date on every sheet.
- Now repeat both sheets with the forearm resting on the table and label these 'supported'. Elbow-on-table stabilisation is free and it often outperforms a purchase.
Keep every sheet. Photograph each one flat, in daylight, with a ruler in frame. Two dated sheets four weeks apart are worth more than any adjective you can offer a clinician.
Score the spiral and line: bands 1 to 5, plus millimetres
Score the trace on how far it leaves the guide, then measure the single widest excursion with a millimetre rule. Amplitude is the number nobody publishes, and it is the one you can measure at home in ten seconds.
| Band | What the trace does | What to write on the sheet |
|---|---|---|
| 1 | Stays inside the 5 mm corridor throughout; spiral gaps stay even | Widest wobble in mm, plus 'no crossings' |
| 2 | Touches a corridor edge once or twice; spiral gaps still even | Number of touches and widest wobble in mm |
| 3 | Crosses the corridor edge repeatedly; spiral gaps vary visibly | Crossings per 12 cm and widest wobble in mm |
| 4 | Leaves the corridor for whole stretches; spiral turns collide | Longest stretch outside the corridor, in cm |
| 5 | Spiral turns overlap or the pen jumps off the paper; the line is unreadable | Write 'unreadable', keep the sheet, stop scoring |
These bands are our own tracking scale for change over time, not a clinical grade. Score the unsupported sheet and the supported sheet separately: the gap between the two is your first real finding.
A writing weight is the cheap analogue of a weighted utensil, and it lets you re-run the spiral under load. SenseAid pen weights add 1.5 oz each with an 8 mm bore and adjustable O-rings, at $14.97 and 4.3 from 595 ratings. Clip one on, trace the spiral again, and compare bands. If mass does nothing on paper, be sceptical that 7 oz of steel will do more at the table.
The 10 second arms-out hold
This one separates postural tremor from rest tremor, and it needs a second person or a propped phone. Ten seconds is long enough for a held-position tremor to build and short enough that fatigue does not confuse the result.
- Sit tall, feet flat, back supported. Rest both hands palms down in your lap and hold still for 10 seconds. Film side-on.
- Raise both arms straight out in front at shoulder height, palms down, fingers spread. Hold for a full 10 seconds. Film again.
- Lower the arms and return the hands to the lap for 10 seconds.
- Repeat the arms-out hold standing, if standing is safe for you and someone is beside you.
- Compare the three clips: lap, arms out seated, arms out standing.
Shake that is absent in the lap and clear with the arms out is a postural pattern. Shake that is present in the lap and quiets when you reach is a rest pattern. Shake that appears only on standing and not seated is the orthostatic pattern, and the practical answer there is a seated meal rather than a purchase.
Write the clip length, the posture and the date in a note beside each video. Untitled phone clips are useless three months later.
Sort it: rest, action or intention
Run this sort with a real spoon and a real bowl, not an empty hand. thenri.org is the only host in our set that publishes when weight stops working, and its cautions apply to two of the three branches below.
Pick Yes or No on each question in turn. Your answers and what they mean collect below the questions, and a Yes gives you the result.
Approximate the frequency in Hz from a phone video
Frequency matters because essential tremor and parkinsonian rest tremor sit in different bands, and mass behaves differently in each. You cannot measure this on paper, but any phone that records 30 frames per second can get you close enough to be worth writing down.
- Prop the phone on a stack of books so the camera itself does not move. Camera shake counts as tremor on playback.
- Frame the hand side-on so it fills most of the frame, with a fixed reference in shot: a table edge, a plate rim or a taped marker.
- Check the video setting and write down the frame rate: 30 fps or 60 fps.
- Record exactly 10 seconds in each posture: hand in lap, arms held out, spoon travelling to the mouth.
- Play the clip back at the slowest speed your phone offers. Count complete back and forth cycles, out and return, for the full 10 seconds.
- Divide the count by 10. That figure is your approximate frequency in Hz.
- Repeat the count once. If your two counts differ by more than about a fifth, film again with better light.
Worked example: you count 45 complete cycles across a 10 second clip, so 45 divided by 10 gives approximately 4.5 Hz. At 30 fps that clip holds 300 frames, which is roughly 6 frames per cycle at that speed: enough to see the turnaround points. A shake near 15 cycles per second would be at the limit of a 30 fps camera, so film at 60 fps if your counts feel like guesses.
Record the Hz figure per posture, not as a single number. Rest, held and moving frequencies can differ, and that difference is exactly what a clinician wants to see.
Rule out the reversible amplifiers before you buy anything
Physiologic tremor gets bigger for reasons that cost nothing to remove. Caffeine, fatigue and some medications all amplify shake. Work this checklist before the test, and note anything you could not remove.
- Caffeine: note how much you drank and how long before the test.
- Sleep and fatigue: record hours slept and whether this is a first-meal or last-meal-of-the-day test.
- Medication: list what you take and when. Ask the prescriber or pharmacist whether anything on it can amplify tremor. Do not stop or change a dose to run a home test.
- Levodopa timing: if you take it, mark whether the test fell in on-time or off-time. The same person may need two different utensils across a three-meal day.
- Elbow support: run the test once with the forearm off the table and once resting on it.
- Table and seat: check table height against seated elbow height, and check the table does not rock.
- Cold hands: a solid steel handle straight from a cold drawer is a different object from a warm one. Warm your hands first.
- Standing versus seated: if the shake only shows standing, sit down to eat before you buy equipment.
What your four numbers change about weight choice
Now match the record to a weight band. Every figure in the middle column below is a published host figure, and every product figure is a recorded price, weight and rating.
| What you recorded | Band the sources cite | Products at that weight |
|---|---|---|
| Shake with arms out only, spiral band 1 to 2 | 4 to 5 oz for light tremor, per one retailer guide | 4.2 oz weighted fork and spoon pair, $22.99, 4.1 from 135 ratings; 3.2 oz built-up teaspoon, $9.99, 4.0 from 143 |
| Shake with arms out and during scooping, band 3 | 6 to 8 oz, per eldershoppe.com, thenri.org and innow.org; approximately one-half pound per michaeljfox.org | Celley 7 oz 4-piece, $34.99, 4.5 from 494; Kinsman KEatlery 7.2 oz 4-piece, $48.26, 4.5 from 369; Vive 7 oz 4-piece, $46.99, 4.5 from 530 |
| Large amplitude, band 4 to 5 | 7 to 8 oz for moderate to severe, per one retailer guide, with the thenri.org caution that extra weight may not steady severe tremor or rigidity | Essential Medical Supply 8 oz 3-piece, $30.94, 4.5 from 266; HandiThings 8 oz worn hand weight, $47.50, 4.0 from 759, with a sizing chart to measure first |
| Worst in the last centimetres before the mouth | No host in our set publishes a weight for intention tremor | Change the plate before the utensil: high-low scoop bowl with suction base, $15.99, 4.1 from 165 |
| Shake mild, and you want the cheapest first change | Built-up handle with no added weight | Special Supplies 5-piece non-weighted set, $16.99, 4.7 from 614; foam grip tubing 9 pcs, $9.99, 8 in long, 1.18 in outer diameter |
The 6 to 8 oz figure repeats across four independent hosts and not one of them cites a study, a sample size or an outcome measure. We treat it as a supplier and clinician convention, not a dose. Bonuci's 6-piece weighted set, $16.99 and 4.0 from 274, states in its own bullets that the product is only suitable for people with mild symptoms and is hand wash only.
Filter the full dataset by weight, mechanism and handedness in reviews, and read how we record and check every spec in about.
What to bring to a clinician
An occupational therapist does not need your interpretation. They need dated evidence and a stated goal. Bring the folder below to the appointment or attach it to the referral.
- All spiral and line sheets, dated, labelled by hand, supported and unsupported.
- Photographs of each sheet with a ruler in frame, plus your widest excursion in millimetres.
- Your band score per sheet, and the difference between the supported and unsupported score.
- The three 10 second videos with the posture and the frame rate written beside each one.
- Your Hz count per posture, and both repeat counts.
- The amplifier checklist with anything you could not remove marked.
- One baseline meal recorded with no device: spill count, meal duration in minutes, and a photograph of the placemat afterwards.
- One sentence naming the goal, for example: eat soup unassisted without changing shirts.
An occupational therapist reads that folder, measures grip and pinch, times a dexterity task such as the Nine Hole Peg Test, checks seating and table height, and matches a handle diameter and weight to what they measure. They also write the letter of medical necessity that funding routes ask for. Re-run this self-test after any new medication, a hospital stay, a fall, unplanned weight loss, a new tremor pattern or any coughing at meals: progressive conditions move the right weight, and a set bought at band 2 rarely still fits at band 4.
Questions people ask
Can this test tell me whether I have essential tremor or Parkinson's?
No. It sorts your shake by posture, measures its size on paper and estimates its frequency. Naming a condition needs a clinical examination and history. What this test does is hand a clinician dated, measured evidence instead of a description.
What is the Archimedes spiral test actually showing?
It shows amplitude and regularity of movement while the hand works against gravity along a curved path. Even spiral gaps and a trace inside the corridor score band 1. Colliding turns and an unreadable line score band 5. It is free, printable and repeatable, which is why tremor clinics keep using it.
How reliable is a Hz figure counted from a phone video?
It is an approximation, not an instrument reading. At 30 fps you have 300 frames across a 10 second clip, which resolves a 4 to 5 cycle per second shake into roughly 6 frames per cycle. Count twice, prop the phone so it cannot move, and film at 60 fps if your two counts disagree.
Why does my shake get worse just before the spoon reaches my mouth?
That end-of-movement pattern is intention tremor, the cerebellar type. Weight adds inertia and does not absorb energy, so a heavier utensil can carry the overshoot further rather then settling it. No source in the 67 pages we read recommends a weight for it, so change the bowl or the setup first and ask an occupational therapist.
Should I test with my elbow on the table or off it?
Both, on separate sheets. Elbow-on-table stabilisation costs nothing and it sometimes improves the trace more than a purchase would. The gap between your supported and unsupported band score tells you how much of the problem is proximal support rather than utensil mass.
My hand only shakes at rest. Will a 7 oz fork help?
Possibly not. Rest tremor often eases once a reaching movement starts, so the shake may already be smaller at the moment you lift food. Test that directly: film the hand in the lap, then film the same hand carrying a loaded spoon, and compare the two clips before you buy.
Is there a cheap way to test whether mass helps before I spend $35 to $48?
Clip a 1.5 oz pen weight from the SenseAid 4-pack, $14.97 and 4.3 from 595 ratings, onto your pen and re-trace the spiral. You can also slide foam grip tubing at $9.99 onto your own fork to test diameter without adding mass. Both cost less than a fifth of a 7 oz steel set.
How often should I repeat the whole self-test?
Re-run it at any of six trigger points: a new medication, a hospital stay, unplanned weight loss, a fall, a new tremor patetrn, or coughing at meals. Otherwise a check every three months is enough to see drift. File the sheets by date so the comparison takes one minute.